TY - JOUR
T1 - Flexible and free-standing polyvinyl alcohol-reduced graphene oxide-Cu2O/CuO thin films for electrochemical reduction of carbon dioxide
AU - Sheelam, Anjaiah
AU - Muneeb, Adil
AU - Talukdar, Biva
AU - Ravindranath, Rini
AU - Huang, Song Jeng
AU - Kuo, Chun Hong
AU - Sankar, Raman
N1 - Publisher Copyright:
© 2020, Springer Nature B.V.
PY - 2020/9/1
Y1 - 2020/9/1
N2 - Abstract: Flexible and free-standing thin films were fabricated and employed directly as working electrodes for the electrochemical reduction of CO2 in 0.5 N KHCO3 at 25 °C, in which, various sizes of Cu2O nanocubes (~ 27 ± 2, 37 ± 3, 62 ± 4 and 207 ± 3 nm) with different extent of surface oxidation (13, 20, 66, and 64% of Cu(II)) were reinforced on to polyvinyl alcohol/reduced graphene oxide matrix (PVA/rGO/(Cu2O/CuO_X, where, X = without halide, Cl, Br and I). The size of Cu2O nanocubes and their surface oxidation were systematically altered by the addition of 1 mL of 10 mM sodium halides (NaCl, NaBr, and NaI) during the synthesis. Energy-dispersive X-ray spectroscopy mapping displayed the specific adsorption of Cl− ions over the Cu2O surface, whereas Br− and I− ions did not show such behaviour. PVA/rGO/(Cu2O/CuO_Cl) thin film exhibited a low overpotential of 20 mV for CO2 reduction reaction and, ~ 60 and ~ 7 times higher current density at − 0.80 V vs. RHE compared to that of the PVA/rGO/(Cu2O/CuO), PVA/rGO/(Cu2O/CuO_Br) ≈ PVA/rGO/(Cu2O/CuO_I), respectively. Gas chromatography and 1H-NMR analyses confirmed methanol as the single liquid product, with a faradaic efficiency of 63% at − 0.75 V vs. RHE on PVA/rGO/(Cu2O/CuO_Cl) thin film. Graphic abstrat: [Figure not available: see fulltext.].
AB - Abstract: Flexible and free-standing thin films were fabricated and employed directly as working electrodes for the electrochemical reduction of CO2 in 0.5 N KHCO3 at 25 °C, in which, various sizes of Cu2O nanocubes (~ 27 ± 2, 37 ± 3, 62 ± 4 and 207 ± 3 nm) with different extent of surface oxidation (13, 20, 66, and 64% of Cu(II)) were reinforced on to polyvinyl alcohol/reduced graphene oxide matrix (PVA/rGO/(Cu2O/CuO_X, where, X = without halide, Cl, Br and I). The size of Cu2O nanocubes and their surface oxidation were systematically altered by the addition of 1 mL of 10 mM sodium halides (NaCl, NaBr, and NaI) during the synthesis. Energy-dispersive X-ray spectroscopy mapping displayed the specific adsorption of Cl− ions over the Cu2O surface, whereas Br− and I− ions did not show such behaviour. PVA/rGO/(Cu2O/CuO_Cl) thin film exhibited a low overpotential of 20 mV for CO2 reduction reaction and, ~ 60 and ~ 7 times higher current density at − 0.80 V vs. RHE compared to that of the PVA/rGO/(Cu2O/CuO), PVA/rGO/(Cu2O/CuO_Br) ≈ PVA/rGO/(Cu2O/CuO_I), respectively. Gas chromatography and 1H-NMR analyses confirmed methanol as the single liquid product, with a faradaic efficiency of 63% at − 0.75 V vs. RHE on PVA/rGO/(Cu2O/CuO_Cl) thin film. Graphic abstrat: [Figure not available: see fulltext.].
KW - H-NMR
KW - CO electrochemical reduction
KW - Nanocubes
KW - Reduced graphene oxide
KW - Thin film electrodes
UR - http://www.scopus.com/inward/record.url?scp=85087424647&partnerID=8YFLogxK
U2 - 10.1007/s10800-020-01450-z
DO - 10.1007/s10800-020-01450-z
M3 - Article
AN - SCOPUS:85087424647
SN - 0021-891X
VL - 50
SP - 979
EP - 991
JO - Journal of Applied Electrochemistry
JF - Journal of Applied Electrochemistry
IS - 9
ER -