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It is not resolved which model describes better the aqueous-phase nucleation and growth of semiconductor quantum dots (QDs), the classical one-step one or the nonclassical multi-step one. Here, we design a room-temperature reaction to trap reaction intermediates in the prenucleation stage of ZnSe QDs (as a model system). We show that the trapped intermediate can transform to magic-size clusters (MSCs) via intra-molecular reorganization and can fragment to enable the growth of QDs. The MSCs exhibit a sharp optical absorption peaking at 299 nm, labelled MSC-299. The intermediate, the precursor compound (PC-299) of MSC-299, is optically transparent at 299 nm and to longer wavelengths. This intermediate forms in various Zn and Se reaction systems. The present study provides unambiguous evidence that the nonclassical and classical pathways are both necessary to explain the nucleation and growth of aqueous-phase QDs, with the former pathway favored more by high reaction concentrations.
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http://dx.doi.org/10.1002/anie.202209615 | DOI Listing |
J Phys Chem A
September 2025
Department of Chemistry, Tsinghua University, Beijing 100084, China.
A series of Cu-based single-atom catalysts (SACs) with asymmetric coordination were designed to accelerate lithium-sulfur (Li-S) chemistry. The electronegativity contrast from the dopant induces a localized electronic asymmetry that amplifies Jahn-Teller distortion at the Cu center. This distortion profoundly modulates the Cu 3d electronic structure and its interaction with Li-S intermediates.
View Article and Find Full Text PDFDiscov Nano
September 2025
Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, 30013, Taiwan.
Promoter-assisted chemical vapor deposition (CVD) has emerged as a robust strategy for the low-temperature synthesis of diverse transition metal dichalcogenides (TMDs). In these processes, promoter-induced intermediates facilitate specific reaction pathways, enabling controlled growth via vapor-solid-solid (VSS) or vapor-liquid-solid (VLS) modes. While previous studies have primarily focused on transition metal precursors, growth pathways involving engineered chalcogen-based intermediates remain underexplored due to their volatility and low melting points.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health, Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control, Institute of Environmental Health and Pollution Control, Guangdong University of Technology, Guangzhou 510006, China.
Low molecular weight amines promote sulfate (SO and HSO) formation through acid-base reactions, contributing to fine particulate matter (PM). Heterogeneous ozonation converts nontoxic amine salts into highly toxic products, yet the ozonation activation mechanism is unclear. This work reveals a sulfate-dominant ozonation mechanism of amine salts in fine PM by combining advanced mass spectrometry and ab initio calculation methods.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
State Key Laboratory of Antiviral Drugs, Tianjian Laboratory of Advanced Biomedical Sciences, Pingyuan Laboratory, and College of Chemistry, Zhengzhou University, Zhengzhou 450001, China.
The C-H functionalization represents a universal and important method for constructing new C-C bonds by carrying out reactions directly on inert C-H bonds. The major challenges are to control the site-selectivity and chemoselectivity because most complex organic compounds have many similar C-H bonds or different functional groups, such as a C═C bond or O-H bond. Here, we develop a versatile copper cluster (CuNC) with high stability and dynamic catalytic sites.
View Article and Find Full Text PDFSmall
September 2025
School of Chemistry and Chemical Engineering, Guangxi Key Laboratory of AI-Driven Zero-Carbon Technologies, Key Laboratory of New Low-carbon Green Chemical Technology Education Department of Guangxi Zhuang Autonomous Region, Guangxi University, Nanning, 530004, China.
Sarcosine (Sar), a critical potential biomarker for prostate cancer (PCa), is primarily detected via enzyme cascade reactions involving sarcosine oxidase (SOx) and peroxidase. Nevertheless, the intermediate product hydrogen peroxide (HO) tends to diffuse to the bulk solution phase without entering subsequent reaction, leading to suboptimal detection sensitivity and compromised analytical performance. To tackle this challenge, a multilayered sandwich nanozyme cascade sensor (designated as Cu-MOF/Rf@BDC) is proposed through a confinement-mediated HO enrichment strategy.
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