Role of Copper Doping in Heavy Metal‐Free InP/ZnSe Core/Shell Quantum Dots for Highly Efficient and Stable Photoelectrochemical Cell

Abstract

Abstract As emerging eco‐friendly alternatives to traditional Cd/Pb‐based quantum dots (QDs), InP/ZnSe(S) core/shell QDs have demonstrated huge potential in light‐emitting technologies. So far, these QDs have been rarely employed in solar energy conversion applications due to their type‐I band structure offering limited photo‐induced charge carrier separation and transfer. Here, a controllable Cu shell doping approach is reported to engineer the optoelectronic properties of InP/ZnSe core/shell QDs and realize high performance and stable solar‐driven photoelectrochemical (PEC) hydrogen evolution. As compared to the pristine InP/ZnSe QDs, the Cu‐doped core/shell QDs exhibit enhances the photo‐induced electron transfer rate due to the capture of photo‐generated holes via Cu impurity states in the shell, leading to improved photocurrent density and long‐term durability in as‐fabricated InP/ZnSe:Cu QDs‐PEC devices under standard one sun illumination. The results indicate that the doping of Cu in the shell has a preeminent effect on the optoelectronic properties of the core/shell QDs and may open up new avenues to tailor eco‐friendly core/shell QDs for high performance and stable solar energy conversion.