# A breath of fresh air in plasmonic catalysis: Black gold and solar light’s renaissance
The group of Prof. Vivek Polshettiwar at Tata Institute of Fundamental Research (TIFR), Mumbai, has introduced a groundbreaking “plasmonic reduction catalyst stable in air.” This catalyst unites platinum-doped ruthenium clusters with “plasmonic black gold,” which efficiently captures visible light and creates numerous hot spots due to plasmonic coupling, boosting its catalytic performance.
Their work, described in a paper published in the journal Nature Communications, stands out due to its remarkable performance in the semi-hydrogenation of acetylene, an important industrial process. The catalyst achieved an ethene production rate of 320 mmol g−1 h−1 with around 90% selectivity, using only visible light illumination without external heating in the presence of excess ethene. This efficiency outperforms all known plasmonic and traditional thermal catalysts.
The catalyst’s unique requirement to perform best in the presence of air alongside the reactants provides unprecedented stability for at least 100 hours. The researchers attribute this to plasmon-mediated simultaneous reduction and oxidation processes at the active sites during the reaction.
Further investigation into this catalyst using finite-difference time-domain (FDTD) simulations revealed a five-fold increase in the electric field compared to pristine DPC. This field enhancement, resulting from near-field coupling between the RuPt nanoparticles and DPC, significantly contributes to activating chemical bonds. The catalyst’s effectiveness is also evident in its kinetic isotope effect (KIE), indicating the significant role of non-thermal effects alongside photothermal activation of the reactants. In-depth in-situ DRIFTS and DFT studies provided insights into the reaction mechanism over the oxide surface, particularly highlighting the role of intermediates in selectivity.
This research marks the first report of a highly efficient, air-stabilized, and plasmonically activated catalyst for acetylene semi-hydrogenation, with potential applications in a variety of other reduction reactions. The findings offer significant contributions to the understanding of plasmonic catalysis and pave the way for developing sustainable and energy-efficient catalytic systems.
More information:
Gunjan Sharma et al, Pt-doped Ru nanoparticles loaded on ‘black gold’ plasmonic nanoreactors as air stable reduction catalysts, Nature Communications (2024). DOI: 10.1038/s41467-024-44954-4
Journal information: Nature Communications
