Identification of lead vacancy defects in lead halide perovskites DOI Creative Commons
D. J. Keeble, Julia Wiktor, Sandeep Pathak

и другие.

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Сен. 22, 2021

Abstract Perovskite photovoltaics advance rapidly, but questions remain regarding point defects: while experiments have detected the presence of electrically active defects no experimentally confirmed microscopic identifications been reported. Here we identify lead monovacancy (V Pb ) in MAPbI 3 (MA = CH NH + using positron annihilation lifetime spectroscopy with aid density functional theory. Experiments on thin film and single crystal samples all exhibited dominant trapping to vacancy defects, a minimum defect ~3 × 10 15 cm −3 was determined. There also evidence at complex $$({{{{{\rm{V}}}}}}_{{{{{\rm{Pb}}}}}}{{{{{\rm{V}}}}}}_{{{{{\rm{I}}}}}})^{-}$$ ( V Pb I ) − minority samples, MA-ion vacancies observed. Our experimental results support predictions other first-principles studies that deep level, hole trapping, $${{{{{{\rm{V}}}}}}}_{{{{{{\rm{Pb}}}}}}}^{2-}$$ 2 , are one most stable . This direct detection identification level native halide perovskite, technologically relevant concentrations, will enable further investigation driven mechanisms.

Язык: Английский

Understanding Defects in Perovskite Solar Cells through Computation: Current Knowledge and Future Challenge DOI Creative Commons
Zhendong Guo,

Man Yuan,

Gaoyuan Chen

и другие.

Advanced Science, Год журнала: 2024, Номер 11(20)

Опубликована: Март 19, 2024

Abstract Lead halide perovskites with superior optoelectrical properties are emerging as a class of excellent materials for applications in solar cells and light‐emitting devices. However, perovskite films often exhibit abundant intrinsic defects, which can limit the efficiency perovskite‐based optoelectronic devices by acting carrier recombination centers. Thus, an understanding defect chemistry lead assumes prominent role further advancing exploitation perovskites, which, to large extent, is performed relying on first‐principles calculations. complex structure, strong anharmonicity, soft lattice pose challenges studies. In this perspective, basis briefly reviewing current knowledge concerning computational studies work concentrates addressing unsolved problems proposing possible research directions future. This perspective particularly emphasizes indispensability developing advanced approaches deeply nature defects conducting data‐driven designing reasonable strategies improve performance applications. Finally, highlights that theoretical should pay more attention establishing close clear links experimental investigations provide useful insights scientific industrial communities.

Язык: Английский

Процитировано

21
Intragrain impurity annihilation for highly efficient and stable perovskite solar cells DOI Creative Commons
Songhua Cai, Zhipeng Li, Yalan Zhang

и другие.

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Март 14, 2024

Intragrain impurities can impart detrimental effects on the efficiency and stability of perovskite solar cells, but they are indiscernible to conventional characterizations thus remain unexplored. Using in situ scanning transmission electron microscopy, we reveal that intragrain impurity nano-clusters inherited from either solution synthesis or post-synthesis storage revert perovskites upon irradiation stimuli, leading counterintuitive amendment crystalline grains. In conjunction with computational modelling, atomically resolve crystallographic transformation modes for annihilation probe their impacts optoelectronic properties. Such critical fundamental findings translated device advancement. Adopting a laser stimulus proven heal nano-clusters, simultaneously boost formamidinium-cesium by virtual improved properties relaxed intra-crystal strain, respectively. This engineering, inspired guided atomic-scale microscopic imaging, presents new prototype cell

Язык: Английский

Процитировано

18
Octahedral units in halide perovskites DOI
Yong Wang, Yu Wang, Tiarnan A. S. Doherty

и другие.

Nature Reviews Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 10, 2025

Язык: Английский

Процитировано

3
Atomic-scale imaging of CH3NH3PbI3 structure and its decomposition pathway DOI Creative Commons
Shulin Chen, Changwei Wu, Bo Han

и другие.

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Сен. 17, 2021

Understanding the atomic structure and structural instability of organic-inorganic hybrid perovskites is key to appreciate their remarkable photoelectric properties failure mechanism. Here, using low-dose imaging technique by direct-detection electron-counting camera in transmission electron microscope, we investigate decomposition pathway CH3NH3PbI3 (MAPbI3) at scale. We successfully image perovskite real space under ultra-low dose condition, observe a two-step process, i.e. initial loss MA followed collapse into 6H-PbI2 with critical threshold also determined. Interestingly, an intermediate phase (MA0.5PbI3) locally ordered vacancies can robustly exist before collapses, enlightening strategies for prevention recovery during degradation. Associated evolution, bandgap gradually increases from ~1.6 eV ~2.1 eV, it found that both C-N N-H bonds be destroyed irradiation, releasing NH3 leaving hydrocarbons. These findings enhance our understanding mechanism MAPbI3, providing potential strategy material optimization.

Язык: Английский

Процитировано

92
Identification of lead vacancy defects in lead halide perovskites DOI Creative Commons
D. J. Keeble, Julia Wiktor, Sandeep Pathak

и другие.

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Сен. 22, 2021

Abstract Perovskite photovoltaics advance rapidly, but questions remain regarding point defects: while experiments have detected the presence of electrically active defects no experimentally confirmed microscopic identifications been reported. Here we identify lead monovacancy (V Pb ) in MAPbI 3 (MA = CH NH + using positron annihilation lifetime spectroscopy with aid density functional theory. Experiments on thin film and single crystal samples all exhibited dominant trapping to vacancy defects, a minimum defect ~3 × 10 15 cm −3 was determined. There also evidence at complex $$({{{{{\rm{V}}}}}}_{{{{{\rm{Pb}}}}}}{{{{{\rm{V}}}}}}_{{{{{\rm{I}}}}}})^{-}$$ ( V Pb I ) − minority samples, MA-ion vacancies observed. Our experimental results support predictions other first-principles studies that deep level, hole trapping, $${{{{{{\rm{V}}}}}}}_{{{{{{\rm{Pb}}}}}}}^{2-}$$ 2 , are one most stable . This direct detection identification level native halide perovskite, technologically relevant concentrations, will enable further investigation driven mechanisms.

Язык: Английский

Процитировано

91