Atmospheric-pressure-plasma-jet sintered nanoporous SnO2

We apply atmospheric pressure plasma jets (APPJs) for the rapid sintering of nanoporous SnO2. The influence of the APPJ sintering duration on the properties of nanoporous SnO2 is investigated. With an increase in the APPJ sintering time, slope of optical absorption edge decreases and then increases, optical bandgap decreases and then increases, the electrical conductivity increases and then decreases, and activation energy of electrical conductivity decreases and then increases. A proper APPJ-sintering time is recommended for optimal performance of sintered SnO2 and prolonged APPJ-sintering may deteriorate the material performance. This sequential screen-printing and APPJ sintering process is scalable and can potentially be used for a roll-to-roll process, in which screen-printing is extensively used for the second and follow-up layers owing to the alignment requirements. APPJ sintered nanoporous SnO2 with high surface-to-volume ratio is a potential candidate material for gas sensors or catalysts, in which large surface reactive sites are demanded.