Probing the Advantageous Photosensitization Effect of Metal Nanoclusters over Plasmonic Metal Nanocrystals in Photoelectrochemical Water Splitting

Abstract

Atomically precise metal nanoclusters (NCs)-based photocatalytic systems have garnered enormous attention owing to the fascinating merits including unique physicochemical properties, quantum confinement effect, and photosensitization effect, which are distinct from conventional metal nanocrystals (NYs). Nevertheless, a systematic comparison between electrons photoexcited from metal NCs and hot electrons from surface plasmonic resonance (SPR) effect of metal NYs in boosting photoelectrochemical water splitting reaction remains blank. Here, we report the strict and comprehensive comparison on the capability of electrons photoexcited from glutathione-capped gold nanoclusters (Au x @GSH) and hot electrons from plasmonic excitation of gold nanoparticles (Au NYs) self-transformed from Au x @GSH to trigger the photoelectrochemical (PEC) water splitting reaction under visible light irradiation. The results indicate that photoelectrons of Au x NCs trigger a more efficient charge transport rate than hot electrons of plasmonic Au NYs in terms of light-harvesting and conversion efficiency under identical conditions. Moreover, charge transfer characteristics in Au x NC- and Au NY-based PEC systems were established. This work would reinforce our deep understanding of these two pivotal sectors of metal nanomaterials for solar energy conversion.

Tuning atomically precise metal nanocluster mediated photoelectrocatalysis via a non-conjugated polymer

“…42 In the FTIR spectrum of T(PA) 4 , the peak at 1642 cm −1 demonstrates a more substantial intensity than that in the spectrum of the TNRAs due to the overlapping vibration modes of the –OH and –CO groups from the GSH ligand, 43 and the enhanced peak at 3440 cm −1 was assigned to the fingerprint stretching vibration mode of the surface –OH groups. The FTIR spectrum of T(PA) 4 exhibits a new peak at 1110 cm −1 corresponding to the C–N bending vibration mode of the GSH ligand, 44 which is not observed in the FTIR spectrum of the TNRAs. The differences between the FTIR spectra of T(PA) 4 and the TNRAs implied that the Ag x NCs and PDDA had been successfully deposited on the TNRA substrate via LbL assembly.…”

“…S5c,† the new peak at 287.92 eV corresponds to the carboxyl (–COOH) groups from the GSH ligand of the Ag x NCs. 44 Fig. 1l exhibits two peaks at 374 eV (Ag 3d 5/2 ) and 368 eV (Ag 3d 3/2 ) in the high-resolution Ag 3d spectrum of T(PA) 4 , wherein each peak demonstrates two valence states of metallic Ag(0) and Ag( i ), stemming from the Ag(0)/Ag( i ) core–shell structure of the Ag x NCs.…”

Plasmonic Metal Nanostructures as Efficient Light Absorbers for Solar Water Splitting

“…It was then found that Au NCs had a stronger interfacial charge transfer capability and a higher current density under visible light irradiation than Au NYs, due to the efficient photoelectrons excited from Au x NCs. [27] Kim et al fabricated Au nanodot arrays with controllable sizes (50, 63, 83 nm) using a direct contact printing method and found that the generated plasmonic enhancement for PEC water splitting reaction increased with decreasing Au particle size (Figure 5a-c). [28] For the TiO 2 -coated 50 nm Au nanodots sample, the photocurrent density (about 4 μA cm À2 ) and the gas production (about 6.5 μmol h À1 ) reached the maximum values.…”

Bridging from Metallic Nanoclusters to Biomedical in Understanding Physicochemical Interactions at the Nano–Bio Interface

“…NCs can harvest light in the visible range and generate efficient hole and electron, so these properties make them a good catalyst. [4,24,31] Enzyme like activity. After photoinduction and charge separation, each one of LUMO electrons and HOMO holes migrate to the NC surface and promote reduction or oxidation catalytic activity.…”

“…Among fluorophores, NCs have great photostability, biocompatibility, and low toxicity, although they have quantum yield typically lower than 20%; and therefore hold great promise for use in cell labeling and bioimaging. [5,9,24] Researchers have done many studies on in vitro cell imaging using NCs (Figure 3A). In vivo imaging is a very influential method for tracking of target biomolecules in living systems (Figure 3B).…”