Efficient Harvesting of >1000 nm Photons to Hydrogen via Plasmon-Driven Si–H Activation in Water

Abstract

Efficient harvesting of the near-infrared (NIR) portion of the sunlight remains key to the development of a solar-to-fuel renewable energy infrastructure. Here we report on the development of first pristine plasmonic nanoparticle-assisted NIR-II photon-to-hydrogen production strategy that does not require any external electric bias or sacrificial chemicals. Our strategy utilizes a robust and easily scalable plasmonic substrate containing pristine gold nanoprisms to drive photocatalytic Si–H activation in water, producing hydrogen and silanol. The photocatalytic substrate exhibited excellent photon-to-hydrogen conversion efficiency of ∼0.85–1.45% for wavelengths between 1000 and 1700 nm while producing hydrogen at 132 μL min–1 mg–1 Au. The robustness and easy scalability of our catalyst fabrication, ease of usage, excellent photon-to-hydrogen production efficiency, and no requirement of additional energy bias make our strategy highly relevant for applications in the alternative energy sector.

Ligand-mediated electron transport channels enhance photocatalytic activity of plasmonic nanoparticles

“…This wavelength range was selected as the associated photons would not have energy for water splitting but could drive a photothermal Si–H activation, as demonstrated previously. 69 We also did not see any hydrogen formation in this study, confirming that Si–H activation is not the source of hydrogen. Furthermore, simultaneous measurement of oxygen reveals that hydrogen and oxygen are being produced at a ratio of 1.9 : 1, which is very close to what one would expect from a water splitting reaction (Fig.…”

Hot Electrons in Catalysis

“…Sarhan et al show that broadband absorption of colloidal black Au NPs enables hot-electron-driven dimerization and cross-linking of 4-nitrothiophenol. Kumar et al show that near-infrared (NIR) light excitation of NIR-resonant triangular Au nanoprisms induces the hydrolysis of dimethylphenylsilane but likely does so via a photothermal effect rather than photochemical enhancement. Zang et al show that photoelectrochemical water splitting can be enhanced by strong coupling of localized surface plasmon resonances (LSPRs) with a Fabry–Pérot nanocavity.…”