Exploiting dual-functional photoelectrodes to harvest and store solar energy is a challenging but efficient way of achieving renewable energy utilization. Herein, TiO2@MoS2@C multi-heterostructures with photoelectric conversion and electronic transmission interfaces are designed as dual-functional photoelectrode for ultra-fast sodium ion storage. When assembled to photo sodium ion battery (photo-SIB), its capacity increases to 444.1 mAh g-1 with a high photo-conversion efficiency of 0.71% switching from dark to visible light at 2.0 A g-1. Remarkably, the photo-SIB can be recharged only by light and provide a striking capacity of 231.4 mAh g-1. Experimental and theoretical results confirm the multi-heterostructures can enhance sodium ion storage kinetics, ensure structural stability, and facilitate photo-excited carrier separation and transmission under light. This work presents a brand-new strategy to design dual-functional photoelectrodes for efficient solar harvesting and storage.
Published in: "Angewandte Chemie International Edition".