High-throughput calculation method and system for heat conduction characteristic of self-assembled monomolecular layer interface and medium

Abstract

The invention relates to a high-throughput calculation method and system for the heat conduction characteristic of a self-assembled monomolecular layer interface and a medium. The high-throughput calculation method comprises the following steps: introducing a terminal group X structure to perform chain splicing with-S (CH2) n-to construct a monomer chain structure; carrying out charge distribution and force field distribution on the single chain structure; performing high-flux modeling on the monomer chain structure subjected to force field and charge distribution, and constructing a high-flux solid-liquid interface simulation system based on a self-assembled monomolecular layer, a gold substrate and water molecules; sequentially performing NVT simulation, NPT simulation and unbalanced molecular dynamics simulation on the high-flux solid-liquid interface simulation system to obtain heat flux density and a temperature gap; and calculating the interface thermal conductivity of the self-assembled monomolecular layer according to the obtained heat flux density and temperature gap. Compared with the prior art, the method has the advantages that high-throughput calculation of the heat conduction characteristic of the interface of the self-assembled monomolecular layer is realized, and the method is of great significance to development of regulation and control design of the heat conduction characteristic of the interface of the self-assembled monomolecular layer under data driving.

Description

Technical Field

[0001] The present invention belongs to the field of material genetic engineering, and in particular relates to a high-throughput calculation method, system and medium for the interfacial thermal conductivity characteristics of a self-assembled monolayer. Background Art

[0002] Thermal transport across interfaces is crucial for energy transfer and conversion within material systems, such as composite materials, perovskite batteries, nanofluids, thermoelectrics, and thermal phase change materials. However, as the characteristic dimensions of structures approach the nanoscale, the interfacial thermal resistance at the interface between different materials becomes increasingly important, sometimes even dominating.

[0003] Self-assembled monolayer is a mature interface material that can be used to functionalize the surface of materials. Specifically, the formation process of self-assembled monolayer can be understood through the mutual coupling between water entropy, surface tension and free energy. Based on this, the self-assembled monolayer spontaneously forms an interface layer by adsorbing on the surface of the material, thereby achieving the regulation of interfacial thermal resistance. For example, CN111477744A discloses a metal-self-assembled monolayer-organic semiconductor composite structure and preparation method, which uses a sulfur-based monolayer as a medium, and forms a chemical bond with the metal layer and connects to the organic semiconductor layer, so that the interfacial thermal conductivity is significantly improved. The molecular formula of the self-assembled monolayer is HS(CH2) n -R, where n is the carbon chain length of the SAM molecules and R is a polar functional group (alkane, amine, hydroxyl, or carboxyl). The sulfur atoms in the SAM are chemically bonded to the metal layer at the interface. Therefore, structural design of SAMs to manipulate interfacial thermal conductivity is of great significance, thereby improving the interfacial heat transfer efficiency in applications such as micro-nano devices.

[0004] Currently, the application of structural design of self-assembled monolayers in the fields of biosensors, biomedicine, interfacial lubrication and molecular recognition is gradually maturing, but there are still many problems in the research of self-assembled monolayer thermal interface materials. First, the existing experimental and computational data on the interfacial thermal conductivity characteristics of self-assembled monolayers are very limited, resulting in researchers' lack of in-depth understanding of their regulation mechanisms. In addition, existing research mostly focuses on simple components or simple mixed systems of self-assembled monolayers, lacking a systematic analysis of complex multi-chain systems. Secondly, the molecular structure of self-assembled monolayers has millions of potential design candidates. The above shortcomings have resulted in the potential of self-assembled monolayers in interfacial thermal conductivity regulation not being fully explored.

[0005] Therefore, with millions of design candidates for self-assembled monolayer molecular structures, there is an urgent need for a new method that can predict the thermal conductivity properties of the self-assembled monolayer interface to assist researchers in conducting new paradigm research on the thermal conductivity properties of self-assembled monolayers. Summary of the Invention

[0006] The purpose of the present invention is to overcome the current lack of a large-scale automated calculation method for predicting the interfacial thermal conductivity of self-assembled monolayers and to provide a high-throughput calculation method, system, and medium for predicting the interfacial thermal conductivity of self-assembled monolayers. The high-throughput calculation method of the present invention enables theoretical calculation of the interfacial thermal transport properties of self-assembled monolayers with arbitrary structures, assisting researchers in conducting research on complex structures of self-assembled monolayers and providing theoretical support and experimental basis for related applications.

[0007] The purpose of the present invention can be achieved by the following technical solutions:

[0008] The present invention first provides a high-throughput calculation method for the interfacial thermal conductivity characteristics of a self-assembled monolayer, comprising the following steps:

[0009] S1: Introducing terminal X structure and -S(CH2) n - Chain splicing to build monomer chain structure -S(CH2) n -X;

[0010] S2: Charge distribution and force field distribution for the monomer chain structure obtained in S1;

[0011] S3: Perform high-throughput modeling of the self-assembled monolayer based on the monomer chain structure after force field and charge distribution in S2, and construct a high-throughput solid-liquid interface simulation system Au-S(CH2) based on the self-assembled monolayer, gold substrate and water molecules n -X-H2O;

[0012] S4: Perform NVT simulation, NPT simulation, and non-equilibrium molecular dynamics simulation on the high-throughput solid-liquid interface simulation system obtained in S3 in sequence to obtain the heat flux density in the simulation system and the temperature gap obtained by fitting at the interface;

[0013] S5: Calculate the interfacial thermal conductance of the self-assembled monolayer based on the heat flux and temperature gap obtained in S4.

[0014] Furthermore, in step S1, the terminal group X structure is obtained by downloading molecular fragment information from a public database or by self-design.

[0015] Furthermore, in step S1, the terminal group X structure is -S(CH2) n - Use RDKit or STK software to write automated programs to achieve chain splicing.

[0016] Furthermore, in step S2, the force field distribution and charge distribution can be set or configured by using any one of PYSIMM, Material Studio or Amber Tools.

[0017] Furthermore, in step S3, the bond interactions between the sulfur atoms in the self-assembled monolayer and the gold atoms in the gold substrate are simulated using the Morse force field, and the non-bonded interactions between the gold atoms, the self-assembled monolayer molecules, and the water molecules are simulated using the LJ potential.

[0018] Furthermore, in step S3, the high-throughput solid-liquid interface simulation system includes force field information of monomer chain structure, all atomic information of the entire simulation system, bond angle information, and other mixed force field information after high-throughput modeling completes atomic identification.

[0019] Furthermore, the self-assembled monolayer molecules are simulated using PCFF potential, and the water molecules are simulated using TIP3P potential.

[0020] Furthermore, in step S4, the long-range electrostatic interaction of the simulation system is calculated using the PPPM method, and the time step of the simulation system is set to 0.2-0.3 fs.

[0021] Furthermore, in step S4, the temperature in the NVT simulation is set to 300K, and the duration is set to 0.4-0.5 ns.

[0022] Furthermore, in step S4, the temperature in the NPT simulation is set to 300 K, and the duration is set to 0.5-0.7 ns.

[0023] Furthermore, in step S4, the non-equilibrium molecular dynamics simulation adopts an NVE system.

[0024] Furthermore, in step S4, the non-equilibrium molecular dynamics simulation uses a Langevin heat bath as a heat source of 350K and a cold source of 250K, and the duration is 2.0-5.0 ns.

[0025] Furthermore, in step S5, the calculation formula of the interface thermal conductivity is:

[0026] G = q / ΔT;

[0027] Where G is the interface thermal conductivity, q is the heat flux density, and ΔT is the temperature gap at the interface in the direction of heat transport.

[0028] The present invention also provides a high-throughput calculation system for the interfacial thermal conductivity characteristics of a self-assembled monolayer, comprising:

[0029] The high-throughput modeling module is used to construct a high-throughput solid-liquid interface simulation system based on self-assembled monolayers, gold substrates and water molecules; the high-throughput molecular dynamics simulation module is used to perform NVT simulation, NPT simulation and non-equilibrium molecular dynamics simulation on the high-throughput solid-liquid interface simulation system; the high-throughput calculation module is used to calculate the interfacial thermal conductivity characteristics of the self-assembled monolayer based on the simulation results of molecular dynamics simulation.

[0030] The present invention also provides a storage medium containing computer executable instructions, which, when executed by a computer processor, is used to execute the high-throughput calculation method for the interfacial thermal conductivity characteristics of the self-assembled monolayer.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The present invention realizes high-throughput calculation of the interfacial thermal conductivity of self-assembled monolayers based on high-throughput modeling and high-throughput non-equilibrium molecular dynamics simulation. It is of great significance to carry out computationally driven control design of the interfacial thermal conductivity of self-assembled monolayers for millions of design candidate groups of self-assembled monolayer molecular structures.

[0033] (2) The method of the present invention solves the problem of difficulty in obtaining the interfacial thermal conductivity characteristics of self-assembled monolayers with complex end group structures. It can realize the theoretical calculation of the interfacial thermal transport characteristics of self-assembled monolayers with arbitrary structures, assist scientific researchers in conducting research on self-assembled monolayers with complex structures, and provide theoretical support and experimental basis for related applications.

[0034] (3) The method of the present invention unifies the basic settings in the theoretical calculation process of the thermal conductivity characteristics of the interface of self-assembled monolayers, and realizes program automation and lightweight manual intervention in the high-throughput calculation process, which has guiding significance in the prediction of the thermal conductivity characteristics of the interface of self-assembled monolayers in the high-throughput field.

[0035] (4) The high-throughput calculation method of the interfacial thermal conductivity characteristics of the self-assembled monolayer of the present invention has strong applicability. The parameters involved in the calculation process can be changed in accordance with the calculation common sense to obtain the relevant interfacial thermal conductivity characteristics of the self-assembled monolayer, and the high-throughput calculation of the interfacial thermal conductivity characteristics of the self-assembled monolayer can also be achieved.

[0036] (5) The present invention can overcome the theoretical calculation problems such as high preparation and characterization costs and inconsistent calculation processes and force field settings in traditional material research and development methods. It can effectively realize arbitrary modeling of self-assembled monolayers under complex structures and prediction of interfacial thermal conductivity characteristics, realize program automation and lightweight high-throughput operations, save costs and save time. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 Schematic diagram of the high-throughput computing method of the present invention.

[0038] Figure 2 Schematic diagram of the structure of the high-throughput computing system of the present invention.

[0039] Figure 3 Schematic diagram of the high-throughput solid-liquid interface simulation system in Example 2 of the present invention.

[0040] Figure 4 This is a graph showing the relationship between the energy changes at the hot end and the cold end of the self-assembled monolayer with the terminal group -COOH in Example 2 of the present invention and the simulation time.

[0041] Figure 5 This is a cross-sectional view of the temperature distribution of the self-assembled monolayer with terminal groups of -COOH along the heat transport direction in Example 2 of the present invention.

[0042] Figure 6 This is the interface thermal conductivity simulation result of the self-assembled monolayer with terminal groups of -CH3, -OH, and -COOH in Example 2 of the present invention.

[0043] Description of the marks in the figure:

[0044] 1- High-throughput modeling module, 2- High-throughput molecular dynamics simulation module, 3- High-throughput computing module. DETAILED DESCRIPTION

[0045] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention and provides a detailed implementation method and specific operating process. However, the scope of protection of the present invention is not limited to the following embodiment. Features such as component models, material names, connection structures, control methods, algorithms, etc. that are not clearly described in this technical solution are considered common technical features disclosed in the prior art.

[0046] The present invention aims to address the current lack of a high-throughput computational method for predicting the interfacial thermal conductivity of self-assembled monolayers (SAMs). This method enables theoretical calculation of the interfacial thermal transport properties of SAMs under arbitrary structures, assisting researchers in studying SAMs with complex structures. This method uses nonequilibrium molecular dynamics simulations to determine the interfacial thermal conductivity of SAMs, primarily involving high-throughput modeling and high-throughput nonequilibrium molecular dynamics simulations.

[0047] Specifically, the first aspect of the present invention provides a high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer, such as Figure 1 As shown, the specific steps include:

[0048] S1: Introducing terminal X structure and -S(CH2)n - Chain splicing to build monomer chain structure -S(CH2) n -X;

[0049] S2: Charge distribution and force field distribution for the monomer chain structure obtained in S1;

[0050] S3: Perform high-throughput modeling of the self-assembled monolayer based on the monomer chain structure after force field and charge distribution in S2, and construct a high-throughput solid-liquid interface simulation system Au-S(CH2) based on the self-assembled monolayer, gold substrate and water molecules n -X-H2O;

[0051] S4: Perform NVT simulation, NPT simulation, and non-equilibrium molecular dynamics simulation on the high-throughput solid-liquid interface simulation system obtained in S3 in sequence to obtain the heat flux density in the simulation system and the temperature gap obtained by fitting at the interface;

[0052] S5: Calculate the interfacial thermal conductance of the self-assembled monolayer based on the heat flux and temperature gap obtained in S4.

[0053] In some specific embodiments, in step S1, the terminal group X structure is obtained by downloading molecular fragment information from a public database or by self-design.

[0054] In some specific embodiments, the terminal group X structure is -S(CH2) n - Use RDKit or STK software to write automated programs to achieve chain splicing.

[0055] In some specific embodiments, in step S2, the force field distribution and charge distribution can be set or configured by using any one of PYSIMM, Material Studio or Amber Tools.

[0056] In some specific embodiments, in step S3, the bond interactions between the sulfur atoms in the self-assembled monolayer and the gold atoms in the gold substrate are simulated using the Morse force field, and the non-bonded interactions between the gold atoms, the self-assembled monolayer molecules, and the water molecules are simulated using the LJ potential.

[0057] In some specific embodiments, in step S3, the high-throughput solid-liquid interface simulation system includes force field information of monomer chain structure, all atomic information of the entire simulation system, bond angle information, and other mixed force field information after high-throughput modeling completes atomic identification.

[0058] In some specific embodiments, in step S3, the self-assembled monolayer molecules are simulated using PCFF potential, and the water molecules are simulated using TIP3P potential.

[0059] In some specific embodiments, in step S4, the long-range electrostatic interaction of the simulation system is calculated using the PPPM method, and the time step of the simulation system is set to 0.2-0.3 fs.

[0060] In some specific embodiments, in step S4, the temperature in the NVT simulation is set to 300K, and the duration is set to 0.4-0.5ns.

[0061] In some specific embodiments, in step S4, the temperature in the NPT simulation is set to 300K, and the duration is set to 0.5-0.7 ns.

[0062] In some specific embodiments, in step S4, the non-equilibrium molecular dynamics simulation uses an NVE system, a Langevin thermal bath as a heat source of 350K and a cold source of 250K, and the duration is 2.0-5.0 ns.

[0063] In some specific embodiments, in step S5, the calculation formula of the interface thermal conductivity is:

[0064] G = q / ΔT;

[0065] Where G is the interface thermal conductivity, q is the heat flux density, and ΔT is the temperature gap at the interface in the direction of heat transport.

[0066] The second aspect of the present invention provides a high-throughput calculation system for the thermal conductivity characteristics of the interface of a self-assembled monolayer, such as Figure 2 As shown, the system specifically includes: a high-throughput modeling module 1, which is used to construct a high-throughput solid-liquid interface simulation system based on a self-assembled monolayer, a gold substrate and water molecules; a high-throughput molecular dynamics simulation module 2, which is used to perform NVT simulation, NPT simulation and non-equilibrium molecular dynamics simulation on the high-throughput solid-liquid interface simulation system; and a high-throughput calculation module 3, which is used to calculate the interfacial thermal conductivity characteristics of the self-assembled monolayer based on the simulation results of the molecular dynamics simulation.

[0067] A third aspect of the present invention provides a storage medium comprising computer-executable instructions, which, when executed by a computer processor, is used to perform the above-mentioned high-throughput calculation method for the interfacial thermal conductivity characteristics of self-assembled monolayers.

[0068] The storage medium of the present invention can be an electronic medium, a magnetic medium, an optical medium, an electromagnetic medium, an infrared medium, or a semiconductor system or a propagation medium. The storage medium can also include a semiconductor or solid-state memory, a magnetic tape, a removable computer disk, a random access memory (RAM), a read-only memory (ROM), a hard disk, and an optical disk. Optical disks can include compact disk-read only memory (CD-ROM), compact disk-read-write (CD-RW), and DVD.

[0069] The above embodiments can be implemented individually or in any combination of two or more. The above embodiments will be described in more detail below with reference to specific examples.

[0070] Example 1:

[0071] This embodiment provides a high-throughput calculation method for predicting the interfacial thermal conductivity characteristics of self-assembled monolayers, which mainly includes two steps: high-throughput modeling and high-throughput non-equilibrium molecular dynamics simulation.

[0072] (1) The single-chain carrier of the self-assembled monolayer in high-throughput modeling is generally HS(CH2) n -X, that is, the single-layer chain consists of three parts: the head group -S-, the chain -(CH2) n - and terminal group X. The head group is attached to the gold substrate surface, and the sulfur atom easily forms a strong bond with the gold atom, similar to a covalent bond. The structure of the terminal group X attached to the -CH2- end can be freely designed. The structure of the terminal group X can be obtained from a database or designed by the researcher.

[0073] Specifically, the self-assembled monolayer constructed in this example is arranged in an 8×8 array on the surface of a gold (111) substrate with a face-centered cubic lattice structure. Each side of the substrate is composed of 25 layers of gold atoms, and 64 single chains of the self-assembled monolayer are distributed at the interface, with the distance between sulfur atoms being 0.497 nanometers. In addition, 2000 water molecules are compacted in the space between the gold substrate and the self-assembled monolayer at the solid-liquid interface.

[0074] (2) For high-throughput non-equilibrium molecular dynamics simulation, non-equilibrium molecular dynamics simulation is closer to the experimental process of heat transport measurement. By applying a fixed temperature controller (heat source and heat sink) to the material heat transport system, heat flow and temperature gradient can be generated inside the material, thereby directly solving the interface thermal conductivity G. When the system reaches a stable state, the interface thermal conductivity can be calculated:

[0075] G=q / ΔT (1)

[0076] Where q is the heat flux density and ΔT is the temperature gradient at the interface in the direction of heat transport.

[0077] A hybrid force field distribution was used in the molecular dynamics simulation, in which the Morse force field was used to simulate the bond interactions between sulfur atoms in the sulfur-based self-assembled layer and gold atoms in the gold substrate. The specific formula is:

[0078]

[0079] Where D0 is the bond dissociation energy, r0 is the equilibrium bond length, and α is the atomic characteristic parameter. This type of force field has been successfully used in the simulation of gold-self-assembled monolayer structures. The cutoff radius r of the Morse force field in the calculation is c Set to r <r c .

[0080] In the calculation of thermal transport properties at the solid-liquid interface, the TIP3P potential is used for water molecules, which can well reproduce the thermodynamic and structural properties of water. The PCFF potential is used for self-assembled monolayer molecules.

[0081] In addition, the non-bonded interactions between gold atoms, self-assembled monolayer molecules, and water molecules are simulated using the LJ potential, and the calculation formula is:

[0082]

[0083] Among them, ε and σ represent energy and length scale respectively, r ij is the distance between atoms i and j. Except for the sulfur atom covalently bonded to the gold atom, the parameters of the LJ potential are set to the modified universal force field (UFF), and the cutoff r of the LJ potential is c The radius is set to r <r c .

[0084] The long-range electrostatic interactions of the entire system were calculated using the PPPM method with an accuracy of 1×10 -5 Considering the presence of relatively light hydrogen atoms in the system, a time step of 0.25 fs was chosen. All simulation input files were prepared by an automated system and connected to the LAMMPS software for molecular dynamics simulations.

[0085] During the simulation, the system was first equilibrated in the canonical ensemble (NVT) at 300 K for 0.5 ns. The system was then optimized in the isothermal-isobaric ensemble (NPT) at 300 K for 0.6 ns. Finally, a nonequilibrium molecular dynamics simulation was performed in the microcanonical ensemble (NVE) for 2 ns, with a Langevin heat bath as the heat source at 350 K and the cooler at 250 K. Once the nonequilibrium state stabilized, the interfacial thermal conductance was obtained by periodically acquiring the heat flux in the simulated system and the fitted temperature gap at the interface.

[0086] Specifically, the high-throughput calculation method of this embodiment specifically adopts the following steps:

[0087] S1: Loading of the terminal group X structure. You can download molecular fragment information as X from the public database, or design the terminal group X structure yourself;

[0088] S2: terminal X structure and -S(CH2) n -Connection, creating a monomer chain structure of self-assembled single molecules;

[0089] S3: Use PYSIMM to assign relevant charges to the monomer chain structure and assign force fields to the PCFF potential;

[0090] S4: Use the ITC-SAM program to perform high-throughput modeling of the monomer chain structure after force field and charge distribution, and realize the construction of a high-throughput non-equilibrium molecular dynamics simulation system;

[0091] S5: Write the input file through the ITC-SAM program, automatically connect to the LAMMPS software, and perform canonical ensemble (NVT) simulations;

[0092] S6: The ITC-SAM program is used to combine the canonical ensemble (NVT) simulation results into an input file, which is automatically connected to the LAMMPS software to perform isothermal-isobaric ensemble (NPT) simulations.

[0093] S7: The ITC-SAM program is used to combine the isothermal-isobaric ensemble (NPT) simulation results into an input file, which is automatically connected to the LAMMPS software to perform non-equilibrium molecular dynamics simulations.

[0094] S8: The ITC-SAM program is combined with the non-equilibrium molecular dynamics simulation results to automatically obtain the heat flux density in the simulation system and the temperature gap obtained by fitting at the interface, and the interface thermal conductivity is obtained. The calculation formula is as follows (1).

[0095] Furthermore, in step S2, an automated program can be written using software such as RDKit and STK to achieve simple chain splicing.

[0096] Furthermore, the monomer chain structure in step S3 can be automatically assigned to the force field and charge using tools such as PYSIMM. Alternatively, the force field can be assigned by writing reliable force field parameters.

[0097] Furthermore, the modeling file in step S4 mainly includes a data file suitable for LAMMPS reading after automated modeling using the ITC-SAM program, which contains the force field information of the monomer chain structure and all atomic information of the entire simulation system; it also includes other mixed force field files after the ITC-SAM program completes atom identification, in which the Morse force field is used to simulate the bond interaction between the sulfur atoms in the sulfur-based self-assembled layer and the gold atoms in the gold substrate, as shown in formula (2); in addition, if the thermal transport properties of the solid-liquid interface are calculated, the TIP3P potential is used for water molecules; the LJ potential is used to simulate the non-bonded interaction between gold atoms, self-assembled monolayer molecules, and water molecules, as shown in formula (3). Here, except for the sulfur atoms covalently bound to the gold atoms, the parameters of the LJ potential are set using the modified universal force field (UFF).

[0098] Furthermore, in step S5, the system is equilibrated in a canonical ensemble (NVT) at a temperature of 300 K for 0.5 nanoseconds, and the long-range electrostatic interactions of the entire system are calculated using the PPPM method with an accuracy of 1×10 -5 Considering the presence of lighter hydrogen atoms in the system, 0.25fs is selected as the system time step; the cutoff radius of the Morse force field in the calculation is set to The cutoff radius of the LJ potential is set to

[0099] Furthermore, in step S6, the system is optimized in an isothermal-isobaric ensemble (NPT) with a temperature of 300 K and a time of 0.6 ns; other calculation settings are consistent with those in step S5.

[0100] Furthermore, in step S6, the system performs non-equilibrium molecular dynamics simulation in a microcanonical ensemble (NVE), wherein a Langevin heat bath is used as a heat source at a constant temperature of 350K and a cold source at a constant temperature of 250K, with a duration of 2ns, and other calculation settings are consistent with step S5.

[0101] The above method has strong applicability. The calculation settings involved in the calculation process, such as time step, running time, truncation radius, force field parameters, etc., can be changed in accordance with common sense to obtain the relevant self-assembled monolayer interface thermal conductivity characteristics. That is, when carrying out relevant calculations according to the method of the present invention, even if the relevant calculation settings are changed, high-throughput calculations can still be achieved.

[0102] Example 2:

[0103] This example provides a high-throughput computational method for predicting the interfacial thermal conductivity of self-assembled monolayers. This method constructs multiple sets of self-assembled monolayer models to calculate interfacial thermal conductivity. The method primarily includes the following steps:

[0104] S1: loading of terminal -CH3, -OH, -COOH structures;

[0105] S2: terminal group -CH3, -OH, -COOH structure and -S(CH2) n -connection, creating a self-assembled single-molecule monomer chain structure with equal number of carbon atoms, i.e., -S(CH2)5-CH3, -S(CH2)6-OH, -S(CH2)5-COOH;

[0106] S3: Perform relevant charge distribution and PCFF potential force field distribution on the monomer chain structures -S(CH2)5-CH3, -S(CH2)6-OH, and -S(CH2)5-COOH;

[0107] S4: The monomer chain structures -S(CH2)5-CH3, -S(CH2)6-OH, and -S(CH2)5-COOH after force field and charge distribution are modeled in high throughput through the ITC-SAM program to achieve the construction of a high-throughput non-equilibrium molecular dynamics simulation system. The example here uses a solid-liquid interface system, namely Au-S(CH2)5-CH3-H2O, Au-S(CH2)6-OH-H2O, and Au-S(CH2)5-COOH-H2O.

[0108] The modeling file mainly includes the data file suitable for LAMMPS reading after the automatic modeling by the ITC-SAM program, which contains the force field information of the monomer chain structure and all the atomic information of the entire simulation system. It also contains other mixed force field files after the atomic identification by the ITC-SAM program. Among them, the Morse force field is used to simulate the bond interaction between the sulfur atoms in the sulfur-based self-assembled layer and the gold atoms in the gold substrate, as shown in formula (2). In addition, in the calculation of the thermal transport properties of the solid-liquid interface, the TIP3P potential is used for water molecules; the non-bonded interactions between gold atoms, self-assembled monolayer molecules, and water molecules are simulated using the LJ potential. Here, except for the sulfur atoms covalently bound to the gold atoms, the parameters of the LJ potential are set to the modified universal force field (UFF).

[0109] Among them, the high-throughput solid-liquid interface system is shown in the figure below. Figure 3 As shown in Figure 2, the self-assembled monolayers are arranged in an 8×8 array on a gold (111) substrate with a face-centered cubic lattice structure. Each side of the substrate consists of 25 layers of gold atoms, and 64 single chains of the self-assembled monolayer are distributed at the interface, with the distance between sulfur atoms being 0.497 nanometers. In addition, 2000 water molecules are compacted in the space between the gold substrate and the self-assembled monolayer at the solid-liquid interface.

[0110] S5: Input files were written using the ITC-SAM program and automatically connected to the LAMMPS software to perform canonical ensemble (NVT) simulations. The system was equilibrated in the NVT ensemble at 300 K for 0.5 nanoseconds. The long-range electrostatic interactions of the entire system were calculated using the PPPM method with an accuracy of 1×10 -5 Considering the presence of lighter hydrogen atoms in the system, 0.25fs is selected as the system time step; the cutoff radius of the Morse force field in the calculation is set to The cutoff radius of the LJ potential is set to

[0111] S6: The ITC-SAM program is used to write the input file in combination with the canonical ensemble (NVT) simulation results, and the LAMMPS software is automatically connected to perform an isothermal-isobaric ensemble (NPT) simulation. The system is optimized in the isothermal-isobaric ensemble (NPT) with a temperature of 300 K and a time of 0.6 nanoseconds. Other calculation settings are consistent with the example step S5.

[0112] S7: The input file is written by combining the isothermal-isobaric ensemble (NPT) simulation results with the ITC-SAM program, and the LAMMPS software is automatically connected to carry out non-equilibrium molecular dynamics simulations; the system carries out non-equilibrium molecular dynamics simulations in the microcanonical ensemble (NVE), wherein the Langevin bath is used as a heat source at a constant temperature of 350K and a cold source at a constant temperature of 250K, and the duration is 2 nanoseconds; the other calculation settings are consistent with the step S5. The relationship between the energy change of the hot end and the cold end of the self-assembled monolayer with the terminal group -COOH in the Langevin bath and the simulation time under the high-throughput calculation method of the present invention is as follows Figure 4 As shown in the figure, during the entire non-equilibrium molecular dynamics simulation process, the energy input and output of the heat source and heat sink of the simulation system have the same trend over time (positive and negative only represent input and output), indicating that the simulation system is in a stable state during the process of obtaining the interface thermal conductivity G by this method.

[0113] S8: The heat flux density in the simulation system is automatically obtained by combining the ITC-SAM program with the results of non-equilibrium molecular dynamics simulation. Taking the interface thermal conductivity calculation of the self-assembled monolayer of -COOH as an example, its heat flux density q (4623.47MW / m 2 ) is directly simulated by the mean energy E (643.1eV) of the heat source and heat sink parts, and the cross-sectional area S of the system along the heat flow direction is directly simulated by the mean energy E (643.1eV) of the heat source and heat sink parts. The product of the simulation running time (1.6ns) is divided by the unit conversion to obtain the temperature gap obtained by fitting at the interface. Taking the interface thermal conductivity calculation of the self-assembled monolayer of -COOH as an example, the cross-sectional diagram of the temperature distribution of the self-assembled monolayer with the terminal group -COOH along the heat transport direction under the high-throughput calculation method of the present invention is as follows: Figure 5 As shown. ΔT1 and ΔT2 are 26.861K and 27.421K respectively, and their average ΔT is 27.141K. Finally, the heat flux density q is divided by the temperature gap ΔT to obtain the interface thermal conductivity G. The interface thermal conductivity simulation results of the self-assembled monolayer with terminal groups of -CH3, -OH, and -COOH under the high-throughput calculation method of the present invention are shown as follows: Figure 6 As shown, the interface thermal conductivity G calculated by repeated simulation is 45.9~48.2MW / m 2 K, 141.0~152.5MW / m 2 K, 159.7~170.3MW / m 2 K. In addition, this high-throughput calculation method was also compared with the results of a previously published paper (HUANG DZ, MAR M, ZHANG T, et al. Origin of hydrophilic surface functionalization-induced thermal conductance enhancement across solid-water interfaces [J]. Acs Appl Mater Inter, 2018, 10 (33): 28 159-28 165.). Figure 6 As shown, the accuracy and reliability of this high-throughput calculation method are demonstrated.

[0114] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, the present invention is not limited to the above-described embodiments. Improvements and modifications made by those skilled in the art based on the disclosure of the present invention, without departing from the scope of the present invention, should be within the scope of protection of the present invention.

Claims

1. A high-throughput calculation method for the interfacial thermal conductivity of self-assembled monolayers, characterized in that: The following steps are involved: S1: Introducing terminal X structure and -S(CH2) n - Chain splicing to build monomer chain structure -S(CH2) n -X; S2: Charge distribution and force field distribution for the monomer chain structure obtained in S1; S3: Perform high-throughput modeling of the self-assembled monolayer based on the monomer chain structure after force field and charge distribution in S2, and construct a high-throughput solid-liquid interface simulation system Au-S(CH2) based on the self-assembled monolayer, gold substrate and water molecules n -X-H2O; S4: Perform NVT simulation, NPT simulation, and non-equilibrium molecular dynamics simulation on the high-throughput solid-liquid interface simulation system obtained in S3 in sequence to obtain the heat flux density in the simulation system and the temperature gap obtained by fitting at the interface; S5: Calculate the interfacial thermal conductance of the self-assembled monolayer based on the heat flux and temperature gap obtained in S4.

2. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S1, the terminal group X structure is obtained by downloading molecular fragment information from a public database or by self-design; The terminal group X structure is -S(CH2) n - Use RDKit or STK software to write automated programs to achieve chain splicing.

3. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S2, the force field distribution and charge distribution are set up or configured by oneself using any one of PYSIMM, Material Studio or Amber Tools.

4. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S3, the bond interactions between the sulfur atoms in the self-assembled monolayer and the gold atoms in the gold substrate are simulated using the Morse force field, and the non-bonded interactions between the gold atoms, the self-assembled monolayer molecules, and the water molecules are simulated using the LJ potential.

5. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S3, the high-throughput solid-liquid interface simulation system includes force field information of monomer chain structure, all atomic information of the entire simulation system, bond angle information, and other mixed force field information after high-throughput modeling completes atom identification; The self-assembled monolayer molecules were simulated using PCFF potential, and the water molecules were simulated using TIP3P potential.

6. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S4, the long-range electrostatic interaction of the simulation system is calculated using the PPPM method, and the time step of the simulation system is set to 0.2-0.3 fs; The temperature in the NVT simulation was set to 300 K and the duration was set to 0.4–0.5 ns; The temperature in the NPT simulation was set to 300 K and the duration was set to 0.5-0.7 ns.

7. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S4, the non-equilibrium molecular dynamics simulation adopts the NVE system; In the non-equilibrium molecular dynamics simulation, a Langevin heat bath was used as a heat source at 350 K and a cold source at 250 K, with a duration of 2.0-5.0 ns.

8. The high-throughput calculation method for the interfacial thermal conductivity of a self-assembled monolayer according to claim 1, characterized in that: In step S5, the calculation formula of the interface thermal conductivity is: G = q / ΔT; Where G is the interface thermal conductivity, q is the heat flux density, and ΔT is the temperature gap at the interface in the direction of heat transport.

9. A high-throughput calculation system for the thermal conductivity characteristics of the interface of self-assembled monolayers, characterized in that: include: High-throughput modeling module, used to construct a high-throughput solid-liquid interface simulation system based on self-assembled monolayers, gold substrates, and water molecules; High-throughput molecular dynamics simulation module, used to perform NVT simulation, NPT simulation and non-equilibrium molecular dynamics simulation on high-throughput solid-liquid interface simulation system; A high-throughput computational module for calculating the interfacial thermal conductivity of self-assembled monolayers based on molecular dynamics simulation results.

10. A storage medium containing computer-executable instructions, characterized in that: When the computer-executable instruction storage medium is executed by a computer processor, it is used to perform the high-throughput calculation method of the interfacial thermal conductivity characteristics of the self-assembled monolayer according to any one of claims 1 to 8.

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