Tailoring Molecular Space to Navigate Phase Complexity in Cs-Based Quasi-2D Perovskites via Gated-Gaussian-Driven High-Throughput Discovery

Journal Article · Fri Dec 20 00:00:00 EST 2024 · Advanced Energy Materials

DOI:https://doi.org/10.1002/aenm.202404655· OSTI ID:2502176

Um, Minsub ^[1]; Sanchez, Sheryl L. ^[2]; Song, Hochan ^[3]; Lawrie, Benjamin J. ^[4]; Ahn, Hyungju ^[5]; Kalinin, Sergei V. ^[2]; Liu, Yongtao ^[4]; Choi, Hyosung ^[3]; Yang, Jonghee ^[1]; Ahmadi, Mahshid ^[2]

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1. Yonsei Univ., Seoul (Korea, Republic of)
2. Univ. of Tennessee, Knoxville, TN (United States)
3. Hanyang Univ., Seoul (Korea, Republic of)
4. Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States). Center for Nanophase Materials Sciences (CNMS)
5. Pohang Univ. of Science and Technology (POSTECH) (Korea, Republic of). Pohang Accelerator Laboratory

Cesium-based quasi-2D halide perovskites (HPs) offer promising functionalities and low-temperature manufacturability, suited to stable tandem photovoltaics. However, the chemical interplays between the molecular spacers and the inorganic building blocks during crystallization cause substantial phase complexities in the resulting matrices. To successfully optimize and implement the quasi-2D HP functionalities, a systematic understanding of spacer chemistry, along with the seamless navigation of the inherently discrete molecular space, is necessary. Herein, by utilizing high-throughput automated experimentation, the phase complexities in the molecular space of quasi-2D HPs are explored, thus identifying the chemical roles of the spacer cations on the synthesis and functionalities of the complex materials. Furthermore, a novel active machine learning algorithm leveraging a two-stage decision-making process, called gated Gaussian process Bayesian optimization is introduced, to navigate the discrete ternary chemical space defined with two distinctive spacer molecules. Through simultaneous optimization of photoluminescence intensity and stability that “tailors” the chemistry in the molecular space, a ternary-compositional quasi-2D HP film realizing excellent optoelectronic functionalities is demonstrated. Finally, this work not only provides a pathway for the rational and bespoke design of complex HP materials but also sets the stage for accelerated materials discovery in other multifunctional systems.

• Research Organization: Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)
• Grant/Contract Number: AC05-00OR22725
• OSTI ID: 2502176
• Journal Information: Advanced Energy Materials, Journal Name: Advanced Energy Materials Journal Issue: 16 Vol. 15; ISSN 1614-6832
• Publisher: Wiley
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Bayesian optimization
high-throughput automated synthesis
machine learning
phase complexities
quasi-2D perovskites