(2021) Chemical Engineering Journal_Advances in In₂O₃-based materials for the development of hydrogen sulfide sensors

Kumar V., Majhi S.M., Kim K.-H., Kim H.W., Kwon E.E.

(Elsevier B.V.) Chemical Engineering Journal ISSN: 13858947 Vol.404 Issue. Article No.126472 DOI: 10.1016/j.cej.2020.126472

The presence of H2S is an incisive indicator to assess the quality of indoor and/or outdoor air. A number of metal oxide sensors have been developed to measure the concentration levels of H₂S in the environmental systems. Among such sensors, In₂O₃-based sensors are one of the most promising options with the enhanced potential to generate highly sensitive and specific signals in diverse physical/chemical forms (such as pristine, metal-doped/loaded, and composite). Their enhanced sensing performance has been ascribed to many excellent properties (e.g., chemisorption capabilities of oxygen, direct interactions with H₂S, synergetic effect with other materials, generation of sensing signals (at ambient conditions), and capabilities to interact with hydrolyzed form of H₂S). It is also noted that chemoresistive sensing of In₂O₃-materials is a highly preferable option in terms of the strong interactivity with H₂S. Herein, we have reviewed the potential of In₂O₃-based materials (e.g., in pure, metal-doped/loaded, and composite form) for the sensing of H₂S gas with the special emphasis on operation temperature conditions (e.g., at and above room temperature). Discussion is also extended to the H₂S sensing mechanisms and synthesis procedures with the future prospects on this technology. Moreover, a careful evaluation has been made to select the best available option for the In₂O₃-based sensing method based on the evaluation on their performance on parallel basis. © 2020 Elsevier B.V.

We acknowledge support provided by a grant from the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT & Future Planning (Grant No: 2016R1E1A1A01940995 ). VK acknowledges support from the Department of Science and Technology, New Delhi , India in the form of an INSPIRE faculty award and from the Science and Engineering Research Board (SERB) , Government of India under the Early Career Research (ECR) award (File No. ECR/2018/000748).