%0 Journal Article
%A Ji, Sang-Geun
%A Noh, Eunseo
%A Kim, Jongbeom
%A Duan, Weiyuan
%A Kang, Bong Joo
%A Lee, Yonghui
%A Ding, Kaining
%A Seok, Sang Il
%T Cooperative Dipole Engineering Unlocks 92.8% Shockley–Queisser Voltage Limit in Wide-Bandgap Perovskites for Tandem Photovoltaics
%J ACS energy letters
%V 11
%N 1
%@ 2380-8195
%C Washington, DC
%I American Chemical Society
%M FZJ-2026-01212
%P 442 - 450
%D 2026
%X Wide-bandgap (WBG) perovskite solar cells (PSCs, Eg ≃ 1.67 eV) still suffer from pronounced open-circuit-voltage (VOC) deficits. Here, we report a synergistic surface-passivation strategy that coassembles a dipolar quaternary-ammonium salt, acetylcholine chloride (ACCl), with an electron-rich long-chain alkylammonium halide, n-octylammonium iodide (OAI). A mixed ACCl:OAI treatment reconstructs the perovskite surface, lowers surface-trap density, and aligns the valence band with the hole-transport layer. Consequently, the champion WBG PSC delivers VOC = 1.29 V, JSC = 20.0 mA cm–2, FF = 82.8%, and PCE = 21.27%, corresponding to 92.8% of the Shockley–Queisser voltage limit. When integrated as the top absorber in a monolithic n-i-p perovskite/p-type Si tandem, the passivated WBG cell contributed to a PCE of 26.8% with a VOC of 1.91 V. These results reveal that cooperative defect passivation and energy-level engineering are both essential to unlock the full voltage potential of WBG perovskites.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:001644774500001
%R 10.1021/acsenergylett.5c02738
%U https://juser.fz-juelich.de/record/1052856