Abstract
Photocatalytic reduction of CO2 into fuels is a promising route to reduce greenhouse gas emission, and it demands high-performance photocatalysts that can use visible light in the solar spectrum. Due to its broadband light adsorption, polydopamine (PDA) is considered as a promising photo-sensitization material for semiconductor photocatalysts. In this work, titanium oxides have been coated with PDA through an in-situ oxidation polymerization method to pursue CO2 reduction under visible light. We have shown that the surface coated PDA with a thickness of around 1 nm can enhance the photocatalytic performance of anatase under visible light to reduce CO2 into CO. Assisted with additional UV-vis adsorption and photoluminescence characterizations, we confirmed the sensitization effect of PDA on anatase. Furthermore, our study shows that thicker PDA coating might not be favorable, as PDA could decompose under both visible and UV-vis light irradiations. 13C solid-state nuclear magnetic resonance showed structural differences between thin and thick PDA coatings and revealed compositional changes of PDA after light irradiation.
Highlights
The large-scale consumption of fossil fuels rapidly increases atmospheric CO2 concentration that leads to the consequence of climate change
We focused on polydopamine (PDA), which is a polymer bioinspired by mussel adhesive proteins [21]
Our results suggest PDA could be a promising photosensitizer for anatase targeted for CO2 reduction applications
Summary
The large-scale consumption of fossil fuels rapidly increases atmospheric CO2 concentration that leads to the consequence of climate change. The photocatalysts could turn into artificial leaves which utilize only solar light and minimal reagents to enable a sustainable carbon cycle To reach such ambitious goal, semiconductor materials will play a very important role owing to their desired photocatalytic activity [5,6]. In 1979, Inoue et al [7] initially reported semiconductor including TiO2 , WO3 , ZnO, CdS, GaP and SiC as photocatalysts on reduction of CO2 into organic compounds such as methane, methanol, and formic acid. Encouraged by this pioneering work, various kinds of semiconductor photocatalysts (e.g., Fe2 O3 , Cu2 O, BiVO4 , Zn2 GeO4 and g-C3 N4 ) have been developed and tested, overall their performance was far from satisfaction. It is recommended that the photocatalytic performance (especially about the organic products) should be evaluated judiciously and careful characterization of photo-stability is necessary
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
