Enhanced performance of CH3NH3PbI3−x Cl x perovskite solar cells by CH3NH3I modification of TiO2-perovskite layer interface

• DOI: 10.1186/s11671-016-1540-4
• Publication Date: 2016-06-29T19:58:42Z
• Authors: Wen Wang; Zongbao Zhang; Yangyang Cai; Jinshan Chen; Jianming Wang; Riyan Huang; Xubing Lu; Xingsen Gao; Lingling Shui; Sujuan Wu; Jun-Ming Liu
• Keywords: Materials Science(all); Nano Express; 02 engineering and technology; Condensed Matter Physics; 0210 nano-technology; 7. Clean energy

In this work, perovskite solar cells (PSCs) with CH3NH3PbI3-x Cl x as active layer and spiro-OMeTAD hole-transport media have been fabricated by one-step method. The methylammonium iodide (CH3NH3I) solution different concentrations is used to modify the interface between mesoporous TiO2 (meso-TiO2) film layer. Several techniques including X-ray diffraction, scanning electron microscopy, optical absorption, electrochemical impedance spectroscopy (EIS) photoluminescence are investigate effect of interfacial modification. It found that modification CH3NH3I enhance crystallinity increase grain size layer, improve surface wetting properties precursor on meso-TiO2 film. sunlight absorption external quantum efficiency PSCs in visible region wavelength less than 600 nm improved. Nyquist plots obtained from EIS suggest can reduce charge recombination rates. measurement shows exciton dissociation modified devices more effective control samples. photovoltaic performance be significantly improved respect reference (control) devices. at optimized concentration demonstrate average power conversion 12.27 % comparison 9.68 for