Undoped and cerium doped Calcium sulfide (CaS) phosphors were synthesized using solid state diffusion method. The X-ray diffraction pattern revealed that both undoped and doped CaS crystallites have cubic structure with average crystallite size varying from 20 to 30 nm. Scanning electron micrographs indicated that Ce doped CaS phosphors were composed of whiskers with different dimensions and orientations. The optical properties of undoped and Ce doped particles were characterized using Photoluminescence (PL) and UV-Vis absorption spectroscopy. The PL emission spectrum of cerium doped CaS phosphors for an excitation wavelength 465 nm showed a main peak at 500 nm and a shoulder peak at 556 nm due to 5d → 4f transition in Ce ions. The variation of PL intensity with cerium concentration was investigated and the maximum PL intensity was obtained for a doping concentration of 3 wt.%. The optical band gap of the samples was estimated from the diffuse reflectance spectrum and was found to increase with increase in cerium concentration. The enhanced optical properties of these phosphors can be exploited in various optoelectronic devices including displays and bioimaging techniques.
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January 2025
State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin, 130022, China.
The scarcity of cost-effective and durable iridium-free anode electrocatalysts for the oxygen evolution reaction (OER) poses a significant challenge to the widespread application of the proton exchange membrane water electrolyzer (PEMWE). To address the electrochemical oxidation and dissolution issues of Ru-based electrocatalysts, an electron-donating modification strategy is developed to stabilize WRuO under harsh oxidative conditions. The optimized catalyst with a low Zirconium doping (Zr, 1 wt.
View Article and Find Full Text PDFAnal Chim Acta
February 2025
CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, PR China. Electronic address:
Dimethoate (DIM) is one of the most extensively applied organophosphorus pesticides (OPs), which is used to boost farm productivity due to its high insecticidal efficacy. However, the excessive use of DIM can result in the extensive contamination of soil, groundwater and food. Monitoring of DIM in environmental and food samples is crucial in view of its potential health risks and environmental hazards from excessive residues.
View Article and Find Full Text PDFEnviron Res
January 2025
Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; CAS Key Laboratory of Renewable Energy, Guangzhou 510640, China; Guangdong Provincial Key Laboratory of High-Quality Recycling of End-of-Life New Energy Devices, Guangzhou 510640, China. Electronic address:
Hydrogen sulfide (HS) is a major air pollutant posing a serious threat to both the environment and public health. In this study, a novel nitrogen-rich biocarbon that effectively removes HS was produced from a mixture of sewage sludge and pine sawdust using melamine as nitrogen source. Compared with pristine biocarbons, nitrogen (N)-doped biocarbons possessed an adjustable porosity, e.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
Tianjin University, School of Chemical Engineering and Technology, Weijin Road, 300072, Tianjin, CHINA.
Phosphoric acid (H3PO4) doping is a widely employed strategy to facilitate anhydrous proton transport in high-temperature proton exchange membrane fuel cells (HT-PEMFCs). However, significant H3PO4 leaching during long-term operation poses critical challenges to maintaining membrane stability and proton conductivity. Herein, H3PO4 is incorporated into positively charged nanochannels of quaternized covalent organic framework membranes (QACOFMs), leveraging strong electrostatic interactions and confinement effects to achieve exceptional H3PO4 retention under hydration conditions.
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
Key Laboratory of Precision and Intelligent Chemistry, School of Chemistry and Materials Science, CAS Key Laboratory of Materials for Energy Conversion, CAS Center for Excellence in Nanoscience, University of Science and Technology of China, Hefei, Anhui 230026, P.R. China.
Half-metallicity, enabling 100% spin polarization, is pivotal for spintronics but remains challenging to achieve in low-dimensional materials. Using first-principles calculations, we theoretically propose an experimentally feasible two-dimensional (2D) metal-organic framework (MOF) magnetic semiconductor, Cr(TCNB) (TCNB = 1,2,4,5-tetracyanobenzene). This monolayer can be exfoliated from a Ag(100) substrate due to its low exfoliation energy of 0.
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