Vincent Obiozo Eze

High-performance CH3NH3PbI3 perovskite solar cells fabricated under ambient conditions with high relative humidity

Hygroscopic perovskite solar cells are commonly fabricated under conditions of inert atmosphere or low relative humidity (RH). To generate high-performance perovskite light-absorbing layers for super power conversion efficiency (PCE), we fabricated CH3NH3PbI3 solar cells under ambient conditions (RH = 42–48%) by a flowing gas directly from high-RH air. The primary advantage of this technique, together with the casting of a hot solution and quick conduction, enabled us to achieve the highest and average PCEs of 16.32 and 14.27% respectively, with an extremely small deviation of 0.49%. Our research will be of significance for fabricating highly efficient and reproducible perovskite photovoltaics.

Air-assisted flow and two-step spin-coating for highly efficient CH3NH3PbI3 perovskite solar cells

There is a multitude of reports on different methods of fabricating organic–inorganic halide perovskite films for high-efficiency solar cells. In this study, planar heterojunction (PHJ) CH3NH3PbI3 perovskite solar cells were prepared by the two-step spin-coating method. The uniformity of the perovskite light-absorbing layer is enhanced by air-assisted flow (AAF). We compared the photovoltaic performance characteristics of films prepared with and without AAF. Perovskite solar cells constructed without AAF showed a power conversion efficiency (PCE) of 8.67%, whereas a higher PCE of 13.28% was obtained with an AAF-based perovskite solar cell. Our study presents a useful technique for preparing high-quality perovskite films.

Enhanced photovoltaic performance of planar perovskite solar cells fabricated in ambient air by solvent annealing treatment method

In this paper, we report on planar perovskite solar cells (PSCs) fabricated by a simple one-step solution process and an antisolvent bath (ASB) method in ambient air. The ASB method enabled the efficient extraction of the precursor solvent and induced the swift crystallization of uniform and highly smooth perovskite films with an average grain size of about 0.34 µm. The morphology and grain growth of the resultant perovskite film were further improved by solvent annealing (SA) under dimethyl sulfoxide (DMSO) vapor atmosphere at 150 °C for 10 min and thus an average power conversion efficiency (PCE) of 15.20% and a maximum efficiency of 16.77% were achieved. This work highlights the importance of solvent annealing for perovskite prepared by a one-step solution process and an ASB method, and offers a facile and attractive way to fabricate high-performance perovskite solar cells.