Rational design of hybrid nanomaterials for enhanced CO2 capture: A way towards greener environment †

Abstract

Carbon dioxide (CO2) emission remains one of the solicitude concerns for society to achieve net-zero emissions. The functionalized nanocrystals have recently exhibited their potential to capture CO2. We synthesized ZnO and Zn1-xAgxO nanocrystals by chemical co-precipitation to fulfil the aim of CO2 capture. The X-ray diffraction spectra of ZnO nanocrystals have depicted their hexagonal wurtzite structure; however, Ag doping shifts the (100), (002), and (101) reflection peaks toward higher 2θ values, indicating lattice distortion and a reduction in crystallite size. Besides, the X-ray photoelectron spectroscopy analysis shows that Zn1-xAgxO nanocrystals exhibit around 0.5 at.% content of Ag in the ZnO lattice. Henceforth, the nanocrystals have been functionalized with N-annulated perylene tetraester (PT) to enhance their reactivity. The ability of these nanocrystals to capture CO2 and its relevance for sustainable climate initiatives have been examined by CO2-temperature programmed desorption (CO2-TPD) studies. This study reveals that the CO2 molecules are effectively adsorbed on the PT-functionalized Zn1-xAgxO nanocrystals and do not detach until 400 °C, which has been explained using the Polanyi-Wigner relation. This investigation demonstrates a compelling aspect of maintaining an environmentally sustainable and pollution-free ecosystem.