Kaur Navpreet, Singh Mandeep, Comini Elisabetta
Sensor Laboratory, University of Brescia, Via D. Valotti 9, 25133 Brescia, Italy.
Langmuir. 2020 Jun 16;36(23):6326-6344. doi: 10.1021/acs.langmuir.0c00701. Epub 2020 Jun 7.
Day by day, the demand for portable, low cost, and efficient chemical/gas-sensing devices is increasing due to worldwide industrial growth for various purposes such as environmental monitoring and health care. To fulfill this demand, nanostructured metal oxides can be used as active materials for chemical/gas sensors due to their high crystallinity, remarkable physical/chemical properties, ease of synthesis, and low cost. In particular, (1D) one-dimensional metal oxides nanostructures, such as nanowires, exhibit a fast response, selectivity, and stability due to their high surface-to-volume ratio, well-defined crystal orientations, controlled unidirectional electrical properties, and self-heating phenomenon. Moreover, with the availability of large-scale production methods for nanowire growth such as thermal oxidation and evaporation-condensation growth, the development of highly efficient, low cost, portable, and stable chemical sensing devices is possible. In the last two decades, tremendous advances have been achieved in 1D nanostructured gas sensors ever since the pioneering work by Comini on the development of a SnO nanobelt for gas sensor applications in 2002, which is one such example from which many researchers began to explore the field of 1D-nanostructure-based chemical/gas sensors. The Sensor Laboratory (University of Brescia) has made major contributions to the field of metal oxide nanowire chemical/gas-sensing devices. Over the years, different metal oxides such as SnO, ZnO, WO, NiO, CuO, and their heterostructures have been grown for their nanowire morphology and successfully integrated into chemoresistive gas-sensing devices. Hence in this invited feature article, Sensor Laboratory research on the synthesis of metal oxide nanowires and novel heterostructures and their characterization and gas-sensing performance during exposure to different gas analytes has been presented. Moreover, some new strategies such as branched-like nanowire heterostructures and core-shell nanowire structures adopted to enhance the performance of nanowire-based chemical sensor are presented in detail.
由于全球范围内出于环境监测和医疗保健等各种目的的工业增长，对便携式、低成本且高效的化学/气体传感设备的需求与日俱增。为满足这一需求，纳米结构金属氧化物因其高结晶度、卓越的物理/化学性质、易于合成且成本低廉，可被用作化学/气体传感器的活性材料。特别是一维金属氧化物纳米结构，如纳米线，由于其高的表面积与体积比、明确的晶体取向、可控的单向电学性质以及自热现象，展现出快速响应、选择性和稳定性。此外，随着诸如热氧化和蒸发-冷凝生长等大规模纳米线生长方法的出现，开发高效、低成本、便携式且稳定的化学传感设备成为可能。在过去二十年中，自2002年Comini开创性地开发用于气体传感器应用的SnO纳米带以来，一维纳米结构气体传感器取得了巨大进展，这是众多研究人员开始探索基于一维纳米结构的化学/气体传感器领域的一个例子。布雷西亚大学传感器实验室在金属氧化物纳米线化学/气体传感设备领域做出了重大贡献。多年来，不同的金属氧化物如SnO、ZnO、WO、NiO、CuO及其异质结构已被生长成纳米线形态，并成功集成到化学电阻式气体传感设备中。因此，在这篇特邀专题文章中，介绍了传感器实验室对金属氧化物纳米线和新型异质结构的合成及其在暴露于不同气体分析物时的表征和气体传感性能的研究。此外，还详细介绍了一些用于提高基于纳米线的化学传感器性能的新策略，如分支状纳米线异质结构和核壳纳米线结构。
