LAUSR

In the present article, the electron transport materials titanium oxide (TiO2), bathocuproine (BCP) and phenyl-C61-butyric acid methyl ester (PCBM) were synthesized and investigated for the application in methylammonium lead bromide (CH3NH3PbBr3) perovskite photodetectors. Results show that device based on TiO2 electron transport layer (ETL) shows higher photocurrent, responsivity and detectivity as compared to the devices based on BCP and PCBM ETL. However, ideality factor, charge carrier mobility, trap width and trap density were found to be comparable for the devices composed of BCP ETL and TiO2 ETL. The TiO2 ETL might help in the passivation of interface traps, form good quality intimate interfaces and offers more appropriate energy levels for effective blocking of holes and efficient extraction of electrons, resulting in the improved device performance. Through impedance spectroscopy analysis, the superior performance of the device with TiO2 ETL can be attributed to the better contact selectivity and high recombination resistance.