Recent developments, advances and strategies in heterogeneous photocatalysts for water splitting

Abstract

Photocatalytic water splitting (PWS) is a highly promising technique for generating sustainable fuel by using light energy. Significant progress has been made in the development of PWS innovations over recent...

Boosting Urea-Assisted Natural Seawater Electrolysis in 3D Leaf-Like Metal–Organic Framework Nanosheet Arrays Using Metal Node Engineering

“…282 kJ mol −1 ) and carbon-free emission. 2,3 Over the past decade, a lot of studies have used natural seawater as feedstock instead of desalinated freshwater for electrolysis to realize a net-zero emission society, aiming to reduce the cost of green hydrogen production due to the endless and cost-free natural seawater. 4,5 However, commercialization of natural seawater electrolysis technology faces significant challenges, especially anode corrosion by side product Cl − at high current density and the blockage of active sites by insoluble precipitates (Ca(OH) 2 and Mg(OH) 2 ) at the cathode site.…”

“…Green hydrogen, produced during electrochemical water splitting, has emerged as an energy source capable of replacing fossil fuels due to its remarkable properties, such as high energy density (ca. 282 kJ mol –1 ) and carbon-free emission. , Over the past decade, a lot of studies have used natural seawater as feedstock instead of desalinated freshwater for electrolysis to realize a net-zero emission society, aiming to reduce the cost of green hydrogen production due to the endless and cost-free natural seawater. , However, commercialization of natural seawater electrolysis technology faces significant challenges, especially anode corrosion by side product Cl – at high current density and the blockage of active sites by insoluble precipitates (Ca­(OH) 2 and Mg­(OH) 2 ) at the cathode site. , In addition, the sluggish kinetics of the oxygen evolution reaction (OER), which deteriorates the performance of overall seawater splitting, is another major bottleneck for its implementation. , One way to resolve the fundamental bottleneck of the above-mentioned issue is to substitute traditional OER with a thermodynamically more favorable urea oxidation reaction (UOR) and hydrazine oxidation reaction (HzOR). − Some early attempts at urea-assisted seawater splitting have demonstrated the practical improvement of catalytic efficiency. , Nowadays, considerable efforts have been dedicated to catalyst development, understanding fundamental chemical mechanisms, and technological innovations over the past few years, resulting in highly efficient, low-synthesis-cost, and long-lifetime bifunctional electrocatalysts for overall urea-assisted seawater electrolysis. Unfortunately, a trade-off dilemma between increased efficiency and decreased cost remains the major bottleneck for large-scale hydrogen production.…”