Alkaline earth metal oxide nanocluster modification of rutile TiO2 (110) promotes water activation and CO2 chemisorption

摘要: Metal oxide photocatalysts are widely studied for applications in solar driven environmental remediation, antimicrobial activity, hydrogen production and CO2 reduction to fuels. Common requirements each technology include absorption of visible light, reduced charge carrier recombination the ability activate initial molecule be it a pollutant, water or CO2. The leading photocatalyst is some form TiO2. A significant amount work has been undertaken modifying TiO2 induce light absorption. structure composition catalyst should facilitate separation electrons holes having active sites on important promote adsorption activation molecules interest. In this paper we present first principles density functional theory (DFT) study modification rutile (110) with nanoclusters alkaline earth metal oxides (MgO, Ca, BaO) focus effect surface key properties. CaO BaO induces predicted red shift all cases, photoexcited localise oxygen nanocluster Ti sites, thus enhancing separation. presence these non-bulk provides highly adsorption. On MgO-rutile, adsorbs molecularly overcomes barrier only 0.36 eV dissociation whereby hydroxyls stabilised. CaO- BaO-modified dissociatively. We attribute high lying O 2p states modifiers which available interact water, as well like geometry around site. Upon preferred binding mode tridentate carbonate-like species, characterised by vibrational modes. carbonate bound up 4 eV. Thus heterostructures can interesting capture, helping alleviate problem emissions.