Novel Co3O4 @ CoFe2O4 double-shelled nanoboxes derived from Metal–Organic Framework for CO2 reduction

Abstract

Fabrication heterojunction semiconductors with proper band alignments and reasonable morphologies for photocatalytic CO2 reduction are eliciting increased attention. Hence, a novel Z-scheme heterojunction of Co3O4 @ CoFe2O4 hierarchical hollow double-shelled nanoboxes was designed via Metal–Organic Framework engaged templating method and hydrothermal reaction procedure. An online spectral mean has been employed to study the reaction process in this work. The structural and optical properties of Co3O4 @ CoFe2O4 was comprehensively identified by a series of analytical characterizations. The characterization results depicted that Co3O4 @ CoFe2O4 hierarchical hollow double-shelled nanoboxes were constructed, and the surfaces of Co3O4 nanocubes were covered by CoFe2O4 Nanosheets (NSs). In general, the unique Z-scheme heterojunction of as-synthesized materials facilitated the interfacial separation and transfer of photoexcited carriers. And hierarchical hollow structure offered larger surface area, increased CO2 adsorption properties and exposed more active sites. The Co3O4 @ CoFe2O4 showed the optimum CO2 photo-reduction activities, the CH4 and CO production rates were 2.06 μmol h−1 and 72.2 μmol h−1 respectively. This work validated that Co3O4 @ CoFe2O4 is a powerful photocatalyst for CO2 reduction, and this hybrid structures can also pave an insight into the development of novel recyclable heterojunctions to practical application.