Visible and Near‐Infrared Photothermal Catalyzed Hydrogenation of Gaseous CO₂ over Nanostructured Pd@Nb₂O₅

Abstract

The reverse water gas shift (RWGS) reaction driven by Nb2O5 nanorod‐supported Pd nanocrystals without external heating using visible and near infrared (NIR) light is demonstrated. By measuring the dependence of the RWGS reaction rates on the intensity and spectral power distribution of filtered light incident onto the nanostructured Pd@Nb2O5 catalyst, it is determined that the RWGS reaction is activated photothermally. That is the RWGS reaction is initiated by heat generated from thermalization of charge carriers in the Pd nanocrystals that are excited by interband and intraband absorption of visible and NIR light. Taking advantage of this photothermal effect, a visible and NIR responsive Pd@Nb2O5 hybrid catalyst that efficiently hydrogenates CO2 to CO at an impressive rate as high as 1.8 mmol gcat−1 h−1 is developed. The mechanism of this photothermal reaction involves H2 dissociation on Pd nanocrystals and subsequent spillover of H to the Nb2O5 nanorods whereupon adsorbed CO2 is hydrogenated to CO. This work represents a significant enhancement in our understanding of the underlying mechanism of photothermally driven CO2 reduction and will help guide the way toward the development of highly efficient catalysts that exploit the full solar spectrum to convert gas‐phase CO2 to valuable chemicals and fuels.

Emerging Applications of Plasmons in Driving CO2 Reduction and N2 Fixation

“…In addition, plasmon decay can lead to enhanced photothermal conversion, which has been employed to promote chemical reactions because reaction rates are generally dependent exponentially on temperature . Nb 2 O 5 catalysts loaded with Pd nanoparticles have recently been reported to be able to initiate the hydrogenation of gaseous CO 2 by heat generated from the plasmon resonance of the Pd nanoparticles under visible and NIR light . The investigation of using the plasmonic photothermal effect to enhance chemical reactions is still at its early stage.…”

Surface Plasmon Resonance‐Enhanced Visible‐NIR‐Driven Photocatalytic and Photothermal Catalytic Performance by Ag/Mesoporous Black TiO2 Nanotube Heterojunctions

“…[17][18][19][20] Ap ossible approachf or efficient conversion of solar energy is based on the photothermal effect of nanoparticles (NPs) to generate hot carrierst op articipate in redox reactions, or to dissipate the absorbed photon energy into heat to accelerate the reactionrate. [21][22][23][24][25] Titanium dioxide (TiO 2 )i st he most representative material for photocatalysis, which has the advantages of low cost, nontoxic, high photoelectric conversione fficiency,h igh photocata-lytic activity,h igh chemicals tability,l arge specific surface area and pore volume. [26][27][28][29] The anatase TiO 2 with ag ood photocatalytic property usually has ab and gap of about 3.2 eV.…”

Full‐Spectrum Solar‐Light‐Activated Photocatalysts for Light–Chemical Energy Conversion

“…Following this work, many other studies have been reported. Ozin et al [119] used Nb 2 O 5 nanorod-supported Pd nanocrystals with visible and NIR light to realize CO 2 reduction into CO. The CO 2 hydrogenation rate with this hybrid catalyst under visible and NIR light can reach 1.8 mmol h −1 g −1…”