SnO 2 /CNT nanocomposite supercapacitors fabricated using scanning atmospheric-pressure plasma jets

SnO 2 /CNTelectrodes for supercapacitors are fabricated by first screen-printing pastes containing SnO 2 nanoparticles and CNTs on carbon cloth, following which nitrogen atmospheric pressure plasma jet (APPJ) sintering is performed at various APPJ scan rates. The APPJ scan rates change the time intervals for which the reactive plasma species and the heat of the nitrogen APPJs influence the designated sintering spot on the carbon cloth, resulting in APPJ-sintered SnO 2 /CNTnanocomposites with different properties. The water contact angle decreases with the APPJ scan rate. The improved wettability can facilitate the penetration of the electrolyte into the nanopores of the SnO 2 /CNT nanocomposites, thereby improving the charge storage and specific capacitance of the supercapacitors. Among the three tested APPJ scan rates, 1.5, 3, and 6mms1, the SnO 2 /CNT supercapacitor sintered by APPJ under the lowest APPJ scan rate of 1.5mms1 shows the best specific capacitance of90 F g1 as evaluated by cyclic voltammetry under a potential scan rate of 2mV s1. A high APPJ scan rate may result in low degree of materials activation and sintering, leading to poorer performance of SnO 2 /CNTsupercapacitors. The results suggest the feasibility of an APPJ roll-to-roll process for the fabrication of SnO 2 /CNTnanocomposite supercapacitors.