100 results about "Hot electrons" patented technology

The invention provides application of a silver-bismuth tungstate catalyst in preparation of methanol from light-driven CO2, and belongs to the technical field of CO2 conversion and reduction. Bismuth tungstate nanosheets, silver salt and water are mixed, the size of silver particles is controlled by adjusting the pH value, the silver-bismuth tungstate catalyst is obtained, and the size of the silver particles is 20-50 nm; silver is evenly distributed on the surface of bismuth tungstate, the obtained silver-bismuth tungstate catalyst is large in specific surface area and high in light response capacity, the silver-bismuth tungstate catalyst can generate a large number of high-energy hot electrons during illumination, in-situ photo-thermal conversion is achieved, no external heat source is needed for heat supply, the photo-thermal effect is enhanced, CO2 conversion is promoted, and the methanol yield is increased.

An integrated configurable photodetector with an ultra-high circular polarization extinction ratio and a preparation method therefor are provided. The photodetector includes a metal reflective layer, a dielectric layer, an electrode layer, and a two-dimensional material layer. The electrode layer includes symmetrically arranged Z-shaped metallic optical antenna arrays which are respectively integrated with a source electrode and a drain electrode and have opposite chirality. The photodetector operates at zero bias state, and a photo-response is photovoltaic effect, hot electron injection, photo-thermoelectric effect and so on induced by a Schottky junction composed of the source electrode, the drain electrode and the two-dimensional material. By adjusting the distribution of the incident light in the source and drain electrode regions, under specific Circularly polarized light, photocurrents of equal magnitude but opposite directions cancel each other out, resulting in a net output of zero and significantly reducing noise.

The invention discloses an ion etching device for PVD (Physical Vapor Deposition) coating equipment. The ion etching device comprises an auxiliary anode, a main and standby double-group tungsten filament heating module, an inert gas directional introduction module, a vacuum and electric connection module and a control and protection module. Through the design of the main and standby tungsten filaments and the automatic overlapping switching strategy, it is ensured that when one tungsten filament fails, seamless switching to the standby tungsten filament can be achieved, shutdown caused by filament breakage or degradation is effectively avoided, the service life of the device is prolonged, long-period continuous production is guaranteed, and the operation efficiency and production continuity of the device are greatly improved. Meanwhile, electric arc particle pollution is avoided through hot electron emission, and the surface cleanliness is high; the matching range of pressure, bias pressure and gas is wide, the method is suitable for multiple materials and complex morphology, and the process repeatability is good; the flange and the electric penetration assembly are modularized, and the tungsten filament / anode / gas supply assembly is quickly replaced, so that the maintenance time is shortened, and the maintenance cost is reduced; the whole system is simple in structure, does not need a complex magnetic field and a multi-stage electrode, and is low in equipment manufacturing cost.

The present invention provides a gallium nitride-based light-emitting diode epitaxial structure, a preparation method thereof, and an LED chip. In the epitaxial structure, a multi-level electron-phonon scattering structure, a stepwise increase in the bandgap width of the quantum well layer in the multi-quantum well barrier layer, and an InGaN step structure are designed to suppress electron leakage in different situations, targeting electron ballistic transport, electron acceleration caused by the quantum Stark effect structure in the quantum well, and hot electron transition. This effectively improves the external quantum efficiency under high current.

The invention discloses a construction method of a graphene near-infrared detector with a GaAs substrate and the detector. Silvaco Tcad and Lumeral FDTD are used for constructing an equivalent structure model of the optical detector, and the optical performance and the electrical performance of the optical detector are analyzed; an optical detector equivalent structure model comprises a p-type graphene heterojunction and an n-type GaAs substrate, the graphene heterojunction is formed by stacking graphene, InSb and AlSb, and the thickness and doping concentration of each layer of the graphene heterojunction are accurately controlled to form a unique graphene heterojunction, so that the pn-type photoelectric detector with excellent optical response performance is constructed. According to the detector, generation of photon-generated carriers can be accelerated under the action of a built-in electric field, recombination is reduced, and the light responsivity of the detector is improved; meanwhile, hot electrons excited in the InSb dielectric layer can cross an interface barrier to be injected into the graphene, and rapid response is achieved through ballistic transport of the graphene.

The application relates to the technical field of photoelectric detection, and discloses an infrared detector and a preparation method thereof. The infrared detector comprises a substrate, a metal sensitive film, a light absorption enhancement structure and a current transmission structure. The light absorption enhancement structure comprises a Schottky junction. The Schottky junction is formed by etching an arrayed pattern on a silicon substrate, the arrayed pattern is filled with metal, the silicon substrate is in contact with the metal to form the Schottky junction, and the Schottky interface is subjected to roughening treatment to enhance hot electron absorption. The current transmission structure comprises a silicon substrate, a P-type conductive structure, an N-type conductive structure and a dielectric material. The current generated by the light absorption enhancement structure is led out from the P-type and N-type conductive structures. The Schottky interface is subjected to roughening treatment to enhance hot electron absorption, a back-illumination method is adopted, and the free path of hot electron transmission is shortened, so that the quantum efficiency of the detector is improved.

This invention discloses a copper-tungsten oxide / zinc oxide heterojunction photocatalyst, its preparation method, and its application, belonging to the field of nanomaterials and photocatalysis technology. Firstly, a single-atom copper-modified plasma W-type photocatalyst is synthesized using a solution-thermal method combined with an impregnation-thermal reduction process. 18 O 49 Nanowires were first prepared; then porous ZnO nanosheets were prepared via a hydrothermal method combined with calcination; finally, single-atom copper-modified plasma W was constructed via electrostatic self-assembly. 18 O 49 Nanowire / porous ZnO nanosheet heterojunction composite material. This invention utilizes the above-described preparation method to prepare Cu-W nanowires with matched band structures. 18 O 49 / ZnO heterojunction can realize the photogenerated electrons of ZnO into the plasma Cu-W 18 O 49 Nanowire implantation stabilizes and increases the surface oxygen vacancy concentration and free electron density, thereby enhancing the surface plasmon resonance effect and promoting the continuous generation of high-energy hot electrons. Single-atom copper active sites and W 18 O 49 The synergistic effect of nanowires enables the enriched hot carriers to efficiently and selectively photocatalytically reduce CO2 to CH4.

The application discloses a method for realizing ionosphere aircraft stealth based on regulating and controlling electron distribution of tail area, first, evolution time scales under different non-extended parameters are calculated; and according to the superhot electron energy and particle flux per unit time required by different non-extended parameters, a radio frequency discharge plasma generator is controlled to generate plasma corresponding to the non-extended parameters; then, in the grid electric field, electrons enter the acceleration field area, and ions are directly discharged to the tail area of the aircraft without acceleration; the regulation and control duration under different non-extended parameters is determined by the evolution time scale corresponding to the non-extended parameter. The application changes the electron distribution of the ionosphere aircraft tail area by randomly injecting high-energy electrons into the tail area of the aircraft, regulates and controls the evolution law and characteristic scale of the non-linear local cavity in the tail area which cannot be eliminated, makes the anti-stealth method of monitoring the motion of the density cavity to detect the ionosphere stealth aircraft invalid, and thus realizes the stealth of the ionosphere stealth aircraft.

The invention discloses a vacuum measuring tool and a vacuum degree measuring method, and the vacuum measuring tool comprises a measuring circuit which comprises a power supply which is a constant-voltage constant-frequency AC power supply; a resistive element; the current detection element is connected in series with the resistance element and is used for acquiring a current measurement value of the measurement circuit; the capacitor assembly is connected with the resistor element in series; a medium space between polar plates of the capacitor assembly is used for being communicated with a to-be-measured space, a current measurement value collected by the current detection element is in positive correlation with a capacitance value of the capacitor assembly, and the capacitance value of the capacitor assembly is in positive correlation with the vacuum degree of the to-be-measured space. According to the invention, the capacitor assembly is adopted to form the measurement circuit, the conversion from the collected current measurement value to the vacuum degree is realized, the device can be suitable for the measurement in different vacuum states, the precision is high, the integration degree is high, the space is saved, and the system complexity and the maintenance cost are reduced; and the technical barrier that a hot cathode vacuum gauge receives hot electrons is effectively avoided, and the problem that a high-vacuum measuring tool is short in service life is fundamentally solved.

The invention relates to the technical field of solar cells, and particularly discloses a crystalline silicon thermal electron solar cell and a photovoltaic module, which comprise a silicon substrate, and the silicon substrate comprises a P-type region and an n-type region positioned on one side of an illumination surface of the P-type region; the illumination surface of the silicon substrate is provided with a silver collection gate electrode, and the back side of the silicon substrate is provided with a silver extraction electrode; an Ag-Si semiconductor alloy junction is arranged at the position, corresponding to the silver collection gate electrode, in the silicon substrate, an n-type ultra-shallow diffusion layer is formed on the outer side of the Ag-Si semiconductor alloy junction, an n-P junction is formed between the n-type ultra-shallow diffusion layer and the P-type region, and the n-P junction and the n-P junction form a three-dimensional PN junction quantum well; the silver collection gate electrode and the Ag-Si semiconductor alloy structure form a contact electrode. Thermo-electron transmission is accelerated, thermo-electron extraction and utilization are realized, and the photoelectric conversion efficiency is further improved.

The present invention relates to a method for regulating hot electron transport in a metal heterostructure through controllable electroacoustic coupling, and belongs to the technical field of hot electron transport dynamics in nanomaterials. The method comprises: preparing a metal heterostructure; utilizing transient reflectance spectroscopy and extracting peak signal dynamics; simulating through a two-temperature equation and fitting the electroacoustic coupling coefficient G as a variable, iteratively obtaining the G value and quantifying the interface thermal conductivity; obtaining the spatial distribution of hot electrons with different time delays through ultrafast microscopy, and determining the hot electron spatiotemporal distribution evolution curve through two-dimensional Gaussian function fitting; adopting a two-component diffusion model fitting to quantitatively describe the hot electron diffusion behavior; comparing the fitting results with the G value to understand the effect of regulating the electroacoustic coupling on the hot electron diffusion. The present invention controls the electroacoustic coupling strength by regulating the physical properties of the buried layer metal, analyzes the relationship between G and hot electron transport, and provides new insights into improving hot electron transport and optimizing the performance of optoelectronic devices based on hot carriers.

The application provides an ion source upper cover assembly and an ion source device. The fixed shielding cage in the ion source upper cover assembly can prevent the annular filament from being directly in contact with external structures to cause deformation or damage. The structure of the annular filament can effectively push the hot electrons emitted by the annular filament towards the ionization chamber, improve the ionization effect, and the ion source device is provided with the annular filament. The annular filament, the ionization cylinder and the shielding cage are coaxial, so that the electrons emitted by the annular filament can move in a more uniform electric field, thereby improving the probability of electron bombardment on the sample gas and improving the ionization efficiency and stability of the ion source device. Meanwhile, the ion source device has a wide range of emission current dynamic interval, strong anti-interference ability and wide range of sensitivity linear plateau area. The total pressure focusing electrode structure in the ion source device can also monitor the vacuum value in the detected space in real time, thereby playing a role in protecting the filament and the vacuum system.

To provide a leak detector and an ion source for a leak detector that improve the insulation durability between electrodes without changing the size and weight of the ion source. A leak detector that guides a gas from an object to be inspected to an analysis tube that is evacuated, ionizes the gas using an ion source provided in the analysis tube, and detects the ionized gas to thereby perform a leak inspection on the object to be inspected, wherein the ion source includes a filament that emits hot electrons that ionize the gas, an electrode that is electrically connected to the filament, a base member through which the electrode passes and that separates an internal space in which the filament is disposed from the outside, a first insulation member that is provided in a through-hole for the electrode formed in the base member and that insulates the electrode from the base member, and a second insulation member that is provided around the electrode and that extends toward the internal space side more than a surface of the base member that faces the internal space.

The invention provides a microwave drive control device. The microwave drive control device comprises a power converter; the first full-bridge inverter circuit is conductively connected with the power converter; the first voltage transformation circuit is connected with the first full-bridge inverter circuit in a conducting manner; the voltage doubling circuit is conductively connected with the first voltage transformation circuit; the magnetron is conductively connected with the voltage doubling circuit, and the magnetron is provided with a lamp filament; and the filament preheating circuit is conductively connected with the power converter and the filament of the magnetron, and the filament preheating circuit is used for preheating the filament before the high voltage is sent to the magnetron and is triggered after the filament is heated to a hot electron emission temperature. Through the filament preheating circuit, the filament can be preheated and then is driven by high voltage, so that the service life of the filament can be prolonged. In addition, the service life of the lamp filament is predicted by detecting the resistance value of the lamp filament and through a curve of the resistance value and the service life of the lamp filament.

The present invention belongs to the technical field of semiconductor material preparation. The wide bandgap nitride quantum well, preparation method and wide bandgap semiconductor device provided by the present application include a quantum well structure, wherein the quantum well structure includes a quantum well layer and a quantum barrier layer grown on the quantum well layer; nitrogen vacancies at the nitride quantum well heterointerface are introduced at the interface between the quantum well layer and the quantum barrier layer. The present application introduces precisely designed defect states into the quantum well. The energy level positions of these defect states are located near the quasi-energy level (Eg2) formed by CBM and CBM+1, which can effectively regulate the localized state density at CBM and VBM, promote balanced cooling of electrons and holes, and avoid non-radiative recombination effects caused by deep energy level defect states. At the same time, the introduction of defect states not only effectively reduces the hot electron cooling time, but also enhances the carrier injection and recombination efficiency, showing significant advantages compared with traditional EBL technology.

This invention provides the preparation and application of a dual LSPR effect nitrogen-fixing material with increased hot electron concentration at active sites. PMoV and Ag are attached to W via electrostatic self-assembly and photodeposition. 18 O 49 On the surface, Ag / W with dual LSPR effect was successfully prepared. 18 O 49 / PMoV heterojunction, experimental data show that W 18 O 49 It can absorb photogenerated electrons produced by PMoV and Ag, and the injected photogenerated electrons are in W 18 O 49 Enrichment at OVs on the surface, thus preserving W 18 O 49 Plasma effect, Ag / W 18 O 49 The fluorescence lifetime of photogenerated carriers in PMoV is prolonged, and the loading of Ag and PMoV is Ag / W. 18 O 49 / PMoV provides a new pathway for the migration of photogenerated electrons and holes, Ag / W 18 O 49 The nitrogen fixation activity of the / PMoV heterojunction was enhanced, and the ammonia generation rate reached 118.4 µmol g. −1 h −1 , is W 18 O 49 The yield is 3.6 times higher, and the experimental parameters are easy to control in this synthetic route.

The application relates to a solar heat absorber with self-power generation and heat storage functions and a running method thereof, and belongs to the technical field of solar heat absorbers. The heat absorber comprises a heat absorption pipe, an upper header tank, a lower header tank and a heat storage system, wherein a plurality of heat absorption pipes are arranged side by side between the upper header tank and the lower header tank, and the upper header tank and the lower header tank are respectively connected with the heat storage system; the wall of the heat absorption pipe is a multilayer structure, and from outside to inside, the multilayer structure comprises a hot electron anode, an electrode gap, a hot electron cathode and a heat transfer metal pipeline in sequence; the heat transfer metal pipeline circulates a heat transfer working medium; and the hot electron anode and the hot electron cathode are respectively connected with an external load through an anode lead wire and a cathode lead wire. The heat absorber has the function of power generation, can store heat by using concentrated light energy, and improves the efficiency and stability of the entire power generation system.

The invention relates to the technical field of biomedical sensing and wearable health monitoring, and discloses a photoelectrochemical sensing microneedle, a preparation method thereof, a monitoring system and a detection method. The sensing microneedle comprises a swellable dual-network hydrogel microneedle substrate, a three-dimensional conductive network and a semiconductor nanostructure, wherein the three-dimensional conductive network is composed of high-length-diameter-ratio metal nanowires with a local surface plasma resonance effect, and the semiconductor nanostructure is compounded on the surfaces of the metal nanowires and forms a Schottky heterojunction. The mechanical constraint of the rigid polymer skeleton and the high length-diameter ratio of the metal nanowire cooperate to ensure the continuity of the conductive network in a swelling state. Under the irradiation of exciting light, hot electrons are migrated to the surface of a semiconductor through a Schottky junction built-in electric field to generate reactive oxygen free radicals, non-enzymatic catalytic oxidation is carried out on a target analyte in interstitial fluid under zero bias voltage or low bias voltage, a photocurrent signal is generated, and integration of minimally invasive sampling and in-situ high-selectivity detection is realized.

An X-ray tube according to an embodiment includes a periphery that keeps the inside in vacuum, an anode target that generates X-rays by collision of hot electrons, and a cathode electron gun that emits the hot electrons to the anode target, and includes a periphery assembly that has a metal cylindrical support body fixing portion and constitutes the periphery, and a cathode assembly that has a metal support body that holds the cathode electron gun at a front end portion, and in the support body fixing portion, the support body of the cathode assembly is fixed at an inner peripheral side by welding.

This paper presents a low-interface-state gallium nitride (GaN) power device structure and fabrication method based on fluoride gate dielectric, belonging to the field of semiconductor device technology. Firstly, utilizing the principle of seamless filling in high aspect ratio structures, dielectric filling and repair are achieved in the deep recesses of the gate trench in the MIS recessed gate structure, suppressing electric field concentration at the corners and long-term device reliability degradation. Next, the principle of fluoride ion implantation is introduced to grow fluoride as the gate dielectric, improving current density while maintaining high interface quality and strong gate control capability, and reducing device instability caused by fluoride ion implantation. Secondly, fluoride is selectively grown in the gate region using magnetron sputtering, leveraging the advantages of fluoride treatment while ensuring device current density and on-resistance. The wide bandgap of fluoride can suppress hot electron injection under high electric field conditions, while the strong electronegativity of fluoride ions helps passivate the donor states on the GaN surface, forming better interface quality and improving gate leakage current and reliability degradation.

The invention provides a GaN HEMT (High Electron Mobility Transistor) device and a manufacturing method thereof, which are characterized in that at least one heat conduction hole is arranged in a field plate area corresponding to the GaN HEMT device, the heat conduction hole extends upwards from the back of the device and stops on the lower surface of a passivation layer on the surface of the device, and a heat conduction material is formed in the heat conduction hole and can conduct heat from a heating core of the device to the outside. According to the GaN HEMT device provided by the invention, the heat dissipation capability of the GaN HEMT device is effectively improved, the influence of a self-heating effect on the carrier mobility is reduced, the saturation leakage current and the reduction of transconductance are avoided, the gate leakage current and the hot electron damage are reduced, the reliability of the device is improved, and the service life of the device is prolonged.

An apparatus comprising: an ion trap, for example a 2 dimensional, 2D, ion trap such as a linear quadrupole ion trap, LIT, wherein the ion trap comprises a set of electrodes, for example wherein the 2D ion trap comprises two or more pairs of rod electrodes and optionally two end electrodes; a power supply configured to: generate a substantially rectangular radio frequency, RF, voltage waveform, wherein the RF voltage waveform includes a first set of states including a first state having a first voltage level and a second state having a second voltage level, wherein the first state and the second state are mutually opposed; and apply the generated RF voltage waveform to the set of electrodes, wherein the first set of states provides a trapping field in the ion trap for trapping ions in a trapping region thereof; an electron source, configured to inject electrons into the ion trap for reactions thereof with the ions, for example electron capture dissociation, ECD, hot ECD, electron induced dissociation, EID, and / or electron detachment dissociation, EDD; wherein the RF voltage waveform includes a second set of states including a first state having a first voltage level, wherein the first voltage level of the second set of states is between the first voltage level and the second voltage level of the first set of states; and wherein the electron source is configured to inject the electrons into the ion trap during the second set of states, for example only during the second set of states.

The application discloses a gallium nitride power device with a gate hot electron blocking structure, which comprises a substrate layer, a buffer layer, a channel layer and a barrier layer arranged in sequence from bottom to top; a first P-type material layer, a hot electron blocking structure layer, a second P-type material layer and a gate metal are sequentially arranged above the barrier layer; and a source metal and a drain metal are respectively arranged at both ends of the barrier layer. The barrier layer, the source metal part sidewall, the drain metal part sidewall, the first P-type material layer sidewall, the hot electron blocking structure layer sidewall, the second P-type material layer sidewall and the gate metal part sidewall are all covered with a passivation layer. The application introduces a hot electron blocking structure in the p-GaN gate gallium nitride power device, which can effectively prevent the movement process of hot electrons, thereby significantly reducing the bombardment damage of the hot electrons to the gate Schottky junction and improving the reliability of the device.

The invention discloses a Ni-doped Bi4O5Br2 bifunctional photocatalyst as well as a preparation method and application thereof. The preparation method of the photocatalyst comprises the following steps: dissolving a bismuth-containing compound in ethylene glycol to form a solution A; dissolving a bromine-containing compound in ethanol to form a solution B; dropwise adding the solution B into the solution A to form a solution C; adding a nickel-containing compound into the solution C to form a reaction solution; and transferring the reaction solution into a reaction kettle for heating, and after the reaction is completed, filtering, washing and drying to obtain Ni-doped Bi4O5Br2 powder. According to the invention, Ni is doped into Bi4O5Br2, the Bi4O5Br2 has double functions of LSPR effect and impurity energy level engineering, the LSPR effect of Ni enables infrared light to be converted into hot electrons and heat energy and provides thermodynamic driving force for CO2 activation, and Ni doping also generates impurity energy level which can capture carriers and effectively inhibit recombination of electrons and holes, so that the performance of the Bi4O5Br2 is improved. The carbon dioxide reduction effect of the photocatalyst is remarkably improved through the dual-function synergistic effect.

The invention discloses a wide-spectrum high-uniformity black silicon integrated nanogold quadrant detector and a preparation method thereof, the wide-spectrum high-uniformity black silicon integrated nanogold quadrant detector comprises a substrate base material, a micro-nano conical B-Si structure is etched on the substrate base material, gold nanoparticles are deposited and covered on the surface of the micro-nano conical B-Si structure, the photoelectric detector is a double-four-quadrant photoelectric detector, and the thickness of the double-four-quadrant photoelectric detector is larger than that of the micro-nano conical B-Si structure. And the boundary area of the double four quadrants is electrically isolated by etching deep grooves and filling oxygen-silicon compounds to form isolation grooves. The gold nanoparticles are compounded on the surface of B-Si, hot electrons can be excited through a localized surface plasma resonance mechanism and injected into a black silicon conduction band to participate in the photoelectric conversion process, the band gap limitation of the B-Si material is broken through, wide spectral response is achieved, the response capability in a near-infrared region is improved, and the photoelectric conversion efficiency is improved. And meanwhile, a silicon oxide and silicon nitride passivation film is introduced to the surface of the black silicon and gold nanoparticle composite structure, and a surface carrier recombination process is inhibited by filling dangling bonds and defect states on the surface of the black silicon pointed cone structure, so that the dark current level of the device is reduced.

The invention discloses a cascaded structure of a thermionic converter and an alkali metal thermoelectric converter, and relates to the technical field of power energy. Comprising a vacuum shell provided with a closed cavity capable of providing a vacuum environment; the thermionic emitter is mounted at one end of the sealed cavity and can be in contact with a heat source in a working state; the alkali metal thermoelectric converter is installed in the sealed cavity, a hot end electrode of the alkali metal thermoelectric converter is right opposite to the thermionic emitter, and the hot end electrode and the thermionic emitter are arranged at an interval; wherein the hot end electrode can receive hot electrons emitted by the thermionic emitter. The thermal ion converter (TIC) and the alkali metal thermoelectric converter (AMTEC) are integrated into a single device, so that intermediate heat loss can be avoided, the theoretical efficiency advantage of two-stage conversion can be brought into full play, and the total efficiency of the system is improved.

A weakly coupled enhanced graphene film includes an enhanced graphene structure based on weak coupling, wherein the enhanced graphene structure based on weak coupling comprises a plurality of graphene units stacked vertically; the graphene unit is a single graphene sheet, or consists of two or more graphene sheets stacked in AB form; two vertically adjacent graphene units are weakly coupled, to promote the hot electron transition and increase the joint density of states, thereby increasing the number of hot electrons in high-energy states; the stacking direction of the graphene units in the graphene structure is in the thickness direction of the graphene film; and the graphene film enhances the accumulation of hot electrons in high-energy states by the enhanced graphene structure based on weak coupling.

The application discloses polycrystalline lanthanum hexaboride and a preparation method and application thereof, and belongs to the technical field of lanthanum hexaboride preparation, and the preparation method comprises the following steps: ball milling mixed powders of lanthanum hexaboride powders and spherical nickel powders in a protective gas to prepare ball-milled powders; screening the ball-milled powders through an ultrasonic vibration sieve classifier, and collecting mixed powders with a particle size of 1-2 microns; placing the screened mixed powders in a mold, and then performing gradient hot-pressing sintering under vacuum conditions; and cooling after sintering to obtain the polycrystalline lanthanum hexaboride. The relative density of the material is as high as 99.42%, the material has the advantages of high density and strong thermal electron emission performance, the production cost of the method is low, the process difficulty is low, and the method can effectively solve the problems existing in the preparation of polycrystalline lanthanum hexaboride by using the existing sintering method.

The invention relates to a method and a system for automatically calculating Gibbs free energy of a material under different temperature and pressure conditions and constructing a phase diagram. The invention provides a method and a system for automatically calculating Gibbs free energy of a material and constructing a phase diagram. First principle calculation, phonon free energy calculation and hot electron free energy calculation are integrated into a unified automatic platform, so that the calculation efficiency is remarkably improved, and manual intervention is reduced. According to the system, firstly, static self-consistent energy is obtained through calculation according to a first principle, phonon free energy is calculated in combination with a quasi-harmonic approximation method, and hot electron free energy is obtained through electron state density analysis. On the basis, the compatibility among different calculation modules is ensured by adopting an automatic unit conversion and data preprocessing module. The system fits free energy-volume data through a three-order Birch-Murnaghan state equation, and supports adaptive encryption sampling so as to accurately capture phase change and free energy fluctuation under specific temperature and pressure conditions. Finally, the system automatically draws a temperature-pressure phase diagram, and an accurate basis is provided for predicting the thermodynamic stability of the material.

The invention belongs to the technical field of semiconductor materials, and particularly relates to a semiconductor material bismuth molybdate with a plasma effect and a preparation method and application thereof, Bi2 (NO3) 3.5 H2O and Na2MoO4. 2H2O are adopted as reaction raw materials, and a novel Bi2MoO6 material with the plasma effect is constructed through electron doping. The position of an oxygen hole can be accurately controlled between Mo and O-Mo in an ion doping mode, the position of the oxygen hole in Bi2MoO6 is accurately controlled, free electrons are captured by utilizing conversion of valence states of Mo < 6 + > / Mo < 5 + >, the concentration of the free electrons is improved, resonance with incident light is realized, a strong SPR effect is shown in visible and near-infrared regions, and the photoelectric conversion efficiency is improved. Meanwhile, high-activity hot electrons can be generated, the photocatalytic activity is effectively enhanced, and the photocatalyst has a huge application prospect in the field of photocatalysis.