Efficient Sb<sub>2</sub>S<sub>3</sub> and Low Se Content Sb<sub>2</sub>Se<sub><i>y</i></sub>S<sub>3–<i>y</i></sub> Indoor Photovoltaics
Rui Cao, Kai Lv, Chengwu Shi, Yanqing Wang, Changsheng Ye, Fuling Guo, Guiju Hu, Wangchao Chen
Abstract
Herein, the precise fabrication of Sb 2 S 3 and low Se content Sb 2 Se y S 3– y indoor photovoltaics is reported, and a measurement protocol for photovoltaic performance is suggested and applied. Insertion of the SnO 2 buried layer decreases the thickness and parasitic absorption of the CdS layer. The introduction of minor Se into Sb 2 S 3 and the use of spiro -OMeTAD:TMT-TTF improve the charge transport of indoor photovoltaics. Using a white light-emitting diode (LED) under illuminance of 1000, 500, and 200 lx with color temperatures of 3347 and 6103 K, indoor photovoltaics with fluorine doped tin oxide (FTO)/SnO 2 (17 nm)/CdS (20 nm)/Sb 2 S 3 / spiro -OMeTAD:TMT-TTF/Au exhibit power conversion efficiency (PCE) values of 17.59, 16.66, 16.44, 16.56, 15.50, and 14.07%, respectively. Indoor photovoltaics with FTO/SnO 2 (17 nm)/CdS (20 nm)/Sb 2 Se y S 3– y (Sb/S/Se = 1:1.42:0.06)/ spiro -OMeTAD:TMT-TTF/Au achieve PCE values of 18.53, 17.62, 17.07, 17.30, 16.24, and 15.38%, respectively. The PCE values of 17.59, 16.66, and 16.44% are the highest values reported for Sb 2 S 3 indoor photovoltaics, and the other PCEs are all reported for the first time. Considering the trillion-dollar-sized market from the Internet of Things (IoT), this work can further bring an unprecedented thrust to the development of self-powered IoT devices by harvesting energy from indoor photovoltaics, thereby realizing the recycling of photon energy and reducing the use of batteries and the emission of CO 2 .