Pivotal Role of Chirality in Photoelectrocatalytic (PEC) Water Splitting

For decades, the over-exploitation of fossil fuel has made it urgent to develop alternative energy. Photoelectrochemical (PEC) water splitting is a promising approach to generate hydrogen, which is referred to as the fuel of the future due to its high enthalpy of combustion and zero pollution. Though impressive progress has been made over the years, PEC water splitting efficiency is still far from volume production of hydrogen, and more efforts are required to reduce the overpotential, inhibit the yield of hydrogen peroxide by-product, improve the PEC current density, improve light-harvesting capability, and develop low-cost earth-abundant catalysts. Recently, chirality has shown to play a pivotal role in addressing the issues of PEC water splitting via the effect of chiralinduced spin controlling and chiral-enhanced light harvesting. It is high time to pay attention to the art of chirality in promoting water splitting efficiency. Herein, recent progress in this field is reviewed, the approaches to introducing chirality into photo/electronic catalysts for PEC water splitting are summarized, characterization techniques applied in this research field are summed up, the challenges of chirality-enhanced PEC water splitting are discussed, and based on the present achievements, its bright future is anticipated.