Photocatalytic CO₂ Transformation to CH₄ by Ag/Pd Bimetals Supported on N-Doped TiO₂ Nanosheet

Abstract

To develop photocatalysts with desirable compositions and structures for improving the efficiency and selectivity of CO conversion to CH under mild conditions is of great importance. Here, we design an effective photocatalyst of bimetal (Ag/Pd) nanoalloys supported on nitrogen-doped TiO nanosheet for CO conversion. Such a novel photocatalyst combines multiple advantages of abundant Ti ions, oxygen vacancies, and substitutional nitrogen that are favorable for catalyzing CO reduction. It was found that CO could be efficiently transformed to CH under mild conditions, i.e., in aqueous solution and at atmospheric pressure and room temperature. The maximum production rate of CH can reach 79.0 μmol g h. Moreover, the Ag/Pd bimetals supported on N-doped TiO nanosheet exhibit high selectivity to CH. The as-synthesized photocatalyst can be well recycled for CO reduction.

Recent Advances in TiO2-Based Photocatalysts for Reduction of CO2 to Fuels

“…Metals and metal oxides have been frequently employed as cocatalysts with TiO 2 to improve the performance of TiO 2 [35,75,[81][82][83][84][85][86][87][88][89][90][91][92][93][94][95][96].…”

2D Titanium/Niobium Metal Oxide‐Based Materials for Photocatalytic Application

“…Apart from monometallic metals, bimetallic metals also showed a great influence on the enhancement of the photocatalytic performance of 2D TNMOs due to the unique structural properties . For instance, Tan et al[82a] combined Ag/Pd bimetal nanoalloys with N‐doped TiO 2 NS by a facile approach using hydrazine as the reducing reagent for the efficient photocatalytic CO 2 conversion.…”

“…Apart from monometallic metals, bimetallic metals also showed a great influence on the enhancement of the photocatalytic performance of 2D TNMOs due to the unique structural properties . For instance, Tan et al[82a] combined Ag/Pd bimetal nanoalloys with N‐doped TiO 2 NS by a facile approach using hydrazine as the reducing reagent for the efficient photocatalytic CO 2 conversion. In comparison with the single‐component Ag (or Pd)‐TiO 2 composite, the Ag x Pd y /TiO 2 binary photocatalysts showed a strong light absorption, effective charge separation efficiency, and thus the improved photocatalytic performance (such as activity, selectivity, and stability).…”

“…Inspired by the nature plant of a peapod, Chen et al[82b] unidirectionally implanted spherical Au@Nb core‐shell plasmonic NPs with a nanometric break into the cavity of the tubular protonated H x K 1 − x NbO 3 nanoscrolls for efficient dye photodegradation and water splitting. Au NPs within the niobate NSs in Au@Nb@H x K 1 − x NbO 3 showed uniformity, the better filling efficacy, and the distinct elemental contrast.…”

“…For example, Lin et al prepared Ag/Cu bimetal nanoalloy‐modified K 4 Nb 6 O 17 nanocomposites by reduction of CuSO 4 and then impregnated AgNO 3 followed by thermal calcination, showing the enhanced photocatalytic inactivation of Escherichia coli ( E. coli ) under visible‐light irradiation [82c]. The photocatalytic antibacterial activity of the Ag‐modified sample was higher than that of the Cu‐modified sample due to the hindered electron–hole recombination rate of AgO x as compared with that of CuO.…”