Iron doped nanocomposites based efficient catalyst for hydrogen production and reduction of organic pollutant

Abstract

Iron doped nanocomposites based effective material were prepared for catalytic reduction of an organic pollutant and hydrogen production. Electrochemical production of hydrogen based on water splitting has been deliberated as an auspicious approach, however, the lethargic anodic oxygen evolution reaction (OER) restricts the effectiveness of water splitting. Also, active catalysts for catalytic reduction of organic pollutants are also highly required for the catalytic removal of organic pollutants. Therefore, in this manuscript, we report iron doped metal oxide nanocomposites (Fe2O3-ZnO and Fe-SnO2) as multifunctional catalysts for OER, hydrogen evolution reaction (HER) as well as catalytic reduction of organic pollutants. Therefore, efficient nano-catalyst based on iron oxide doped tin oxides and iron doped zinc oxide with long-term stability and efficient hydrogen generation and removal of organic pollutants has been developed. The catalytic efficiency of the developed materials was evaluated toward producing hydrogen and removing organic pollutants. In HER, it was found that Fe2O3-ZnO and Fe-SnO2 needs a low over potential to produce 10 mA cm−2 in 0.5 M KOH and 0.5 M H2SO4. Similarly, in OER, 600 mV is needed to drive the current density of 20 mA cm−2 in 1.0 M KOH using Fe2O3-ZnO. Fe2O3-ZnO illustrates lower Tafel slopes of 64.3 mV dec-1 and 96.0 mV dec-1 in HER using 0.5 M KOH and 0.5 M H2SO4, respectively, while in OER, the Tafel slope is 76.5 mV dec-1 using 1.0 M KOH. The catalytic efficiency of Fe2O3-ZnO and Fe-SnO2 was also evaluated for the removal of 4-nitrophenol and among them, Fe-SnO2 displayed good catalytic efficiency toward 4-nitrophenol reduction. 4-Nitrophenol was totally reduced in less than 5 min using Fe-SnO2 as a catalyst.