Development of Na2Ti6O13/CuO/Cu2O heterostructures for solar photocatalytic production of low-carbon fuels. (February 2020)

• Record Type: Journal Article
• Authors: Ibarra-Rodríguez, Luz I.; Huerta-Flores, Ali M.; Torres-Martínez, Leticia M.
• Is Part Of: Materials research bulletin. Volume 122(2020)
• Publication Date: 2020-02
• Subjects: Na2Ti6O13 -- CuO/Cu2O -- Photocatalytic hydrogen production -- CO2photoreduction -- Tunnel structure; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2019.110679
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Na2 Ti6 O13 /CuO/Cu2 O materials were prepared by an impregnation method. Different proportions of CuO/Cu2 O (CC) were obtained. Cu2 O favored H2 evolution while CuO enhanced CO2 photoreduction. Na2 Ti6 O13 -0.1% CC exhibited the best H2 production (33 μmolg -1 h -1 ). Na2 Ti6 O13 -5% CC showed the highest yield of HCHO (25 μmolg -1 h -1 ). Abstract: Na2 Ti6 O13 /CuO/Cu2 O materials were prepared by solid-state and impregnation method, using copper oxide as cocatalyst (CC, 0.1%–5%). The catalytic activity was evaluated for H2 evolution and CO2 reduction. XPS analysis revealed the presence of Cu2 O and CuO in different proportions. Na2 Ti6 O13 impregnated with 0.1% of cocatalyst exhibits majoritary the Cu2 O phase; while Na2 Ti6 O13 with 5% of cocatalyst shows mainly CuO. Electrochemical measurements showed higher photocurrent and lower resistance to charge transference in Na2 Ti6 O13 -0.1% CC, associated with better a charge flow. Na2 Ti6 O13 -0.1% CC exhibited the highest H2 production (33 μmol g -1 h -1 ) and Na2 Ti6 O13 -5% CC showed the best CO2 conversion to CH2 O (25 μmol g -1 h -1 ) and CH3 OH (4.6 μmol g -1 h -1 ). A major content of Cu2 O phase favored the H2 evolution by the formation of a Z-scheme, where the strong negative character of the CB of Cu2 O enhances the kinetics of H2 O reduction, while a higher content of CuO improved CO2 adsorption and reduction.