LAUSR

Abstract The interesting and multifunctional properties of alpha -manganese dioxide ( α -MnO 2 ) are considered to be highly sensitive and selective to nitrogen dioxide (NO 2 ) chemresistive gas sensors. The α -MnO 2 mesoporous interlocked micro-cubes composed of several interconnected nanocrystals synthesized by a facile and low-cost hydrothermal method on soda-lime glass substrate are envisaged as selective and sensitive NO 2 gas sensors. Phase-purity and surface area with pore-size distribution are initially screened. The three-dimensional α -MnO 2 mesoporous-cube-based gas sensors tested for NO 2 gas from room-temperature (27 °C) to 250 °C have demonstrated 33% response for 100 ppm NO 2 levels at 150 °C. The response and recovery time values of the α -MnO 2 sensor are found to be 26 s and recovery 91 s, respectively, with high selectivity, good sensitivity, and considerable chemical and environmental stabilities, confirming the gas sensor applications potentiality of α -MnO 2 morphology which is a combination of interlocked mesoporous micro-cubes and well-connected nanocrystals.