To approach the theoretical efficiency of perovskite solar cells (PSCs), the defects in perovskites should be managed. Among different types of defects, halide vacancies easily form on the surface of perovskite grains (PGs), hindering perovskite stability and the charge-transport process by trapping charge carriers. In this work, oxidized black phosphorus quantum dots (O-BPQDs) are incorporated into a perovskite to resolve these issues. Oxygen atoms of the O-BPQDs interact with uncoordinated Pb (halide vacancies), forming grain interconnections. These interactions reduce halide vacancies and suppress the overall recombination kinetics. Along with defect reduction, the O-BPQDs offer an efficient charge-transport channel across individual PGs. We achieve a best power-conversion efficiency (PCE) of 22.34% for SnO2-based PSCs and of 23.1% for TiO2-based PSCs. These PSCs exhibit moisture stability in a relative humidity (RH) 40% environment comparable to 3D/2D perovskites. Our strategy provides practical applicability and versatility for PSCs to approach the theoretical PCE value.
Bibliographical noteFunding Information:
J.H.P. acknowledges support from the International Energy Joint R&D Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP); the Ministry of Trade, Industry & Energy , Republic of Korea, ( 20208510010310 ); and the NRF under the Ministry of Science and ICT (MSIT), Korea ( NRF-2019R1A2C3010479 , 2018M3D1A1058624 ). J.S. acknowledges financial support from the KETEP from the Ministry of Trade, Industry & Energy ( 20183010014470 ). D.K. acknowledges support from the NRF of Korea grant funded by the Korea government (MSIT) (No. 2020R1A5A1019141 ). J.H.L., T.K., and S. Song contributed equally to this work.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physics and Astronomy(all)