Fluoride Doping in Crystalline and Amorphous Indium Oxide Semiconductors
Fluoride Doping in Crystalline and Amorphous Indium Oxide Semiconductors
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晶态和非晶态氧化铟半导体中的氟化物掺杂
DOI：
10.1021/acs.chemmater.2c00053
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发表时间：
2022-03
影响因子：
8.6
通讯作者：
Aritra Sil;Michael J. Deck;Elise A. Goldfine;Chi Zhang;Sawankumar V. Patel;Steven Flynn;Haoyu Liu
中科院分区：
文献类型：
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作者：
Aritra Sil;Michael J. Deck;Elise A. Goldfine;Chi Zhang;Sawankumar V. Patel;Steven Flynn;Haoyu Liu
在这篇文章中，我们用实验和理论两种方法研究了晶体和非晶体氧化铟中氟化物掺杂的结构和电子效应。原始的结晶和非晶的氟化铀掺杂氧化铟（F：In − O）相分别通过基于溶液的燃烧合成和溶胶-凝胶技术制备。这些材料的化学组成、环境和固态微观结构用各种最先进的技术进行了广泛的研究，如紫外-维斯、X射线光电子能谱、掠入射X射线衍射、19 F和115 In固态NMR、高分辨率透射电子显微镜（HR-TEM）、和扩展X射线吸收精细结构（EXAFS）以及密度泛函理论（DFT）计算结合MD模拟。有趣的是，紫外维斯数据显示，虽然晶相中F-掺杂后带隙增加，但非晶相中带隙减少。19 F固态NMR数据表明，在氟化后，InO 3 F3环境占主导地位的结晶氧化物相，而InO 4 F2环境是占主导地位的非晶氧化物相。HR-TEM数据表明，氟化物掺杂抑制了结晶和非晶In − O相的结晶，这一结果得到了115 In固态NMR、EXAFS和DFT-MD模拟数据的支持。因此，本研究建立了所有MD模拟都是在NVT系综中使用Nose-Hoover恒温器进行的，积分时间步长为2 fs。为了对模拟的非晶氧化物进行精确的结构分析（对相关函数以及距离和角度分布），使用了室温In − O和F：In − O结构。在DFT中使用PBE泛函分析In-[O，F]配位，对从头算MD模拟得到的原子构型进行了优化。
: In this contribution, the structural and electronic e ff ects of fl uoride doping in both crystalline and amorphous indium oxides are investigated by both experimental and theoretical techniques. Pristine crystalline and amorphous fl uoride-doped indium oxide (F:In − O) phases were prepared by solution-based combustion synthesis and sol − gel techniques, respectively. The chemical composition, environment, and solid-state microstructure of these materials were extensively studied with a wide array of state-of-the-art techniques such as UV − vis, X-ray photoelectron spectroscopy, grazing incidence X-ray di ff raction, 19 F and 115 In solid-state NMR, high-resolution transmission electron microscopy (HR-TEM), and extended X-ray absorption fi ne structure (EXAFS) as well as by density functional theory (DFT) computation combined with MD simulations. Interestingly, the UV − vis data reveal that while the band gap increases upon F − -doping in the crystalline phase, it decreases in the amorphous phase. The 19 F solid-state NMR data indicate that upon fl uorination, the InO 3 F 3 environment predominates in the crystalline oxide phase, whereas the InO 4 F 2 environment is predominant in the amorphous oxide phase. The HR-TEM data indicate that fl uoride doping inhibits crystallization in both crystalline and amorphous In − O phases, a result supported by the 115 In solid-state NMR, EXAFS, and DFT-MD simulation data. Thus, this study establishes fl All MD simulations were carried out in the NVT ensemble with the Nose − Hoover thermostat using an integration time step of 2 fs. For an accurate structural analysis of the simulated amorphous oxides (pair correlation function as well as distance and angle distributions), the room-temperature In − O and F:In − O structures were used. The atomic con fi gurations obtained from the ab initio MD simulations were optimized within DFT using the PBE functional to analyze the In-[O,F] coordination.