Reduced graphene oxide/NH2-MIL-125(Ti) composite: Selective CO2 photoreduction to methanol under visible light and computational insights into charge separation. Issue 42 (December 2020)

• Record Type: Journal Article
• Authors: Olowoyo, Joshua O.; Saini, Upasana; Kumar, Manoj; Valdés, Héctor; Singh, Hitendra; Omorogie, Martins O.; Babalola, Jonathan O.; Vorontsov, Alexander V.; Kumar, Umesh; Smirniotis, Panagiotis G.
• Is Part Of: Journal of CO₂ utilization. Issue 42(2020)
• Publication Date: 2020-12
• Subjects: Charge separation -- CO2reduction -- DFTB calculations -- Metal-organic frameworks -- Photocatalysis -- Reduced graphene oxide; Carbon dioxide -- Periodicals; Carbon dioxide -- Environmental aspects -- Periodicals; Carbon dioxide mitigation -- Periodicals; Carbon dioxide; Carbon dioxide -- Environmental aspects; Carbon dioxide mitigation; Periodicals; 628.53205
• DOI: 10.1016/j.jcou.2020.101300
• Languages: English
• ISSNs: 2212-9820

Abstract

Graphical abstract: Abstract: The development of visible-light active photocatalysts is highly desirable for CO2 reduction to hydrocarbons and alcohols using sunlight. Here, we report the metal-organic frameworks (MOF) of amino-benzene dicarboxylate with titanium oxocluster center (NH2 -MIL-125(Ti)) and modified with reduced graphene oxide (RGO), RGO-NH2 -MIL-125(Ti), ideal for the visible-light-driven photocatalytic reduction of CO2 to hydrocarbons and methanol. The catalyst provides high quantum efficiency and selectivity for methanol. The cluster model and self-consistent charge density functional tight binding methods were used to investigate the photogenerated charge separation for NH2 -MIL-125(Ti). The quantum modelling suggests that holes were accumulated in the central ring Ti8 O8 (OH)4, where strongly adsorbed electron donor, triethanolamine, undergoes photooxidation while electrons were located in the organic ligand of MOF including the NH2 group. The binding affinity of NH2 reaction sites to CO2 possibly work to improve the photocatalytic reduction of CO2 to methanol. The RGO also play an important role for charge separation and better photocatalytic reduction with RGO-NH2 -MIL-125(Ti).