In this modern era, the necessity of a safe environment with a swift detection of even minute concentrations of hazardous and combustible gases has spurred significance in the advancement of gas sensor technology. In this aspect, the room temperature operable gas sensors have marked their importance by ensuring the safe detection of combustible gases. Nonetheless, the incomplete recovery of such gas sensors requires thermal activation, which entails several limitations. Therefore, the light-activation of gas sensors has garnered considerable attention owing to its compactness and cost-effective operations. The light-activation generates the electron-hole pairs which activate the sensing surface and modulate the charge carrier concentration, thereby enhancing the gas-sensing performances. In this review, the gas-sensing performances of various photoactive sensing materials including metal oxides and two-dimensional materials under light irradiation have been discussed. The gas sensors based on metal oxide and two-dimensional materials have shown significant performance in terms of response, as well as sharp response and recovery times under both ultra-violet and visible light illumination. Finally, this review emphasizes the challenges and future scopes associated with the light-activated room temperature operable gas sensors, which could lead a pathway toward the development of an ultrafast gas sensor.

中文翻译：

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光激活金属氧化物和二维材料气体传感器的研究进展

在当今时代，需要一个安全的环境，能够快速检测甚至微量浓度的危险气体和可燃气体，这对气体传感器技术的进步具有重要意义。在这方面，室温可操作的气体传感器通过确保可燃气体的安全检测而凸显出其重要性。尽管如此，此类气体传感器的不完全恢复需要热激活，这会带来一些限制。因此，光激活气体传感器由于其紧凑性和成本效益的操作而引起了相当大的关注。光激活产生电子空穴对，激活传感表面并调节载流子浓度，从而增强气体传感性能。在这篇综述中，讨论了包括金属氧化物和二维材料在内的各种光敏传感材料在光照射下的气敏性能。基于金属氧化物和二维材料的气体传感器在响应方面表现出显着的性能，并且在紫外光和可见光照射下具有敏锐的响应和恢复时间。最后，本综述强调了与光激活室温可操作气体传感器相关的挑战和未来范围，这可能为超快气体传感器的开发开辟道路。