Metal organic frameworks derived single atom catalysts for electrocatalytic energy conversion

The development of efficient and cost-effective catalysts to catalyze a wide variety of electrochemical reactions is key to realize the large-scale applicati on of ren ewable and clean en ergy tech no logies.Owing to the maximum atom-utilization efficie ncy and unique electronic and geometric structures,single atom catalysts(SACs)have exhibited superior performance in various catalytic systems.Recently,assembled from the function alized orga nic lin kers and metal no des,metal-organic frameworks(MOFs)with ultrafi ne porosity have received treme ndous attention as precursors or self-sacrificing templates for preparing porous SACs.Here,the recent advances toward the synthesis strategies for using MOF precursors/templates to con struct SACs are systematically summarized with special emphasis on the types of central metal sites.The electrochemical applications of these recently emerged MOF-derived SACs for various energy-conversion processes,such as oxygen reduction/evolution reaction(ORR/OER),hydrogen evolution reaction(HER),and CO2 reduction reaction(CO2RR),are also discussed and reviewed.Fin ally,the curre nt challe nges and prospects regardi ng the developme nt of MOF-derived SACs are proposed.

Interfacial engineering of SnO_(2)/Bi_(2)O_(2)CO_(3)heterojunction on heteroatoms-doped carbon for high-performance CO_(2)electroreduction to formate

Electrochemical CO_(2)reduction is a viable,economical,and sustainable method to transform atmospheric CO_(2)into carbon-based fuels and effectively reduce climate change and the energy crisis.Constructing robust catalysts through interface engineering is significant for electrocatalytic CO_(2)reduction(ECR)but remains a grand challenge.Herein,SnO2/Bi_(2)O_(2)CO_(3)heterojunction on N,S-codoped-carbon(SnO_(2)/BOC@NSC)with efficient ECR performance was firstly constructed by a facile synthetic strategy.When the SnO_(2)/BOC@NSC was utilized in ECR,it exhibits a large formic acid(HCOOH)partial current density(JHCOOH)of 86.7 mA·cm^(−2)at−1.2 V versus reversible hydrogen electrode(RHE)and maximum Faradaic efficiency(FE)of HCOOH(90.75%at−1.2 V versus RHE),respectively.Notably,the FEHCOOH of SnO_(2)/BOC@NSC is higher than 90%in the flow cell and the JHCOOH of SnO_(2)/BOC@NSC can achieve 200 mA·cm^(−2)at−0.8 V versus RHE to meet the requirements of industrialization level.The comparative experimental analysis and in-situ X-ray absorption fine structure reveal that the excellent ECR performance can be ascribed to the synergistic effect of SnO_(2)/BOC heterojunction,which enhances the activation of CO_(2)molecules and improves electron transfer.This work provides an efficient SnO_(2)-based heterojunction catalyst for effective formate production and offers a novel approach for the construction of new types of metal oxide heterostructures for other catalytic applications.

3D ordered macro-/mesoporous Ni_(x)Co_(100-x ) alloys as high-performance bifunctional electrocatalysts for overall water splitting

Electrochemical water splitting is a facile and effective route to generate pure hydrogen and oxygen.However,the sluggish kinetics of hydrogen evolution reaction(HER) and especially oxygen evolution reaction(OER) hinder the water splitting efficiency.Meanwhile,the high-cost of noble-metal catalysts limit their actual application.It is thus highly urgent to exploit an economical and earthabundant bifunctional HER and OER electrocatalyst to simplify procedure and reduce cost.Herein,we synthesize the three-dimensionally ordered macro-/mesoporous(3 DOM/m) Ni_(x)Co_(100-x) alloys with distinctive structure and large surface area via a dual-templating technique.Among them,the3 DOM/m Ni61Co39 shows the lowest overpotentials of 121 mV and 241 mV at 10 mA/cm^(2) for HER and OER,respectively.Furthermore,when employed for water splitting,the Ni_(61)Co_(39) only requires 1.60 V to approach 10 mA/cm^(2) and presents excellent stability.These encouraging performances of the Ni_(61)Co_(39) render it a promising bifunctional catalyst for overall water splitting.