Graphene-modified g-C3N4/ α-Fe2O3 systems for light-induced hydrogen generation

abstract

Photocatalysis represents an advanced and efficient technology for harnessing light energy. The non-toxicity, affordability, and versatility of this technique render it particularly attractive for hydrogen production via water splitting. Nevertheless, the primary challenge lies in identifying materials capable of efficiently catalyzing the water splitting reaction upon exposure to light. This study presents the influence of the quantity of hematite and graphene on g-C3N4 in the context of hydrogen generation from methanol-water decomposition under UVC irradiation. Pure g-C3N4 exhibits the highest hydrogen generation efficiency. However, adding hematite decreases photocatalytic efficiency, likely due to the formation of a type II heterojunction between alpha-Fe2O3 and gC3N4, which reduces the overall reduction capacity of the system. While incorporating graphene into the g-C3N4/ alpha-Fe2O3 system enhances photocatalytic efficiency by improving electron mobility and prolonging the lifetime of photo-generated excitons, the highest yield was achieved with BUF10/GNP0.5. This research offers valuable insights into charge transfer and separation processes for photo-generated excitons within the g-C3N4/alpha-Fe2O3 and g-C3N4/alpha-Fe2O3/graphene systems in the context of light-induced hydrogen production.

keywords

PHOTOCATALYTIC H-2 EVOLUTION; CHARGE-TRANSFER; CO2 REDUCTION; PERFORMANCE; NANOCOMPOSITES; AG; G-C3N4/ALPHA-FE2O3; DEGRADATION; COMPOSITES; EFFICIENCY

subject category

Materials Science

authors

Touati, W; Edelmannová, MF; Karmaoui, M; Bekka, A; Furgeaud, C; Alaoui, C; Allah, IK; Figueiredo, B; Labrincha, JA; Arenal, R; Koci, K; Tobaldi, DM

Groups

G4 - Renewable Materials and Circular Economy

Projects

CICECO - Aveiro Institute of Materials (UIDB/50011/2020)

CICECO - Aveiro Institute of Materials (UIDP/50011/2020)

Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)

Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)

acknowledgements

We would like to express our gratitude to the Algerian Ministry of Higher Education and Scientific Research for funding Wassila Touati's visit to the University of Aveiro, through the National Exceptional Scholarship Program (PNE) . R.A. gratefully acknowledges the support from the Spanish MICIU (PID2023-151080NB-I00/AEI/10.13039/501100011033 and CEX2023-001286-S MICIU/AEI/10.13039/501100011033) and by the DGA project E13-23R. The TEM studies were conducted at the Laboratorio de Microscopias Avanzadas, Universidad de Zaragoza, Spain. Kamila Koci is thankful to the Large Research Infrastructure ENREGAT (project No LM2023056) . This work was partly developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MCTES (PIDDAC) . This work was partly supported by the Italian Ministry of Research (MUR) in the framework of the National Recovery and Resilience Plan (NRRP) , funded by the European Union - NextGenerationEU, M4C2, within the NRRP project NFFA-DI, CUP B53C22004310006, IR0000015. "I-PHOQS" Grant (CUP B53C22001750006) and under the complementary actions to the NRRP, "Fit4MedRob" Grant (PNC0000007, CUP B53C22006960001) and "ANTHEM" Grant (PNC0000003, CUP B53C22006710001) , funded by NextGenerationEU.