Electron transfer from CdS quantum dots (QDs) to cobaloxime (Co(dmgH)2pyCl) is demonstrated by transient absorption spectroscopy (TAS), and further confirmed using photoluminescence (PL) techniques. The analysis of the PL quenching results offers a novel way to understand the roles of the surface adsorption sites of CdS QDs in the performance of charge transfer in the CdS QDs-cobaloxime hybrid system. Two types of quenching dynamics reveal that there are two different adsorption modes of cobaloxime on the CdS QD surface. When cobaloxime substitutes the surface capping ligands of CdS QDs under low cobaloxime concentrations, the transfer is nearly unfavorable for both the free and trapped electrons. When cobaloxime occupies the surface defect sites of the CdS QDs under high cobaloxime concentrations, the transfer of both the free and trapped electrons is very effective, with an extremely high quenching rate constant of ∼10(12) M(-1) s(-1). Therefore, controlling the molecular adsorption sites and adjusting the surface defect properties of semiconductor QDs provide a strategy to improve the electron transfer efficiency of the QDs-cobaloxime photocatalytic system.
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http://dx.doi.org/10.1039/c6cp02808j | DOI Listing |
RSC Adv
January 2025
Laboratory of Clean Low-Carbon Energy, Department of Thermal Science and Energy Engineering, University of Science and Technology of China Hefei 230023 PR China.
Crafting highly dispersed active metal sites on catalysts is an optimal method for improving the catalytic reactivity and stability, as it would improve atomic utilization efficiency, enhance reactant adsorption and activation ability through unique geometric and electronic properties. In this study, two synthesis methods were employed (ammonia evaporation (AE) and the impregnation method (IM)) to load Rh species onto the ZSM-5 support in order to attain tunable dispersivity, during which a 1.25-fold increase in the total yield of liquid oxygenated products (32 433.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu 610064, P. R. China.
As an efficient, sustainable, and environmentally friendly semiconductor material, covalent organic frameworks (COFs) can generate hydrogen peroxide (HO) by photocatalysis, attracting wide attention in recent years. Herein, the effects of hydroxyl, methoxyl, and vinyl groups of imide-linked two-dimensional (2D) COFs on the photocatalytic production of HO were studied theoretically and experimentally. The introduction of vinyl groups greatly promotes the photogenerated charge separation and migration of COFs, providing more oxygen adsorption sites, stronger proton affinity, and lower intermediate binding energy, which effectively facilitates the rapid conversion of oxygen to HO.
View Article and Find Full Text PDFAcc Chem Res
January 2025
Key Lab of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310027, China.
ConspectusFor chemical reactions with complex pathways, it is extremely difficult to adjust the catalytic performance. The previous strategies on this issue mainly focused on modifying the fine structures of the catalysts, including optimization of the geometric/electronic structure of the metal nanoparticles (NPs), regulation of the chemical composition/morphology of the supports, and/or adjustment of the metal-support interactions to modulate the reaction kinetics on the catalyst surface. Although significant advances have been achieved, the catalytic performance is still unsatisfactory.
View Article and Find Full Text PDFEnviron Res
January 2025
College of Energy and Electrical Engineering, Qinghai University, Xining, Qinghai, 810016, China; CHN Energy group Qinghai Electric Power Co., LTD, Xining, Qinghai, 810008, China. Electronic address:
This research using the first-principles theory introduces Pd- and Pt-functionalized WSe monolayers as promising materials for detecting three critical gases (H, CO, and CH), to evaluate the health of Li-ion battery (LIBs). Various sites on the pristine WSe monolayer are considered for the functionalization with Pd and Pt atoms. The adsorption performances of the determined Pd- and Pt-WSe monolayers upon the three gases are analyzed by the comparative highlight of the adsorption energy, bonding behavior and electron transfer.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Department of Energy and Materials Engineering, Dongguk University-Seoul, Seoul 04620, Republic of Korea. Electronic address:
The presence of cobalt ions (Co) and radionuclides (Co) in industrial and radioactive effluents pose serious threats to environmental ecosystems and human health. This paper presents the synthesis of dual-functional hydroxyapatite (HAp)-incorporated spherical carbon (SC) composite (HAp/SC) towards the selective adsorption of cobalt from wastewater and the utilization of the Co-adsorbed HAp/SC composite (Co- HAp/SC) as an electrocatalyst for the oxygen evolution reaction (OER). Herein, we prepared a series of HAp/SC composites by varying HAp weight percentages of 10 %, 20 %, 30 %, 40 %, and 50 %.
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