Oriented inorganic perovskite absorbers processed by colloidal-phase fumigation

Abstract

Inorganic perovskite absorbers are promising candidates for next-generation photovoltaics due to their good thermal and light stabilities. Halide-mixed CsPbI x Br 3−x reach a compromise between its structural tolerance and absorption edge, yet the power conversion efficiencies (PCEs) of the asfabricated cells can be considerably limited by the nonideal quality of solution-processed films. Here we demonstrated a fumigation strategy on colloidal perovskite films using dual-O-donor ethyl acetate (EA). By in-situ monitoring this stage with grazing-incidence wide-angle X-ray scattering technology, we reveal that EA fumigation would impose ripening barrier on colloidal inorganic perovskites and hence slow down the nucleation rate, leading to an intermediate state for processing high-crystallinity and oriented perovskite films with improved photophysical properties. An optimized PCE of 16.6% was finally yielded upon wide-bandgap (1.9 eV) perovskite absorber.

Halide Diffusion Equilibrium and Its Impact on Efficiency Evolution of Perovskite Solar Cells

“…Ideality factor (n) of the devices can be inferred by the slope of V OC as a function of light intensity employed to judge the dominant recombination mechanism [50,51] The values of n were estimated to be 1.43 and 1.22 for the pristine and PEAI-doped devices, indicating the suppressed nonradiative recombination of the PEAI-doped device. [52] Electrochemical impedance spectroscopy was further performed to evaluate carrier kinetics of PSCs. The Nyquist plots of pristine and PEAI-doped devices and the recombination resistance (R rec ) under different bias voltages are depicted in Figure S9a,b in the Supporting Information, respectively.…”

Stabilization Techniques of Lead Halide Perovskite for Photovoltaic Applications

“…A dozen works have shown that the environmental stability of perovskites is closely related to crystallization processes or deposition techniques. [40,[133][134][135] Thermal annealing is a conventional procedure to obtain crystalline materials and is a crucial step in PSCs. It is typically operated under 100-150 C for 10-60 min to obtain high-quality films.…”

Chemical Bath Deposition of NiOx‐NiSO4 Heterostructured Hole Transport Layer for Perovskite Solar Cells

“…[ 5 ] The typical PSCs compose of perovskite absorbers, charge transport materials, and metallic contacts, in which the charge transport materials selectively extract the charge carriers and block the counter charges. [ 6 ] Recent progress in power conversion efficiency (PCE) heavily depended on the advancement of electron transport layers, such as the synthesis of n‐type SnO 2 [ 7 ] or TiO 2 . [ 8 ] In contrast, the inorganic hole transport layers (HTLs) have made very limited success, whose efficiencies were generally lower than that of the organic ones.…”