In-situ prepared plasmonic V2O3−x catalyst: Catalyzing CO2 reduction via surface plasmon resonance in near-infrared region

Excessive CO₂ emission triggers many hazards such as global warming, glacier melting, and sea level rise, which seriously threaten the ecological balance and human survival. Converting CO₂ into high-value fuels and chemicals has become an effective way to reduce carbon emissions and realize the utilization of carbon resources. The reverse water-gas shift reaction (RWGS) is a key step in the production of C₁ feedstock. In the conventional thermally catalyzed RWGS reaction, a large amount of energy input is required to drive the reaction due to the high stability of the C=O bond (≈750 kJ mol^-1) and the fact that the reaction is endothermic (ΔH^⊝(298K) = 42.1 kJ mol⁻¹). To overcome these challenges, solar-driven catalysis was developed, which utilizes the solar energy as only energy source to driving the overall chemical reactions, and involve multiple processes of photothermal conversion, photocatalysis and plasmon. Compared with traditional photocatalysis and photothermal catalysis, it has significant 

With the world paying great attention to climate change, a series of environmental crises caused by excessive carbon dioxide emissions, such as global warming, the accelerated melting of glaciers, and the continuous rise of sea levels, are seriously threatening the ecological balance of the earth and the future living space of human beings. Converting carbon dioxide into high-value fuels and chemicals has become a key strategy to address this crisis and achieve effective carbon emission reduction and carbon resource utilization. Among them, the reverse water-gas shift reaction (RWGS), as a core step in the production of C1 feedstock, has attracted much attention from researchers.

The traditional thermally catalyzed RWGS reaction faces significant challenges. The high stability of the C=O bond (approximately 750 kJ/mol) and the endothermic nature of the reaction itself (ΔH^⊝(298K) = 42.1 kJ/mol) lead to the need for a large amount of energy input to drive the reaction, which undoubtedly increases the cost and limits large-scale application. To break through this dilemma, solar-driven catalytic technology has emerged. This technology skillfully utilizes solar energy, integrating multiple processes such as photothermal conversion, photocatalysis, and plasmonics. With the synergistic effect of photons and phonons, it shows significant advantages in improving the utilization efficiency of solar energy and catalytic performance, bringing new hope for solving energy and environmental problems.

In the field of solar-driven catalysis, the development of highly efficient catalysts with a plasmonic effect is the core goal for the efficient conversion of carbon dioxide. In the early days, although plasmonic catalysts based on noble metal nanoparticles such as gold, silver, and platinum had some achievements, they could only work under ultraviolet-visible light irradiation and were costly, making widespread application difficult. In recent years, plasmonic semiconductors such as doped metal oxides, non-stoichiometric Cu_2-xS compounds, and oxygen-deficient metal oxides have gradually become research hotspots. These novel materials significantly increase the concentration of free carriers through simple doping. When the carrier concentration reaches 10²⁰ ~ 10²¹ cm^-3, the absorption wavelength of the localized surface plasmon resonance (LSPR) successfully shifts to the near-infrared-infrared region, greatly expanding the utilization range of solar energy.

Recently, an exciting scientific research achievement has been announced. The research team has successfully prepared a novel defective state vanadium oxide semiconductor, V₂O_3-x nanoparticles, through in-situ deoxygenation of V₂O₃ under light irradiation. V₂O_3-x not only has inherent chemical stability and abundant oxygen vacancies, providing a large number of active sites for the conversion of carbon dioxide, reducing the activation energy barrier, and promoting the generation of carbon monoxide, but also exhibits a unique plasmonic effect. The oxygen vacancies induced by light irradiation increase the carrier concentration of V₂O_3-x by 10 times, reaching 2.51×10²¹ cm^-3, corresponding to the LSPR absorption in the near-infrared range of 700 ~ 1500 nm, rapidly and efficiently increasing the local surface temperature of the catalyst.

In the test of the RWGS reaction, V₂O_3-x demonstrated excellent performance, with a carbon monoxide conversion rate as high as 668.48 mmol g^-1 h^-1, a selectivity of over 99.9%, and long-term stability for 90 hours. The research team, by means of in-situ spectroscopic characterization and density functional theory calculations, has thoroughly elucidated its catalytic mechanism: using oxygen vacancies to adsorb and activate carbon dioxide, injecting the d-band electrons of vanadium into the antibonding orbitals of carbon dioxide, reducing the activation energy barrier, and enabling the rapid conversion and desorption of carbon dioxide. This innovative research achievement not only greatly improves the utilization rate of sunlight, significantly increases the local surface temperature of the catalyst, enhances the catalytic performance and cost-effectiveness, but also provides a practical method for the practical application of carbon dioxide conversion. It is expected to play a crucial role in alleviating global climate change and promoting the development of green energy in the future, leading the relevant field to a new stage of development.

This work was supported by the Hefei National Laboratory for Physical Sciences at the Microscale, National Key Research and Development Program of China (2021YFA1500402)，Hefei Science Center of the Chinese Academy of Sciences, Fujian Institute of Innovation of the Chinese Academy of Sciences, the National Natural Science Foundation of China (NSFC, 22471252, 21571167, 51502282 and 22075266), the Fundamental Research Funds for the Central Universities (WK2060190053 and WK2060190100). The in-situ XANES measurements were performed at the beamline BL12B-b in the NSRLof USTC.

About the Author

Liu Bo is a professor at the University of Science and Technology of China (USTC) and a concurrently-appointed researcher at the National Research Center for Microscale Matter Science in Hefei. He is a recipient of a national young talent program and focuses on the design and synthesis of functional coordination compounds as well as the research on their functional applications. He obtained his Ph.D. degree from the National Institute of Advanced Industrial Science and Technology (AIST), Japan in 2009. Subsequently, he conducted postdoctoral research at Ruhr University Bochum/University of Karlsruhe in Germany (as a Humboldt Fellow) and at the University of Liverpool in the UK (as a Marie Curie Fellow). He joined USTC in January 2015.

About Nano Research

Nano Research is a peer-reviewed, open access, international and interdisciplinary research journal, sponsored by Tsinghua University and the Chinese Chemical Society, published by Tsinghua University Press on the platform SciOpen. It publishes original high-quality research and significant review articles on all aspects of nanoscience and nanotechnology, ranging from basic aspects of the science of nanoscale materials to practical applications of such materials. After 18 years of development, it has become one of the most influential academic journals in the nano field. Nano Research has published more than 1,000 papers every year from 2022, with its cumulative count surpassing 7,000 articles. In 2024 InCites Journal Citation Reports, its 2024 IF is 9.0 (8.7, 5 years), and it continues to be the Q1 area among the four subject classifications. Nano Research Award, established by Nano Research together with TUP and Springer Nature in 2013, and Nano Research Young Innovators (NR45) Awards, established by Nano Research in 2018, have become international academic awards with global influence.