Electrochemical Gelation of Metal Chalcogenide Quantum Dots: Applications in Gas Sensing and Photocatalysis.
Electrochemical Gelation of Metal Chalcogenide Quantum Dots: Applications in Gas Sensing and Photocatalysis.
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金属硫族化合物量子点的电化学掺杂：在气敏和光催化中的应用。
DOI：
10.1021/acs.accounts.3c00042
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发表时间：
2023-05-02
影响因子：
18.3
通讯作者：
Luo, Long
中科院分区：
文献类型：
--
作者：
Geng, Xin;Liu, Daohua;Hewa-Rahinduwage, Chathuranga C.;Brock, Stephanie L.;Luo, Long
金属硫族化物量子点（QD）因其独特的功能特性而受到重视，这些特性与内在（量子限制）和外在（高表面积）效应相关联，如由其尺寸、形状和表面特性所决定的。因此，它们在各种应用中具有相当大的前景，包括能量转换（热电和光电），热电转换和传感。QD凝胶是由互连的QD和孔网络组成的宏观多孔结构，其中孔可以填充有溶剂（即，湿凝胶）或空气（即，气凝胶）。QD凝胶是独特的，因为它们可以制备成宏观尺度的物体，同时完全保留初始QD构建块的尺寸特定的量子限制性质。凝胶的广泛孔隙率还确保凝胶网络中的每个QD可接近周围环境，从而在需要高表面积的应用中实现高性能，例如（光）催化和传感。金属硫属化物QD凝胶常规地通过化学方法制备。我们最近通过开发电化学凝胶化方法扩展了QD凝胶合成的工具箱。相对于传统的化学氧化方法，QD的电化学组装（1）使得能够使用两个额外的杠杆来调节QD组装过程和凝胶结构：电极材料和电势，以及（2）允许在器件基底上直接形成凝胶以简化器件制造并提高再现性。我们已经发现了两种不同的电化学凝胶化方法，每种方法都能够在活性电极表面上直接写入凝胶或形成独立的整料。QD的氧化电凝胶化导致通过二硫属化物（共价）连接体桥接的组装体，而金属介导的电凝胶化经由活性金属电极的电溶解进行以产生通过结合到表面配体（非共价连接体）上的侧链羧酸酯官能团来连接QD的游离离子。我们进一步证明了从共价组装产生的电凝胶组合物可以通过受控的离子交换进行改性，以形成单离子修饰的量子点凝胶，这是一类新的材料。QD凝胶表现出前所未有的NO2气体传感性能和独特的光催化反应性（例如，"氰基舞蹈"异构化和还原性开环芳基化）。在量子点的电化学凝胶化途径及其后修饰的开发过程中揭示的化学对于指导新的纳米颗粒组装策略和基于量子点凝胶的气体传感器和催化剂的设计具有广泛的意义。
Metal chalcogenide quantum dots (QDs) are prized for their unique and functional properties, associated with both intrinsic (quantum confinement) and extrinsic (high surface area) effects, as dictated by their size, shape, and surface characteristics. Thus, they have considerable promise for diverse applications, including energy conversion (thermoelectrics and photovoltaics), photocatalysis, and sensing. QD gels are macroscopic porous structures consisting of interconnected QDs and pore networks in which the pores may be filled with solvent (i.e., wet gels) or air (i.e., aerogels). QD gels are unique because they can be prepared as macroscale objects while fully retaining the size-specific quantum-confined properties of the initial QD building blocks. The extensive porosity of the gels also ensures that each QD in the gel network is accessible to the ambient, leading to high performance in applications that require high surface areas, such as (photo)catalysis and sensing. Metal chalcogenide QD gels are conventionally prepared by chemical approaches. We recently expanded the toolbox for QD gel synthesis by developing electrochemical gelation methods. Relative to conventional chemical oxidation approaches, electrochemical assembly of QDs (1) enables the use of two additional levers for tuning the QD assembly process and gel structure: electrode material and potential, and (2) allows direct gel formation on device substrates to simplify device fabrication and improve reproducibility. We have discovered two distinct electrochemical gelation methods, each of which enables the direct writing of gels on an active electrode surface or the formation of free-standing monoliths. Oxidative electrogelation of QDs leads to assemblies bridged by dichalcogenide (covalent) linkers, whereas metal-mediated electrogelation proceeds via electrodissolution of active metal electrodes to produce free ions that link QDs by binding to pendant carboxylate functionalities on surface ligands (non-covalent linkers). We further demonstrated that the electrogel composition produced from the covalent assembly could be modified by controlled ion exchange to form single-ion decorated bimetallic QD gels, a new category of materials. The QD gels exhibit unprecedented performance for NO2 gas sensing and unique photocatalytic reactivities (e.g., the “cyano dance” isomerization and the reductive ring-opening arylation). The chemistry unveiled during the development of electrochemical gelation pathways for QDs and their post-modification has broad implications for guiding the design of new nanoparticle assembly strategies and QD gel-based gas sensors and catalysts.
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影响因子：
16.6
作者：
Geng X;Li S;Mawella-Vithanage L;Ma T;Kilani M;Wang B;Ma L;Hewa-Rahinduwage CC;Shafikova A;Nikolla E;Mao G;Brock SL;Zhang L;Luo L
通讯作者：
Luo L
影响因子：
8.6
作者：
Gacoin, T;Malier, L;Boilot, JP
通讯作者：
Boilot, JP
影响因子：
15
作者：
Anderson NC;Hendricks MP;Choi JJ;Owen JS
通讯作者：
Owen JS
影响因子：
56.9
作者：
Kovalenko, Maksym V.;Scheele, Marcus;Talapin, Dmitri V.
通讯作者：
Talapin, Dmitri V.
影响因子：
8.6
作者：
Leventis, N;Elder, IA;Merzbacher, CI
通讯作者：
Merzbacher, CI