Synthesis of Different Pt‐ZnO Binary Composites for Synergistic Photo‐Electrocatalytic Oxidation of Methanol in Alkali

Abstract

Various compositions of Pt-ZnO binary nano composites are synthesized as anode-catalyst for methanol oxidation reaction (MOR) in alkali under both presence and absence of visible light. Synthesized materials are characterised by various microscopic and spectroscopic techniques. The catalytic capabilities of synthesized anodes are evaluated by cyclic voltametry (CV), chronoamperometry (CA) and electro-chemical impedance spectroscopy (EIS). CV studies indicate that Pt-ZnO composite containing 0.6 wt % of Pt displays peak current density (in mAmg À 1 of Pt) 427.5 which is 14.84 times greater than that of composite containing 0.1 wt % Pt (28.80) in dark condition and under visible light, 0.4 wt % Pt and 0.6 wt % Pt exhibit 1.89 and 1.28 times greater activity in reference to MOR than that of dark. CA study reveals that 0.6 wt % Pt exhibits steady current density (20.91 mAmg À 1 of Pt) 209 times higher compared to that of composite having 0.1 wt % Pt (0.264 mAmg À 1 of Pt). The photocurrent response of 0.4 wt % Pt is found the best among the electrodes examined. The EIS data also reveal enhanced interfacial charge transfer in photo-irradiated electrodes. The HPLC and GCMS studies identify MOR products and help to draw the mechanisms.

Pd Nanoparticle-Decorated Novel Ternary Bi2O2CO3-Bi2MoO6-CuO Heterojunction for Enhanced Photo-electrocatalytic Ethanol Oxidation

“…The potential dependence interpretation of the Nyquist plot for the EOR on the quaternary catalyst Pd/BM-BOCC was also executed at different constant potentials in the range of −0.1 to −0.35 V under light illumination (Figure d). The Nyquist diameter continuously increases with increasing potential from −0.35 to −1.0 V. This is due to the carbonaceous intermediate’s species poisoning the catalyst at a higher potential. ,,, …”

“…The HPLC profiles of ethanol oxidation products obtained after 6000 s of CA at a fixed potential of −0.3 V ,, using quaternary Pd/BM-BOCC catalysts under dark and illuminated conditions are exhibited in Figure B, and the retention time of the pure acetate compound is also drawn using its known concentration for evidence. The retention tenures of 7.12 and 8.59 min refer to the formation of carbonate and acetate, respectively.…”

“…The distinguished peak of Pd, Bi 2 O 2 CO 3, Bi 2 MoO 6 , and CuO in Pd/Bi 2 O 2 CO 3- Bi 2 MoO 6 -CuO (Pd/BM-BOCC) reveals the formation of a quaternary heterojunction synthesized by the solvothermal–chemical reduction method. The mass % of Pd, Bi 2 O 2 CO 3 , Bi 2 MoO 6 , and CuO in the Pd/BM-BOCC catalyst is determined using Rietveld refinement 50 , 51 of PXRD data ( Figure S1 ) and observed 22.6 wt % Pd, 33.61 wt % Bi 2 MoO 6 , 39.45 wt % Bi 2 O 2 CO 3 , and 4.34 wt % CuO, which agree well with the experimental percentage.…”

“…The experimental framework of the photoelectrooxidation system was depicted in our earlier study. 14,16,51 4.8. Analysis of EOR Products by FTIR and HPLC.…”

“…The light intensity was measured using a lux meter (LX-101A). The experimental framework of the photo-electrooxidation system was depicted in our earlier study. ,, …”