Electrochemical and Microstructural Investigations of PtFe Nanocompounds Synthesized by Atmospheric-Pressure Plasma Jet

Abstract

© The Author(s) 2019. Published by ECS. A nitrogen DC-pulse atmosphere pressure plasma jet (APPJ) is used to convert ferric nitrate (Fe(NO3)3) and chloroplatinic acid (H2PtCl6) mixed liquid precursor films into PtFe nanocompounds on a fluorine-doped tin oxide (FTO) substrate. Scanning transmission electron microscopy indicates nanoparticles distributed on a thin continuous layer on the FTO substrate. The APPJ-synthesized PtFe nanocompounds contain a mixture of crystalline and amorphous phases. X-ray photoelectron spectroscopy shows that most Pt is in the metallic phase and most Fe, in the oxidized phase. A dye-sensitized solar cell (DSSC) with only 5-s APPJ-processed PtFe counter electrode (CE) shows significantly improved efficiency. This suggests the rapid processing capability of the nitrogen DC-pulse APPJ. A PtFe prepared with higher H2PtCl6/Fe(NO3)3 volume ratio shows better catalytic performance, as confirmed by cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel experiments. The DSSC with APPJ-processed PtFe CE shows comparable efficiency to that of 15-min furnace-calcined Pt CE, suggesting that the APPJ processed PtFe requires less Pt.