Photoelectrochemical seawater oxidation with metal oxide materials:Challenges and opportunities

Photocatalytic water oxidation is a crucial counter-electrode reaction in the process of photoelectrochemical energy conversion.Despite its importance,challenges remain in effectively and sustainably converting water to oxygen,particularly with readily available and inexpensive electrolyte solutions such as seawater.While metal oxide materials have demonstrated their advantages in promoting efficiency by reducing overpotential and improving light utilization,stability remains limited by corrosion in multicomponent seawater.In this paper,we reviewed the relationship between four basic concepts including photoelectrochemistry,metal oxide,water oxidation and seawater to better understand the challenges and opportunities in photoelectrochemical(PEC)seawater oxidation.To overcome these challenges,the advances in material design,interfacial modification,local environment control and reactor design have been further reviewed to benefit the industrial PEC seawater oxidation.Noticeably,we demonstrate engineered layered metal oxide electrodes and cell structures that enable powerful and stable seawater oxidation.We also outline and advise on the future direction in this area.

Developing silicon-based photocathodes for CO_(2) conversion

Photoelectrochemical(PEC)conversion of CO_(2) presents a promising avenue for solar-driven chemical fuel production,with silicon emerging as a cost-effective and high-light-absorbing material pivotal to this technology.Aiming at exploring opportunities for industrializing PEC CO_(2) reduction(PEC-CO_(2)R)by minimizing reaction energy consumption,enhancing reaction efficiency and selectivity,this review summarizes recent advancements in developing Si-based photocathodes for PEC-CO_(2)R.It outlines the fundamental principles,advantages,and limitations of Si photocathodes with key performance metrics.Based on this understanding,the strategies to enhance the performance of the PEC-CO_(2)R system,including light absorption,charge separation,and catalytic reactions are categorized as the interfacial modification,active site decoration,and protective layer design.The design ideas of this advantageous three-layer structure in promoting the efficiency,stability,and selectivity have been clarified.Then,this review scrutinizes the influence of the photocathodic chemical environment.This review consolidates the mechanism insights and notable breakthroughs of various fuel generation processes within Si-based PEC-CO_(2)R systems.Providing this wealth of information offers an up-to-date perspective on the dynamic developments in silicon-based PEC-CO_(2) conversion and underscores the promising pathways toward the sustainable fuel synthesis from pollutant CO_(2).