Electrochemical Spectroscopy: Evaluation and determination of Carbon dioxide reduction based on tin oxide doped ethyl cellulose as electrocatalyst by H-type cell and reversible hydrogen electrode

Electrocatalytic Carbon dioxide (CO2) reduction to carbon products on SnO2-doped ethyl cellulose (EC) was prepared by dispersion of nano-sized tin oxide (SnO2, 25 nm) in ethyl cellulose through sonication by an ultrasonic probe (600 W) for 60 min. The SnO2-EC catalyst is characterized by field emission scanning electron microscopy (FESEM), atomic force microscopy (AFM), and X-ray diffraction (XRD). The electrocatalytic performance for CO2 reduction was investigated by loading SnO2-EC paste on a 306S.S. rotated disc. The CO2 electroreduction occurred in an H-type cell with three electrodes in 0.1M KHCO3 saturated with CO2 at different potential ranges of -1.0 V to -1.8V vs. RHE for 3 hours. The oxygen content of liquid products was collected and determined using a chemical oxygen demand (COD,15–300 mg L-1) kit, which was quantified by a colorimeter. A higher oxygen content concentration was obtained at -1.2V vs. RHE (-2 mA cm-2) and found to be 235 mg L-1, while the oxygen content tends to decrease with a more negative applied potential of -1.4V, -1.6V, and 1.8V vs. RHE with current densities of -2.5 mA cm-2, -7.3 mA cm-2, and -15.6 mA cm-2, respectively.