Generation of efficient
light-induced charge separation inside
the photocatalyst is an essential factor for a high catalytic efficiency.
The usual immobilization of metal or metal oxide particles on semiconductor
photocatalysts offers an uncontrolled assembly of active sites during
the reaction. The introduction of single metal atoms on photocatalysts
can lead to extremely high atomic utilization and precise active sites.
However, this approach is limited because of the lack of suitable
photosensitizers for single atom immobilization. Here, we have designed
photocatalytic carbon quantum dots with anchoring sites for single
cobalt atoms in a defined Co–N4 structure via facile
pyrolysis of vitamin B12. Carbon dots functioned as both light-harvesting
antenna and support for the cobalt atom with high atom loadings up
to 3.27 wt %. This new photocatalytic material demonstrated enhanced
visible light absorption, efficient charge separation, and reduced
electrochemical impedance, while single Co atoms acted as the active
site with strong oxidative ability. As a result, the photocatalysts
showed excellent visible light-promoted photocatalytic efficiency
with oxygen evolution rates up to 168 μmol h–1 g–1 via water oxidation, imine formation with
high conversion (∼90%) and selectivity (>99%), and complete
photodegradation of organic dyes.
In this work, fluorescent carbon quantum dots (CQDs) composite transparent film with blue emission was prepared via hydrothermal fabrication, mixing with vinyl acetate-ethylene (VAE) emulsion, coated and cross-linked on the glass in sequence.This CQD/VAE film has good sticking ability and compatibility of sealing ethylenevinyl acetate (EVA) material and works well as luminescent downshifting (LDS) materials. Based on these features, we did a set of optical characteristics analysis for CQD/VAE film and inserted a CQD/VAE film between glass and EVA encapsulation in a mini metal wrap through (MWT) solar module. This LDS could convert UV part of solar spectra, which are normally blocked by EVA, into the blue range and improve the light absorption by solar cell. Enhancement in the performance of solar modules was proved, especially the improvement of current of short circuit (I sc ), external quantum efficiency (EQE) of the UV wavelength and solar module efficiency. This material provides the chance for prompt application, since it simply solves the dispersion problem of LDS material inside encapsulation and keeps the transparency of sealing polymer materials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.