Photocatalytic CO2 capture on plasmonic copper nanoparticles in a biofluidic channel

Abstract

A CO2 capture and photocatalytic conversion system was designed to investigate heterogeneous catalytic reactions in a biofluidic channel. The photo-reacted species produced in a microalgae fluid sample were analyzed using in situ Raman scattering and gas chromatography with mass spectroscopy (GC–MS). Nanopore copper (II) sulfide–hollow nanospheres (CuS–HNS) and copper nanocubes (CuNCs) were exposed under the visible laser irradiation during photoreduction process under hydrated conditions. Several products of C1–C4 species from CO2 were identified during photocatalytic reaction depending on the surface reaction conditions. Spectral features and time-dependent Raman spectral behaviors were different from CuS–HNS and CuNCs. Representative species of methanol (C1) and acetone (C3) during CO2 reduction reaction were examined at 633 nm. Adsorption of CO2 onto Cu surface was studied to interpret the photocatalytic reactions using the density functional theory (DFT) calculations. Based on different spectral changes of Raman spectra onto CuS–HNS and CuNCs surfaces in a biofluidic mixture of Spirulina maxima solutions, microalgae appeared to have the potential to play significant roles in carbon capture.