Photothermal Coupling Factor Achieving CO₂ Reduction Based on Palladium-Nanoparticle-Loaded TiO₂

Abstract

Solar fuels have attracted great interest as an alternative use for solar energy. However, the challenges are high temperatures and low solar utilization for thermochemical and photochemical conversion methods, respectively. To lower the temperature in thermochemistry and increase solar energy utilization, a photothermochemical cycle (PTC) has been reported for carbon dioxide (CO2) reduction and improved by palladium-nanoparticle-loaded TiO2 (PNT). A maximum and stable carbon monoxide (CO) production of 11.05 μmol/(h g) is demonstrated using 1.0PNT, which is 8.27× the CO produced by P25 in the PTC. The PNT can enhance light utilization by a red-shifted photoresponse range and visible light absorbance of localized surface plasmon resonances (LSPRs). Photoinduced electron and hole pairs (EHPs) could be more readily separated. More available charge carriers would induce more photoinduced vacancies in the photoreaction, which serve a key role in the PTC. Additionally, Pd can promote CO2 absorbance to form Pd-CO2 – and Pd-CO2 –-VO on the defective surface in the thermal reaction. Finally, CO production can be enhanced by a photothermal coupling factor, and a reaction mechanism is proposed for the complete cycle on the basis of both theoretical calculations and experiments.

Coupling of Solar Energy and Thermal Energy for Carbon Dioxide Reduction: Status and Prospects

“…For catalytic reactions related to the combination of solar energy and thermal energy, several terms were often used in the literature, such as photothermal, photo‐thermal, and photo‐thermo catalytic reactions . Currently, there is no strict definition for each term, which brings about serious confusion.…”

“…Currently, there is no strict definition for each term, which brings about serious confusion. In fact, there are mainly three scenarios: 1) A photo‐thermochemical cycle in which photocatalysis and thermocatalysis are realized separately (Figure a) . In the first half reaction, oxygen vacancies are created by UV/Vis light through photocatalysis.…”

Modulation of terahertz properties of 3D ceramic photonic crystals via post‐creation non‐metal anion doping treatment

“…The asymmetric O 1 s peaks of these samples could all be divided into the combination of two peaks. The peak with the binding energy value at ~530.0 eV could be assigned to O species in the lattice (O L ), while the peak with the binding energy value at ~531.7 eV could be assigned to O species near the vacancies or defects (O V ) . Table summarizes the peak area ratios of O V and O L in both the undoped and doped rutile TiO 2 ceramic 3D‐TPC samples.…”

Photothermal materials for efficient solar powered steam generation

“…Metal oxides are usually used as photocatalytic and photothermal catalytic materials in hydrogen production [70,71], solar-driven CO x reduction to hydrocarbons [72,73]. Recently, metal oxides are used in the application of solar water evaporation.…”