Harnessing Vis–NIR broad spectrum for photocatalytic CO2 reduction over carbon quantum dots-decorated ultrathin Bi2WO6 nanosheets

Carbon Dots: Bottom‐Up Syntheses, Properties, and Light‐Harvesting Applications

“…Interestingly, CDs can act as a spectral converter as well as a harvester for efficient photocatalytic activity over a broad spectral range, from visible to NIR irradiation. For example, CDs synthesized from citric acid/Bi 2 WO 6 nanosheets have been developed for CO 2 photoreduction under visible/NIR light (Figure b) . This composite exhibited excellent catalytic properties under visible (>400 nm) and even NIR (>700 nm) light because of the enhanced light absorption with the redshifting of the band edge.…”

“…thesized from citric acid/Bi 2 WO 6 nanosheets have been developed for CO 2 photoreduction under visible/NIR light (Figure 6b). [53] This composite exhibited excellent catalytic properties under visible (> 400 nm) and even NIR (> 700 nm) light because of the enhanced light absorption with the redshifting of the band edge.…”

“…b) Schematici llustration of photocatalytic CO 2 reduction over CD/Bi 2 WO 6 hybridn anocompositesu nder visible-a nd NIR-light irradiation. Reprinted with permission from Ref [53]…”

Bismuth‐Based Photocatalysts for Solar Photocatalytic Carbon Dioxide Conversion

“…It is knownt hat dye sensitization, the SPR effect of noble metals, and carbon materials are excellent ways to improve the lightharvesting efficiency.F or example, CQD-decorated ultrathin Bi 2 WO 6 nanosheets (UBW) were demonstrated to be an efficient photocatalyst for CO 2 photoreduction over the broad Vis-NIR spectrum (Figure20). [167] Under visible-light irradiation, optimized 1CQDs/UBW (1 wt %C QD) exhibited ar emarkable 3.1-fold enhancement of CH 4 production compared with that of bare UBW.M ore importantly,t he photocatalytic responsive- ness of CQDs/UBW was successfully extended to the NIR region, which was achieved withoutinvolving any rare-earth or noble metals.I na ddition to light harvesting, the authors also summarized other reasonsf or effective NIR-driven CO 2 reduction, such as the high exposure rate of {001} active facets of UBW and the cocatalyst nature of the CQDs for enhancing the carrier separation efficiency.…”

“…Due to the unique structure, Bi 2 WO 6 hollow HMSs possess higher CO 2 adsorption capacityt han that of bulk Bi 2 WO 6 .T his indicates that the hollow hierarchicals tructure plays an important role in enhancing the CO 2 adsorption capacity.I na ddition, FTIR spectra of Bi 2 WO 6 were recorded before and after CO 2 photoreduction, revealing two bands (ñ = 1146 and 1200cm À1 )t hat appeared after CO 2 photoreduction and were attributedt othe stretching vibration of ÀCÀOH groups. [167] Under visible-light irradiation, optimized 1CQDs/UBW (1 wt %C QD) exhibited ar emarkable 3.1-fold enhancement of CH 4 production compared with that of bare UBW.M ore importantly,t he photocatalytic responsive- www.chemsuschem.org ness of CQDs/UBW was successfully extended to the NIR region, which was achieved withoutinvolving any rare-earth or noble metals.I na ddition to light harvesting, the authors also summarized other reasonsf or effective NIR-driven CO 2 reduction, such as the high exposure rate of {001} active facets of UBW and the cocatalyst nature of the CQDs for enhancing the carrier separation efficiency. The authorss uggested that photoinduced chargetransfer took place,a nd the formed photoexcited W V centers were responsible for the multiple-electron reduction of CO 2 to methanol.…”