Easily Attainable, Efficient Solar Cell with Mass Yield of Nanorod Single-Crystalline Organo-Metal Halide Perovskite Based on a Ball Milling Technique

摘要

Generally, nanoparticles of CH3NH3PbI3 (MLI) powders are increasingly recognized for their applications in solar cells. In this article, a new substitutional path to efficient mass yield with crucial reaction rates was proposed for the synthesis of MLI using a ball milling technique. We compare between the condensation reflux strategy (RM) and the ball milling (BM) technique as synthetic routes to produce microparticles (RM-MLI) and nanoparticles (BMMLI) from MLI microcrystalline powder. The change in crystal structures, microstructure, and optical characteristics was investigated using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and photoluminescence emission (PL). FESEM micrographs showed a plummet straight down in particle size from 10 μm to ～30 nm. The nanorods morphology was elucidated with transmission electron microscope (TEM). Optical absorption measurements indicate that compounds behaved with the characteristic of direct band gap with Eg recorded at 1.50 and 1.56 eV for RM-MLI and BM-MLI, respectively. The two samples exhibited an intense near-IR photoluminescence (PL) emission in the 700-800 nm range at room temperature. The Hall effect was displayed as p-type semiconductors resulting from the positive sign of the Hall coefficient. Typically, with Cu2ZnSnS4 (CZTS) as a hole transport material, the perovskite-sensitized TiO2 film showed power conversion efficiencies (PCE) of 7.33 and 9.63% with fill factor records of 0.61 and 0.66 for RM-MLI and BM-MLI, respectively. Meanwhile, the results gave a maximum external quantum efficiency (EQE) of 65% at 530 nm at AM 1.5G 1 sun intensity (100 mW cm2). Overall, this work gives an exceptionally simple, efficient methodology to synthesize MLI nanoparticles with efficient power conversion.