SrAl2O4:Eu2+,Dy3+ long afterglow phosphors with one-dimensional nanostructures were synthesized by a hydrothermal method followed by post-annealing, and subsequently CdS was uniformly coated on their surfaces by a sol-gel approach. The nanocomposite system can significantly enhance the photocatalytic activity for the degradation of methyl orange and hexavalent chromium under ultraviolet and visible light irradiation. After the modification treatment with a 1 : 2 molar ratio of CdS to SrAl2O4:Eu2+,Dy3+ nanophosphors, the degradation rate of methyl orange can increase by 2.5 times and reach a maximum of 96.3% under visible light illumination for 30 min. The enhancement of photocatalytic activity originates from the improvement of light usage efficiency due to the hole migration from SrAl2O4:Eu2+,Dy3+ phosphors to the CdS semiconductor and the reutilization of SrAl2O4:Eu2+,Dy3+ luminescence.
The photoreduction of carbon dioxide (CO2) to valuable fuels is a promising strategy for the prevention of rising atmospheric levels of CO2 and the depletion of fossil fuel reserves. However, most reported photocatalysts are only active in the ultraviolet region, which necessitates co-catalysts and sacrificial agents in the reaction systems, leading to an unsatisfied economy of the process in energy and atoms. In this research, a CuMoxW(1-x)O4 solid solution was synthesized, characterized, and tested for the photocatalytic reduction of CO2 in the presence of amines. The results revealed that the yield of CH3OH from CO2 was 1017.7 μmol/g under 24 h visible light irradiation using CuW0.7Mo0.3O4 (x = 0.7) as the catalyst. This was associated with the maximum conversion (82.1%) of benzylamine to N-benzylidene benzylamine with high selectivity (>99%). These results give new insight into the photocatalytic reduction of CO2 for valuable chemical products in an economic way.
Here,
CdS@C nanohybrid composites, where CdS quantum dots (QDs)
are uniformly embedded in carbon micro-/nanobelt matrixes, are synthesized
via a combustion synthesis followed by a postvulcanization. In the
nanohybrids, trap centers are effectively created by the introduction
of QDs and moreover their barrier height and filling level can be
effectively modulated through a coupling of externally loaded strain
and bias. Thus, a single CdS@C micro-/nanobelt-based two-terminal
device can exhibit an ultrahigh real-time response to compressive
and tensile strains with a tremendous gauge factor of above 104, high sensitivity, and fast response and recovery. More importantly,
the trapped charges can be mechanically excited by stress, and furthermore,
the stress-triggered high-resistance state can be well-maintained
at room temperature and a relatively low operation bias. However,
it can be back to its initial low resistance state by loading a relatively
large bias, showing a superior erasable stress memory function with
a window of about 103. By an effective construction of
trap centers in hybrid composites, not only can an ultrahigh performance
of volatile real-time stress sensor be obtained under the synergism
of external stress and electric field but also can an outstanding
erasable nonvolatile stress memory be successfully realized.
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.