多酸/半导体串联异质结的构建及其气敏性能研究

Semiconductor materials have been one of the cores of gas sensors because of high sensitivity and easy operation. As a low-cost material, inorganic semiconductor needs to be developed. However, high carrier recombination rate exists in ratehomogenous material, which limits the gas sensing performance. As a type of inorganic metal-oxo cluster framework compounds, polyoxometalates (POMs) have diverse structures and fine physicochemical properties. What’s more, the energy band of POMs is similar to that of semiconductors. POMs can be used as an efficient electron acceptor, which could capture the electrons from conduction band of semiconductors and thus retard the electron–hole recombination. However, the properties of POMs/semiconductor tandem heterojunctions have rarely been explored so far. This project focuses on the research of the design and preparation of unidimensional semiconductor/POMs/semiconductor nanofiber. The nanofiber contains a core-shell structure with three stratified layers, forming two tandem heterojunctions. The gas sensing performance and the relationship of the composition and structure with the gas sensing performance will be studied. These research findings will provide theoretical basis and guidance for the development of POMs-based gas sensors.

半导体材料是气体传感器的核心之一，灵敏度高，操作简单。实现低成本、高性能气敏材料的实际应用，急需新型半导体材料的发展。然而单一组分半导体材料存在着很高的载流子复合率，限制了气敏材料的性能。多金属氧酸盐是一类骨架结构中含有钨、钼等过渡元素的无机多金属氧簇化合物，结构多样，物理化学性质优异，其能带结构与金属半导体类似。多酸还是良好的电子接受体，可以有效促进半导体材料中载流子的迁移。然而，有关多酸/半导体串联异质结材料的研究还未见报导。本项目拟采用同轴静电纺丝技术，制备一维的半导体/多酸/半导体复合纳米纤维材料，阐明其形成机理。该材料具有三层明显分层的同轴核壳结构，在三层之间形成两个串联的异质结。研究此类纳米纤维的气体传感性能，并探索不同结构的多酸与气体传感性能的构效关系，提出传感作用机理。这些研究结果对发展多酸在气体传感领域中的实际应用具有重要的理论和实际意义。

半导体材料是气体传感器的核心之一，灵敏度高，操作简单。实现低成本、高性能气敏材料的实际应用，急需新型半导体材料的发展。然而单一组分半导体材料存在着很高的载流子复合率，限制了气敏材料的性能。多金属氧酸盐是一类骨架结构中含有钨、钼等过渡元素的无机多金属氧簇化合物，结构多样，物理化学性质优异，其能带结构与金属半导体类似。多酸还是良好的电子接受体，可以有效促进半导体材料中载流子的迁移。然而，有关多酸/半导体串联异质结材料的研究还未见报导。本项目采用同轴静电纺丝技术，制备多种一维的半导体/多酸/半导体复合纳米纤维材料，并阐明其形成机理。该类材料具有三层明显分层的同轴核壳结构，在三层之间形成两个串联的异质结。此外，深入研究了此类纳米纤维的气体传感性能，并探索不同类型的多酸与气体传感性能的构效关系，提出了传感作用机理。这些研究结果对发展多酸在气体传感领域中的实际应用具有重要的理论和实际意义。