Efficient Near-Infrared-Activated Photocatalytic Hydrogen Evolution from Ammonia Borane with Core-Shell Upconversion-Semiconductor Hybrid Nanostructures

Abstract

In this work, the photocatalytic hydrogen evolution from ammonia borane under near-infrared laser irradiation at ambient temperature was demonstrated by using the novel core-shell upconversion-semiconductor hybrid nanostructures (NaGdF4:Yb3+/Er3+@NaGdF4@Cu2O). The particles were successfully synthesized in a final concentration of 10 mg/mL. The particles were characterized via high resolution transmission electron microscopy (HRTEM), photoluminescence, energy dispersive X-ray analysis (EDAX), and powder X-ray diffraction. The near-infrared-driven photocatalytic activities of such hybrid nanoparticles are remarkably higher than that with bare upconversion nanoparticles (UCNPs) under the same irradiation. The upconverted photoluminescence of UCNPs efficiently reabsorbed by Cu2O promotes the charge separation in the semiconducting shell, and facilitates the formation of photoinduced electrons and hydroxyl radicals generated via the reaction between H2O and holes. Both serve as reactive species on the dissociation of the weak B-N bond in an aqueous medium, to produce hydrogen under near-infrared excitation, resulting in enhanced photocatalytic activities. The photocatalyst of NaGdF4:Yb3+/Er3+@NaGdF4@Cu2O (UCNPs@Cu2O) suffered no loss of efficacy after several cycles. This work sheds light on the rational design of near-infrared-activated photocatalysts, and can be used as a proof-of-concept for on-board hydrogen generation from ammonia borane under near-infrared illumination, with the aim of green energy suppliers.

Visible Light-Promoted Enhanced Photocatalytic Hydrogen Generation by the CeF3:Ho3+-Incorporated TiO2 Nanosystem

“…The H 2 generation activity of Er/Yb-doped TiO 2 was observed to be boosted (10.05 μmol h −1 ) by plasmonic MoO 3−x . Recently, Jing et al 38 have reported a novel core−shell approach to synthesizing a nanostructure comprising NaGd-F 4 :Yb 3+ /Er 3+ @NaGdF 4 @Cu 2 O. The same was examined for its ability to photocatalytically convert ammonia borane (AB) to H 2 (33 μmol h −1 ).…”

Efficient Hydrogen Evolution Reaction with Bulk and Nanostructured Mitrofanovite Pt3Te4

“…In this context, hydrogen could play a key role in the future of energy devices and their related implications for economy [ 4 , 5 , 6 , 7 ]. Hydrogen is the most abundant light element of the universe.…”