Extending the Defect Tolerance of Halide Perovskite Nanocrystals to Hot Carrier Cooling Dynamics

• DOI: 10.48550/arxiv.2404.06276
• Publication Date: 2024-04-09
• Authors: Junzhi Ye; Navendu Mondal; Ben P. Carwithen; Yunwei Zhang; Linjie Dai; Xiangbin Fan; Jian Mao; Zhiqiang Cui; Pratyush Ghosh; Clara Otero‐Martínez; Lars van Turnhout; Zhongzheng Yu; Ziming Chen; Neil C. Greenham; Samuel D. Stranks; Lakshminarayana P...; Artem A. Bakulin; Akshay Rao; Robert L. Z. Hoye
• Keywords: Dynamics

Defect tolerance is a critical enabling factor for efficient lead-halide perovskite materials, but the current understanding primarily on band-edge (cold) carriers, with significant debate over whether hot carriers (HCs) can also exhibit defect tolerance. Here, this important gap in field addressed by investigating how internationally-introduced traps affect HC relaxation CsPbX3 nanocrystals (X = Br, I, or mixture). Using femtosecond interband and intraband spectroscopy, along energy-dependent photoluminescence measurements kinetic modelling, it found that HCs are not universally tolerant CsPbX3, strongly correlated to of cold requiring shallow be present (as CsPbI3). It directly captured traps, instead going through an intermediate carrier, deeper cause faster cooling, reducing effects phonon bottleneck Auger reheating. This work provides insights into defects influence HCs, which will designing materials carrier solar cells, multiexciton generation, optical gain media.