Multifunctional Hydroxylamine‐O‐Sulfonic Acid as Additives for Highly‐Efficient and Stable Perovskite Solar Cells

Abstract

Despite the rapid development of perovskite solar cells (PSCs), defects in the devices continue to impede further improvements in power conversion efficiency (PCE) and operational stability. This work describes the use of hydroxylamine‐O‐sulfonic acid (HOSA) as a bifunctional molecule to enhance the performance of PSCs. Strong coordination between the sulfonic acid group and uncoordinated Pb2+, while the N‐H bond on amino group and uncoordinated I‐ are observed. Thus, due to the synergistic contribution of sulfonic acid group and amino groups, the high‐quality perovskite film with good crystallinity and low defect density is achieved. As a result, the optimal devices exhibit an enhanced efficiency of 23.33%, which is much higher than that of the control device (21.53%). Notably, the optimized target device exhibited excellent long‐term operational stability, retaining over 90% of its initial efficiency after 480 hours at 65 °C, over 93% after a continuous illumination test for 650 hours, and over 96% after nearly 1400 hours of air storage. In contrast, the control device demonstrated poorer stability. These results suggest that selecting a dual‐functional additive is a promising approach to enhance efficiency and maintain stability in PSCs.This article is protected by copyright. All rights reserved.