Preparation Of Co-LDHs And PtCo/C Composites For Their Electrocatalytic Performance

The development of a simple,low-cost synthetic strategy to prepare high-performance catalysts provides a reliable guarantee for large-scale applications.Among them,the preparation of alloys by non-noble metals to reduce the noble metal content is a common method.Additionally,recyclable strategies is an effective means to reduce resource loss and environmental pollution.The research of this work mainly includes the following two aspects.（1）Layered double hydroxides（LDHs）have a typical hierarchical structure and have been widely used as electrocatalysts in oxygen evolution reaction in recent years.Imidazolate-assisted production of cobalt layered double hydroxide（Co-LDH）with different assembled structures is presented.And at different temperatures,the reversible cyclic transformation of Co-LDHs with ZIF-67 was successfully completed,and Co²⁺was efficiently used.The porous Co-LDHs exhibited significant OER performance that the overpotential was 312 mV at 10 m A·cm^-2 and the cage-like Co-LDHs by ZIF-67 conversion obtained similar electrocatalytic properties.When the multilayer structure was disassembled,it exhibited more excellent electrocatalytic properties,reaching an overpotential of 288-290mV at 10 m A·cm^-2.Importantly,the reversible/cycling transformation Co-LDHs and ZIF-67provides an effective way to fundamentally reduce pollutant emissions and resource consumption.（2）Due to the high price and scarcity of noble metals,they cannot be put into substantial production.Therefore,how to reduce the content of noble metals in electrocatalytic hydrogen evolution materials and maintain their high catalytic activity has become a research hotspot in water electrolysis.ZIF-67 was mixed with sodium chloroplatinate and L-alanine,which finally were reduced to PtCo alloy and formed PtCo/C composite structure.In acid electrolyte,it obtained an overpotential of 42 mV at 10 m A·cm^-2,close to 32 mV of Pt/C material.The strong electronic effect between its interfaces can provide high active sites for electrocatalytic reactions.This provides an effective method for preparing highly active and energy-saving electrocatalysts and it is an effective way to realize large-scale hydrogen evolution.