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arXiv · 1508.07436

Influence of in-plane and bridging oxygen vacancies of SnO_2 nanostructures on CH_4 sensing at low operating temperatures

Venkataramana Bonu·A. Das·Arun K Prasad·Nanda Gopala Krishna·Sandip Dhara·A. K. Tyagi
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Abstract

Role of 'O' defects in sensing pollutant with nanostructured SnO_2 is not well understood, especially at low temperatures. SnO_2 nanoparticles were grown by soft chemistry route followed by subsequent annealing treatment under specific conditions. Nanowires were grown by chemical vapor deposition technique. A systematic photoluminescence (PL) investigation of 'O' defects in SnO_2 nanostructures revealed a strong correlation between shallow donors created by the in-plane and the bridging 'O' vacancies and gas sensing at low temperatures. These SnO_2 nanostructures detected methane (CH_4), a reducing and green house gas at a low temperature of 50 ^oC. Response of CH_4 was found to be strongly dependent on surface defect in comparison to surface to volume ratio. Control over 'O' vacancies during the synthesis of SnO2 nanomaterials, as supported by X-ray photoelectron spectroscopy and subsequent elucidation for low temperature sensing are demonstrated.

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Venkataramana Bonu, A. Das, Arun K Prasad, Nanda Gopala Krishna, Sandip Dhara, A. K. Tyagi. 2015-08-29. Influence of in-plane and bridging oxygen vacancies of SnO_2 nanostructures on CH_4 sensing at low operating temperatures. https://doi.org/10.1063/1.4904457

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