CuO Decoration Controls Nb₂O₅ Photocatalyst Selectivity in CO₂ Reduction

Abstract

The reformation of CO 2 through photocatalytic processes to obtain products with high energy value and compatibility with the current energy infrastructure is a compelling strategy to minimize the emission of CO 2 into the atmosphere, one of the main greenhouse gases. However, practical application of such a photocatalytic system requires significant efforts for improved CO 2 photoreduction performance and product selectivity. Thus, in the present work, CuO nanoparticles were combined with Nb 2 O 5 in order to improve the photocatalytic properties of these semiconductors in the CO 2 photoreduction process. Nb 2 O 5 / CuO heterojunctions were prepared via a solvothermal treatment method, while the experimental tools, such as FESEM, HRTEM, and DRS, were employed to evaluate the microstructural and electronic properties. We describe how CuO decoration over Nb 2 O 5 adjusts its selectivity for CO 2 reduction to CH 4 , HCOOH, or H 3 CCOOH in different contents. An investigation of CO 2 photoreduction using different electron donors/scavengers (water, sodium oxalate, and potassium bromate) under ultraviolet radiation revealed that its decoration influences local CO production by modifying the selectivity. CO has been confirmed as the main intermediate for HCOOH and CH 3 COOH production, and CO 2 reduction efficiency increases at low CuO content (2.5% wt), leading to the formation of soluble hydrocarbons, and increases for CH 4 in higher amounts (10% wt).

Preparation and Application of Nb2O5 Nanofibers in CO2 Photoconversion

“…Studies reveal that the surface acidity of the photocatalyst can influence the selectivity of the products generated from CO 2 photoreduction [11,12]. The size of nanoparticles and composition of the photocatalysts can also influence the selectivity during the photoreduction reaction [41].…”

“…Niobium pentoxide (Nb 2 O 5 ) is a semiconductor that is receiving attention because it possesses similar features to TiO 2 and has a promising performance when applied in CO 2 photoconversion [10][11][12]. Silva et al [12] studied the photocatalytic activity of Nb 2 O 5 particles after surface modifications with peroxo groups.…”

Ultrathin 2D/2D ZnIn2S4/g‐C3N4 Nanosheet Heterojunction with Atomic‐Level Intimate Interface for Photocatalytic Hydrogen Evolution under Visible Light

“…[6][7][8][9] According to the research of titanium dioxide (TiO 2 ) single crystal in photoelectrochemistry, Fujishima and Honda [10] pioneered the field of semiconductor photocatalysis. However, the wide band gap of metal oxide such as ZnO, [11][12][13][14] SnO 2 , [15][16][17][18] Nb 2 O 5 , [19][20][21] etc., makes them only respond to near-ultraviolet or ultraviolet light, resulting in low efficiency of solar energy. In fact, visible light accounts for 43% of sunlight, while ultraviolet ray accounts for merely 4%.…”

Ce2O3/BiVO4 Embedded in rGO as Photocatalyst for the Degradation of Methyl Orange under Visible Light Irradiation

“…The qualitative analysis of semiconductor materials using UV-vis is based on the use of light in the UV and visible part of the electromagnetic spectrum to effect the excitation of electrons in either the atomic or molecular ground state to higher energy levels. This gives rise to an absorbance, which is at wavelengths that are specific to each molecule or material being analysed [42,43].…”