CO2 reduction by photocatalytic and photoelectrocatalytic approaches over Eu(III)-ZnGa2O4 nanoparticles and Eu(III)-ZnGa2O4/ZnO nanorods

Electrochemical CO2 Reduction over a MoS2/Mo Electrode

“…These results suggest that a decrease in the H 2 production leads to a corresponding decrease in the saturated alkane production owing to the reduction in the number of hydrogen atoms on the electrode surface. Further, the CO concentration increases from 3.3 to 92.8 ppm, indicating a 28-fold production enhancement, consistent with previously reported results [39][40][41]. Similarly, the C 2 H 4 and CH 4 concentrations increase from 0.9 to 8.6 ppm and 19.2 to 27.5 ppm, indicating 9.6 and 1.4 times production enhancements, respectively.…”

“…Abundant surface H is expected during this process. Further, CO 2 is adsorbed as either OCHO* or HOOC* [39][40][41]; OCHO* is converted to formate (HCOO − ), which is observed over MoS 2 , while HOOC* converts to surface O≡C* via the reaction HOOC* + H+ + 𝑒 − → O≡C* + H 2 O. When O≡C* strongly adheres to the MoS 2 surface, CO desorption is suppressed [18], which results in a low CO production as shown in Fig.…”

“…Further, O≡C* is expected to be converted to CHO via the reaction O≡C + H + + 𝑒 − → *CHO [39][40][41]; additional processes include *CHO + 4H + + 4𝑒 − → *CH 3 + H 2 O and *CHO + 2H + + 2𝑒 − → *OCH 3 . The surface *CH x species may associate to generate C 2−4 hydrocarbon compounds via C-C coupling [39][40][41], and CH 4 is produced via *CH 3 + H + + 𝑒 − → CH 4 . The surface *OCH 3 is desorbed as CH 3 OH, which is mainly observed over the Au/MoS 2 /Mo electrode [46].…”

Electrochemical CO2/CO Reduction and C–C Coupling Path for Mimicking Fischer–Tropsch Synthesis over Cadmium Electrodes

“…The conversion of CO 2 into chemical fuels is a significant challenge for the future energy and environmental roadmap. − Two strategic approaches have been employed to accelerate this task, including the electrochemical CO 2 reduction (EC CO 2 R) method and the development of suitable electrodes. − Various pure metals from the periodic table have been extensively tested as electrodes for EC CO 2 R, showing different CO 2 reduction products such as CO and formate. The selectivity and productivity of these metals depend on their electron configuration and the nature of their surface states. − For instance, In and Sn in the p-block have shown high Faradaic efficiency (FE) and selectivity for formate production, − while Cu in group 11 has been found to be effective in producing CH 4 , C 2 H 4 , and alcohols. − Zn has been widely studied for producing syngas (CO and H 2 ) or CO. − However, cadmium (Cd), which belongs to the same group 12 as Zn, has relatively been less employed for CO 2 reduction. − Ongoing research on pure metals is opening up new CO 2 reaction pathways by using new reaction conditions such as electrolytes and surface engineering of support electrodes. − …”

Progress and perspectives on 1D nanostructured catalysts applied in photo(electro)catalytic reduction of CO2

“…ZnO nanorods have good photo-response ability and good performance in carrier separation and transport, so they have been widely studied in the field of photocatalytic CO 2 RR. 194,195 The charge separation and transport performance could be further optimized by loading Cu 2 O on the tip of ZnO NRs to construct p–n junctions. CO was the main CO 2 reduction product, and the yield increased with the increase of Cu 2 O loading.…”