Multiplying Light Harvest Driven by Hybrid-Reflections 3D Electrodes Achieves High-Availability Photo-Charging Zinc-Ion Batteries

摘要

Independent photo-charging technologies based on aqueous zinc-ionbatteries (ZIBs) are promising candidates for next-generation renewableenergy systems. The conflict between light utilization and electrochemicalperformance in the planar electrode severely limits the availability of photochargingZIBs. Herein, 3D light-trapping structures (LTSs) are proposed andapplied in a rigid VO2/C@SiCuOC electrode. A hybrid-reflection effect drivenby LTSs is employed to improve light-harvesting efficiency. The suitableenergy levels of VO2 and C ensure charge transport, while the rigid SiCuOCsupport meets the stability requirements. Such a 3D VO_2/C@SiCuOC electrodeexhibits a multiplying photo-response current density of 42.2 μA cm~(?2)(≈400% of the plate) and delivers a higher energy density (0.19 mWh cm?2 at0.51 mW cm~(?2)). More importantly, in a realistic environment (dark for 16 hand light for 8 h), the photo-charging ZIBs integrated into a roof exhibit anexciting open circuit voltage of 3.176 V (three in series) and supply electricitycontinuously. The high strength (over 9 Mpa) of the photo-charging ZIBsinherited from the 3D rigid electrode further enables its practical application.The enhanced performance of the photo-charging ZIBs obtained fromstructural optimization provides unique inspiration for next-generation cleanenergy harvest/storage systems.