Copper foam-derived electrodes as efficient electrocatalysts for conventional and hybrid water electrolysis

Electrochemical water splitting has been demonstrated as a promising technology for the renewable generation of green hydrogen from water.Despite the extensive progress in materials science,one particular challenge for further development towards industrial application lies in the rational design and exploitation of efficient and cost-effective materials,especially oxygen evolution reaction(OER)electrocatalysts at the anode.In addition,attempts to replace the OER with other more oxidizable anode reactions are being evaluated as a groundbreaking strategy for generating hydrogen at lower potentials and reducing overall energy costs while producing valuable chemicals simultaneously.Compared with Fe/Co/Ni-based compounds,Cu-based materials have not received extensive research attention for electrode designs despite their high conductivity and abundant earth reserves.In this review,combining with the advantages of a three-dimensional network structure of metal foams,we summarize recent progress on Cu foam(CF)-derived materials as efficient electrocatalysts towards pure water electrolysis and hybrid water electrolysis.The advantages of CF and design strategies to enhance the electrocatalytic activity and operational durability are presented first.Catalyst design and fabrication strategies are then highlighted and the structure-activity relationship is also discussed.Finally,we propose challenges and perspectives on self-supported electrodes beyond CF-derived materials.

Recent advances in hybrid water electrolysis for energy-saving hydrogen production

Electricity-driven water splitting to convert water into hydrogen(H_(2)has been widely regarded as an efficient approach for H_(2)production.Nevertheless,the energy conversion efficiency of it is greatly limited due to the disadvantage of the sluggish kinetic of oxidation evolution reaction(OER).To effectively address the issue,a novel concept of hybrid water electrolysis has been developed for energy–saving H_(2)production.This strategy aims to replace the sluggish kinetics of OER by utilizing thermodynamically favorable organics oxidation reaction to replace OER.Herein,recent advances in such water splitting system for boosting H_(2)evolution under low cell voltage are systematically summarized.Some notable progress of different organics oxidation reactions coupled with hydrogen evolution reaction(HER)are discussed in detail.To facilitate the development of hybrid water electrolysis,the major challenges and perspectives are also proposed.

Reducing Energy Costs during Hydrogen Production from Water Electrolysis by Coupling Small Molecule Oxidation: From Molecular Catalysis to Industrial Exploration

Hydrogen energy has garnered significant attention in recent years as a solution to address the global energy crisis and environmental pollution.While water electrolysis stands out as the most promising method to produce green hydrogen,the sluggish reaction kinetics of the oxygen evolution reaction(OER)on the anode increases the cost of hydrogen production.One potential solution to this challenge is replace OER with the thermodynamically more favorable oxidation of small molecules,which can efficiently reduce the energy cost while simultaneously yielding high-value chemicals.Up to now,various organic oxidation reactions have been reported to couple with hydrogen evolution,including alcohol oxidation,biomass platform molecule upgrading,and sacrificial reagents oxidation associated with wastewater treatments.This review concentrates on the recent advancements in the mechanism,catalyst,reactor,and process in this field,with a discussion on its prospects for commercialization.