Evolution of Hollow CuInS2 Nanododecahedrons via Kirkendall Effect Driven by Cation Exchange for Efficient Solar Water Splitting
Evolution of Hollow CuInS2 Nanododecahedrons via Kirkendall Effect Driven by Cation Exchange for Efficient Solar Water Splitting
复制标题
阳离子交换驱动的柯肯德尔效应中空 CuInS2 纳米十二面体的演化，实现高效太阳能水分解
DOI：
10.1021/acsami.9b05325
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发表时间：
2019
影响因子：
9.5
通讯作者：
Zhang Jiatao
中科院分区：
文献类型：
--
作者：
Li Yuemei;Liu Jia;Li Xinyuan;Wan Xiaodong;Pan Rongrong;Rong Hongpan;Liu Jiajia;Chen Wenxing;Zhang Jiatao
中空结构的半导体纳米晶体（NC）由于其引人注目的结构相关性质而引起了巨大的研究兴趣，这些性质可以促进包括太阳能水分解在内的许多重要应用的发展。然而，由于难以平衡多种前体的反应性，具有中空结构的多组分半导体NC（如I-III-VI 2和I2-II-IV-VI 4半导体）的产生仍然是一个巨大的挑战。在这项研究中，我们报告了一种有效的策略，制备空心CuInS 2纳米十二面体具有高度均匀的形貌和成分，基于Kirkendall效应驱动的Cu+和In 3+之间的阳离子交换使用Cu 2-xS纳米十二面体作为模板。阳离子的扩散速率不相等导致空位沿Cu 2-xS十二面体的（0 16 0）面沿着向内流动，形成了在核区具有条纹状空位的Cu 2-xS@CuInS2核壳中间体.光吸收研究和光电化学测量表明，空心化程度的增加有利于增强光捕获和光生电荷载流子的分离。结果表明，所制备的空心CuInS 2纳米十二面体具有较高的光催化析氢活性，比以往报道的不同结构的CuInS 2光催化剂有上级的性能.我们设想，Cu 2-xS NC模板可获得的多种形态和Cu+用于阳离子交换的优点可以使该方法适用于各种各样的先前难以处理的结构和组合物。
Hollow-structured semiconductor nanocrystals (NCs) have aroused tremendous research interest because of their compelling structure-related properties that can facilitate the development of many important applications including solar water splitting. However, the creation of multicomponent semiconductor NCs (such as I–III–VI2and I2–II–IV–VI4semiconductors) possessing a hollow architecture still remains a great challenge because of the difficulty in balancing the reactivities of multiple precursors. In this study, we report an effective strategy to prepare hollow CuInS2nanododecahedrons featuring high uniformity in morphology and composition, based on the Kirkendall effect driven by the cation exchange between Cu+and In3+using Cu2–xS nanododecahedrons as templates. The unequal diffusion rates of cations result in an inward flux of vacancies favorably along the (0 16 0) facets of Cu2–xS dodecahedrons, forming a Cu2–xS@CuInS2core–shell intermediate with striped voids in the core region. Optical absorption studies and photoelectrochemical measurements imply that the increase in the hollowing degree of the NCs benefits enhanced light harvesting and separation of photogenerated charge carriers. As a result, the obtained hollow CuInS2nanododecahedrons present a high activity in photocatalytic hydrogen evolution, much superior to previously reported CuInS2photocatalysts with different architectures. We envision that the multifarious morphologies attainable for the Cu2–xS NC templates and the advantages of Cu+for cation exchange can make this method adaptable to a vast variety of previously intractable structures and compositions.