Synthesis and Characterization of an Efficient Hole-Conductor Free Halide Perovskite CH 3 NH 3 PbI 3 Semiconductor Absorber Based Photovoltaic Device for IOT

Abstract

© The Author(s) 2018. Organometal halide perovskite (CH3NH3PbI3) absorber was synthesized from CH3NH3I and PbI2in N, N dimethylformamide by solution spin coating process. Characterization by X-ray diffraction, optical and electron microscopy studies confirmed a well-formed nano-crystalline tetragonal pervoskite structure. The synthesized CH3NH3PbI3was used as a photo absorber material in a hole-conductor free photovoltaic device with TiO2as an electron conductor. This configuration of the perovskite photovoltaic device exploits the role of CH3NH3PbI3simultaneously as light absorber and hole-conducting material. We report two device configurations: (a) with a compact TiO2buffer layer introduced between the porous TiO2and FTO and (b) without the compact TiO2layer over the FTO substrate. The simple solar cell structure FTO/TiO2/CH3NH3PbI3/Agpresented here shows good photovoltaic performance under illumination with standard AM1.5 sunlight. For the champion devices from the two structures, (a) and (b), we obtained short circuit photocurrent densities asJsc= 17.4 mA/cm2and 19.5 mA/cm2, open circuit voltage Voc= 1.0 V and 1.45 V, fill factor FF = 0.54 and 0.29 and a power conversion efficiency (PCE) of 9.39% and 8.19% respectively under solar light intensity flux of 100 mW/cm2. We find that structure (a) offers significantly better device parameters. The results of the present work suggest a route to realize a simple, low cost and highly efficient perovskite photovoltaic device. These devices could be realized in miniaturized sensors and electronic components applied in Internet of Things (IoT).