Enhanced interfacial charge transfer and photothermal effect via in-situ construction of atom co-sharing Bi plasmonic/Bi4O5Br2 nanosheet heterojunction towards improved full-spectrum photocatalysis

Generation of •OH and •O2– Radicals by a Bi2O3-Nanoparticle/Bi4O5Br2 Type-II Heterojunction for Photocatalytic Degradation of Organic Molecules

“…The ESR signals of BOB4 in Figure c display four peaks with intensity ratios of 1:2:2:1, which are typical characteristics of the DMPO- • OH adduct, but there is no signal of the DMPO- • OH adduct for Bi 4 O 5 Br 2 , indicating generation of • OH for BOB4. This observation implies that the generation of • OH is facilitated, potentially due to an increased availability of h + for interfacial reactions in the composite . The result of ESR spectra of TEMPO-h + proved this point (Figure d).…”

“…The enhancement of photoactivity may be attributed to the increased production of radicals • O 2 – and • OH by these binary composites. The CB level of Bi 4 O 5 Br 2 is more negative than the redox potential of O 2 (−0.33 eV vs NHE), , allowing the e – on the CB of Bi 4 O 5 Br 2 to react with the O 2 adsorbed on the catalyst’s surface, resulting in the generation of • O 2 – radical species. Additionally, both Bi 4 O 5 Br 2 and Bi 2 O 3 have VB levels higher than the potential of OH – / • OH (1.99 eV vs NHE), , enabling the enriched holes (h + ) on the VB of Bi 2 O 3 to react with OH – and generate • OH radicals.…”

“…ESR was further performed to verify the roles of • O 2 − , h + , and • OH in the photocatalytic reactions. 18,51 As shown in Figure 8c, the ESR spectra (Figure 8c) of both Bi 4 O 5 Br 2 and BOB4 show characteristic peaks corresponding to the DMPO-• O 2 − species. Furthermore, the ESR signal of BOB4 is observed to be stronger than that of Bi 4 O 5 Br 2 , suggesting a faster generation of • O 2 − for BOB4.…”

“…This observation implies that the generation of • OH is facilitated, potentially due to an increased availability of h + for interfacial reactions in the composite. 51 The result of ESR spectra of TEMPO-h + proved this point (Figure 8d). Compared with Bi 4 O 5 Br 2 , the ESR peak intensity of TEMPO in BOB4 is found to decrease, suggesting a higher production of h + by BOB4 during the photocatalytic reaction.…”

Recent Progress on Photocatalytic CO2 Conversion Reactions over Plasmonic Metal-based Catalysts

“…It has been reported that plasmonic metal-based photocatalysts displayed strong light absorption ability in visible or near-infrared light range, which means that it is easier to adjust or enlarge their light response range to infrared light range compare to conventional semiconductors-based photocatalysts. Besides, the abundant Al and cheap transition metal oxides, which could harness infrared light, might be adopted as components of photocatalysts for harvesting infrared light and improving light utilization efficiency. , Therefore, future studies should pay much attention to these materials so that the photocatalytic CO 2 conversion activity can be improved. The selectivity of the product is relatively low, which is far from industrial production. Owing to the diversity of products from CO 2 conversion and possible competition reactions (e.g., water splitting during CO 2 photoreduction with H 2 O), it is difficult to make sure a stable selectivity over photocatalytic systems.…”