Multidentate Chelation Achieves Bilateral Passivation toward Efficient and Stable Perovskite Solar Cells with Minimized Energy Losses

Haichao Yang; Ru Li; Shaokuan Gong; Huaxin Wang; Saif M H Qaid; Qian Zhou; Wensi Cai; Xihan Chen; Jiangzhao Chen; Zhigang Zang

doi:10.1021/acs.nanolett.3c02444

Multidentate Chelation Achieves Bilateral Passivation toward Efficient and Stable Perovskite Solar Cells with Minimized Energy Losses

Nano Lett. 2023 Sep 27;23(18):8610-8619. doi: 10.1021/acs.nanolett.3c02444. Epub 2023 Sep 6.

Authors

Affiliations

¹ Key Laboratory of Optoelectronic Technology & Systems (Ministry of Education), Chongqing University, Chongqing 400044, China.
² SUSTech Energy Institute for Carbon Neutrality, Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen, Guangdong 518055, China.
³ Department of Physics & Astronomy, College of Sciences, King Saud University, P.O. Box 2455, Riyadh 11451, Saudi Arabia.

PMID: 37671796
DOI: 10.1021/acs.nanolett.3c02444

Abstract

Defects in the electron transport layer (ETL), perovskite, and buried interface will result in considerable nonradiative recombination. Here, a bottom-up bilateral modification strategy is proposed by incorporating arsenazo III (AA), a chromogenic agent for metal ions, to regulate SnO₂ nanoparticles. AA can complex with uncoordinated Sn⁴⁺/Pb²⁺ in the form of multidentate chelation. Furthermore, by forming a hydrogen bond with formamidinium (FA), AA can suppress FA⁺ defects and regulate crystallization. Multiple chemical bonds between AA and functional layers are established, synergistically preventing the agglomeration of SnO₂ nanoparticles, enhancing carrier transport dynamics, passivating bilateral defects, releasing tensile stress, and promoting the crystallization of perovskite. Ultimately, the AA-optimized power conversion efficiency (PCE) of the methylammonium-free (MA-free) devices (Rb_0.02(FA_0.95Cs_0.05)_0.98PbI_2.91Br_0.03Cl_0.06) is boosted from 20.88% to 23.17% with a high open-circuit voltage (V_OC) exceeding 1.18 V and ultralow energy losses down to 0.37 eV. In addition, the optimized devices also exhibit superior stability.

Keywords: SnO2 nanoparticles; bilateral passivation; minimized energy losses; multidentate chelation; perovskite solar cells; synergistic effects; tensile stress releasing.