Kim Jin Hyun, Hwang Soo Min, Hwang Inchan, Han Jinhyup, Kim Jeong Hun, Jo Yim Hyun, Seo Kwanyong, Kim Youngsik, Lee Jae Sung
Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan 44919, Republic of Korea.
Department of Energy Engineering, School of Energy and Chemical Engineering, Ulsan National Institute of Science & Technology (UNIST), Ulsan 44919, Republic of Korea.
iScience. 2019 Sep 27;19:232-243. doi: 10.1016/j.isci.2019.07.024. Epub 2019 Jul 19.
Conversion of sunlight to chemical energy based on photoelectrochemical (PEC) processes has been considered as a promising strategy for solar energy harvesting. Here, we propose a novel platform that converts solar energy into sodium (Na) as a solid-state solar fuel via the PEC oxidation of natural seawater, for which a Na ion-selective ceramic membrane is employed together with photoelectrode (PE)-photovoltaic (PV) tandem cell. Using an elaborately modified bismuth vanadate-based PE in tandem with crystalline silicon PV, we demonstrate unassisted solar-to-Na conversion (equivalent to solar charge of seawater battery) with an unprecedentedly high efficiency of 8% (expected operating point under 1 sun) and measured operation efficiency of 5.7% (0.2 sun) and long-term stability, suggesting a new benchmark for low-cost, efficient, and scalable solid solar fuel production. The sodium turns easily into electricity on demand making the device a nature-friendly, monolithic solar rechargeable seawater battery.
基于光电化学（PEC）过程将太阳光转化为化学能被认为是一种很有前景的太阳能收集策略。在此，我们提出了一种新型平台，该平台通过对天然海水进行PEC氧化将太阳能转化为固态太阳能燃料钠，为此采用了钠离子选择性陶瓷膜与光电极（PE）-光伏（PV）串联电池相结合的方式。通过将精心修饰的钒酸铋基光电极与晶体硅光伏电池串联使用，我们展示了无辅助的太阳能到钠的转化（相当于海水电池的太阳能充电），其效率高达8%（1个太阳光照下的预期工作点），实测运行效率为5.7%（0.2个太阳光照），并且具有长期稳定性，这为低成本、高效且可扩展的固态太阳能燃料生产树立了新的标杆。钠可根据需求轻松转化为电能，使该装置成为一种对环境友好的单片式太阳能可充电海水电池。
