Construction of stamen-type s-doped manganese-copper electrocatalysts based on metal polyphenol-modified sodium alginate/nanocellulose composite aerogels

Abstract

The invention discloses a stamen-type S-doped manganese-copper electrocatalyst based on metal polyphenol modified sodium alginate / nanocellulose composite airgel, and the manganese-copper electrocatalyst is C@MnOCu 7.2 S 4 -TA. The nanocellulose prepared by the acid hydrolysis method introduces a large amount of sulfur doping, and the three-dimensional network structure of the sodium alginate / nanofiber composite airgel has a large number of pores as a porous carbon template, which increases the contact area with the precursor metal solution, making the tannin The modified metal polyphenol network is uniformly distributed in the sodium alginate / nanofiber composite airgel. The nanocomposite material synthesized after high temperature carbonization presents a stamen shape. The invention is used to solve the shortcomings of existing fuel cell catalysts, such as low reversibility of cathode oxygen reduction reaction, small exchange current density, high cost of Pt-based catalytic materials and poor toxicity resistance, etc. The obtained oxygen reduction catalyst has high potential, Excellent limiting current and high methanol tolerance and other advantages.

Description

Technical field [0001] The present invention belongs to the field of proton membrane fuel cell catalyst technology, specifically relates to a kind of metal polyphenol modified sodium alginate / nanocellulose composite aerogel to construct a flower-type S-doped manganese copper electrocatalyst. Background [0002] At present, proton membrane fuel cells (PEMFC) are facing problems such as high cost and short life, which makes it impossible to achieve wide application, which limits the further development of PEMFC in the industrialization process. Nowadays, in order to improve the performance of PEMFC and reduce the cost of catalyst, one of the main ways is to reduce the use of precious metal Pt by changing the carrier and preparing alloy catalysts from the perspective of catalyst intrinsic activity to improve catalyst activity and stability. [0003] Nanocellulose comes from a wide range of sources, i.e. because it contains a large amount of hydroxyl groups, a stable positive or ne...

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Problems solved by technology

[0005] The purpose of the present invention is to solve the problems existing in the existing fuel cell catalysts and overcome the defects of the prior art. At present, the fuel cell catalysts generally face the single obstacle of the precursor and the problem of synthesis cost; nanocellulose based on sulfuric acid hydrolysis introduces a large amount of sulfur Doping, using sodium alginate as a support to prepare sodium alginate / nanofiber composite airgel, the metal polyphenol network modified by tannin is evenly distributed in the sodium alginate / nanofiber composite airgel, after high temperature carbonization The synthesized nanocomposite C@MnOCu 7.2 S 4 -TA is in the shape of a stamen, and it has the advantages of high initial potential, half-slope potential, excellent limiting current, good methanol tolerance, and strong resistance to methanol poisoning when it is applied to oxygen reduction electrocatalysts.

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