Self-assembled TiO_(2)hole-blocking layers for efficient perovskite solar cells

The self-assembly process for compatible functional layers of devices is a simple,feasible,and energy-saving strategy.In mesoporous perovskite solar cells(PSCs),compact and scaffold TiO_(2) films generally function as the hole-blocking and electron-transporting layers,respectively.However,both of these layers are usually generated through a high-temperature annealing process.Here,we deposited TiO_(2) compact films through a room-temperature self-assembly process as effective hole-blocking layers for PSCs.The thickness of TiO_(2) compact films can be easily controlled by the deposition time.Through the optimization of TiO_(2) compact films(80 nm),the power conversion efficiency(PCE)of mesoporous PSCs without and with hole conductor layers increases up to 10.66%and 17.95%,respectively.Notably,an all-low-temperature planar PSC with the self-assembled TiO_(2) layer exhibits a PCE of 16.41%.