38 results about "Molecular junction" patented technology

The invention provides a method for preparing a molecular junction by polydimethylsiloxane stencil printing, which comprises the following steps: cleaning a Si substrate, and then, carrying out photoetching; preparing a lower electrode; preparing a molecular self-assembly film on the surface of the Au lower electrode; preparing a polydimethylsiloxane stencil; preparing a polydimethylsiloxane seal; preparing an upper electrode; and then, carrying out upper electrode printing to obtain a crossed molecular junction. The invention provides a non-destructive preparation method of an upper electrode of a crossed molecular junction of an organic molecular layer, thereby avoiding the defects that when an Au film is directly deposited on the organic molecular layer, the upper electrode and the lower electrode are in short circuit because a small amount of metal particles penetrate into pores among molecules or ablative degradation is caused because of the evaporated and deposited heat. The method provided by the invention effectively avoids the serious uncertainty among metal / molecule contact interfaces.

The invention discloses a method for detecting small organic biological molecules and a special graphene electrode-based DNA (deoxyribonucleic acid) unimolecular connecting device. The DNA unimolecular connecting device is prepared by the following method: 1) constructing a molecular device with graphene electrodes; 2) treating the grapheme molecular device obtained in step 1) so as to obtain nano-gaps of 1-10nm; 3) connecting a designed DNA sequence to the nano-gaps of a cutting device, thus obtaining a DNA unimolecular connecting device. And detection method consists of: using the prepared DNA unimolecular connecting device to combine with and identify small organic biological molecules for electric signal detection, excluding various interference factors; subjecting the small organic biological molecules to sensitivity and other tests in the device; determining a measuring condition according to the test results of the above steps so as to realize detection of the small organic biological molecules in the connecting device. The method of the invention makes use of a functionalized unimolecular device to realize high sensitivity detection of small organic biological molecules through electric signals.

The present invention discloses a protein transistor device, wherein an antibody molecule (antibody-antigen) is bonded to at least two gold nanoparticles in a high reproducible self-assembly way to form molecular junctions, and wherein the two gold nanoparticles are respectively joined to a drain and a source. The protein transistor device can be controlled to regulate current via applying a bias to the gate. The conformational change of the protein molecule will cause the variation of the charge transport characteristics of the protein transistor device. The protein transistor device can be further controlled by different optical fields via conjugating a quantum dot to the molecular junctions. Therefore, the present invention has diversified applications.

The invention discloses a reaction kinetics measurement method based on single molecule electrical detection, and involves a chemical reaction kinetics measurement method. The method comprises the following steps: mixing molecular solid and a solvent, and obtaining a molecular solution; placing a chip under a microscope, aligning a blade with a metal wire, firstly conducting cross-cutting, and then cutting the metal wire through a tip of the blade to get the chip; installing the chip, a reaction pool, an O-ring and a seal cover; opening a motor, passing the blade to an incision through the upper top of the motor, and fracturing to form a nano-gap; conducting an in situ test, data record and data analysis, when the metal atoms point contact is disconnected and an electrode is formed; and conducting statistics on the distance between the step and the end in a conductance-distance curve, obtaining a column-like statistical chart, providing another dimension information for an electrical measurement of a molecular junction by the conductance-distance curve, observing changes in conductance in a BJ process when the molecular junction is stretched and closed with the electrode pair, obtaining the interval size opened by the electrode pair, and ultimately inferring the evolution information that the molecular junction conductance changes with the distance.

Forward and back electron transfer at molecule oxide interfaces are pivotal events in dye-sensitized solar cells, dye-sensitized photoelectrosynthesis cells and other applications. Disclosed herein are self-assembled multilayers as a strategy for manipulating electron transfer dynamics at these interfaces. The multilayer films are achieved by stepwise layering of bridging molecules, linking ions, and active molecule on an oxide surface. The formation of the proposed architecture is supported by ATR-IR and UV-Vis spectroscopy. Time-resolved emission and transient absorption establishes that the films exhibit an exponential decrease in electron transfer rate with increasing bridge length. The findings indicate that self-assembled multilayers offer a simple, straight forward and modular method for manipulating electron transfer dynamics at dye-oxide interfaces.

The invention discloses a preparation method of an addressable nano molecular junction, belonging to the field of micro machining of nano materials and testing of nano electronic devices. The preparation method comprises the steps of: firstly, washing a piezoelectric ceramic substrate; preparing an insulation layer film on the piezoelectric ceramic substrate and obtaining a micro nano strip-shaped bulge on the middle; preparing a narrow-neck-shaped Au electrode film layer on the insulation layer film; placing the piezoelectric ceramic substrate in a vacuum chamber, respectively welding leads on two sides of the piezoelectric ceramic substrate and leading out a vacuum chamber; electrifying the piezoelectric ceramic substrate to ensure that the Au electrode film layer is broken to obtain a metal electrode pair with a nano gap; and finally, filling an organic molecular material in the nano electrode gap to obtain the addressable nano molecular junction. According to the invention, the gap controllable nano Au electrode pair is obtained through regulating bias voltages and electrifying time of two ends of the piezoelectric ceramic substrate, thus pollution and thermally induced ablation on a metal molecular interface when electrodes deposit on a molecular layer are avoided through molecule self-assembly in the gap.

The invention discloses an STM-BJ-based monomolecular junction thermoelectric potential measurement method and STM-BJ-based monomolecular junction thermoelectric potential measurement equipment. A Seebeck coefficient of a molecular junction is obtained by acquiring a single molecule, verifying the single molecule, measuring a thermal voltage, verifying the single molecule, repeatedly acquiring a plurality of pieces of data, and then carrying out corresponding statistics and calculation. A stable and easily-adjusted heat source is provided for a substrate based on an STM-BJ technology, so thatthe temperature difference is constructed at the two ends of the molecular junction, an independent voltage amplifier is introduced to measure the electromotive force generated by the temperature difference after the molecular junction is formed, and therefore measurement of the thermoelectric potential of the monomolecular junction is achieved. Compared with an MCBJ technology and an STM-BJ needle tip temperature control technology, the research means has the advantages of being simple, efficient, wide in adjustable range, high in error-tolerant rate and the like, the measurement efficiency of the monomolecular junction thermoelectric potential is greatly improved, research and development of a novel organic thermoelectric material are promoted, and powerful assistance is provided for thesociety where the energy urgently needs to be changed.