A kind of strong ligand-controlled growth of ultrafine three-dimensional platinum nanowire arrays on substrates and methods thereof

Abstract

The invention relates to a technology for directly growing a three-dimensional platinum nanowire array on a substrate under the control of strong ligands at room temperature. The obtained platinum nanowire array has uniform distribution, high repeatability, and uniform length, density and surface roughness. Controllable, and finally the conductive substrate longer than the platinum wire can be directly used as a working electrode for methanol fuel cell testing, which has higher activity and stability than commercial platinum carbon. The raw materials required by the invention are simple and easy to obtain, the operation process is simple and safe, the cost is low, the catalytic activity is high, and the stability is good.

Description

technical field [0001] The present invention relates to a technique for growing ultrafine platinum nanowire arrays directly on conductive materials such as conductive glass, carbon paper, carbon cloth and other substrates. Since platinum-based material is an excellent catalyst, the structure can be used in fuel cells such as methanol fuel cells and proton exchange membrane cells, and has good catalytic activity and stability. Background technique [0002] In recent years, fuel cells have developed rapidly due to their advantages of high energy conversion efficiency and no emission of harmful substances, but there are still some technical barriers that are the activity and stability of their catalysts. According to literature reports, the best catalyst currently used for fuel cells is 1-3 nm platinum nanoparticles supported on carbon black. However, due to the high surface energy of this catalyst, it is prone to aging and aggregation during the test process. Moreover, the ca...

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Problems solved by technology

Through reviewing the literature, it is found that due to the large energy difference between the crystal planes of platinum metal, it is difficult to form various structures, especially one-dimensional structures, so the current methods for synthesizing one-dimensional platinum nanowires are still very limited. , the method of synthesizing better morphology is mainly through the method of high-temperature oil bath, but this method is relatively harsh at first, and it also takes a long time. Synthesize some free-standing platinum wires, and these wires still have big problems when they are used in electrochemical tests later. First, these nanomaterials must be adhered to conductive materials through the action of binders. Nanowires will inevitably pile up and consume part of the electrochemically active area, and the use of binders will affect electron transport, thereby reducing catalytic activity, so a three-dimensional nanowire that can be grown directly on a conductive substrate is invented. The structure of the line array is very important, and the current synthesis method for the three-dimensional platinum nanowire array is still very limited, mainly through the method of template and electrodeposition. For example, an article in 2009 introduced a PC film as a template. , synthesized 30nm thick platinum nanotubes at room temperature (J.Phys.Chem.C, Vol.113, No.14, 2009), an article in 2018 introduced a method using AAO as a template by electrodeposition A platinum nanowire array with a direct diameter of 200nm and a length of 2μm was synthesized (ACS Appl. Energy Mater. 2018, 1, 3973-3983), and these methods rely on templates or electrodeposition methods to synthesize platinum nanowire arrays, while platinum nanowires The diameter of the wire array is large, which not only consumes a large amount of platinum but also is not conducive to the improvement of electrochemical activity

In addition, the above methods are mainly synthesized by electrodeposition, which requires the use of corresponding electrochemical equipment, which is relatively time-consuming and expensive.

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