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One of the most pressing challenges in single‐atom catalysis is the manipulation of the coordination environment of central metals to maximize the catalyst performance. Herein, we fabricated a high‐performance catalyst (Co‐SNC) by introducing S into the neighboring position of the Co‐N4 coordination. The developed ball‐milling method enabled large‐scale synthesis, that over 4.7 g of Co‐SNC can be produced in one pot. In benzylamine coupling reaction, Co‐SNC exhibited the highest conversion of 97.5 % with 99 % selectivity toward N‐benzylidenebenzylamine in 10 h among various Co catalysts. Density functional theory calculations revealed the crucial role of S atoms, which serve as the active sites for O2 activation, leaving the Co atoms free to adsorb benzylamine. Consequently, the adsorption energies of O2 and benzylamine were significantly increased. Our strategy suggests a feasible approach to enhance catalytic performance by delicately integrating dual active sites into a single catalyst unit.

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In this paper, multifunctional inorganic−organic nanocomposites were fabricated through encapsulating CdTe quantum dots and Rhodamine 6G-deprived receptor into the nonporous and mesoporous shell of the magnetic mesoporous silica nanocomposites. The resultant nanomaterials display an obvious core−shell structure, superparamagnetic property, ordered mesoporous characteristics, and highly selective, sensitive, and regenerative ratiometric fluorescent sensing performance for determination of Hg 2+ . A good linearity is obtained between I Rh6G /I QDs and Hg 2+ concentration (0.7 to 90 × 10 −8 mol•L −1 ), exhibiting a detection limit as low as 2.5 × 10 −9 mol•L −1 . Moreover, the multifunctional nanocomposites possess acceptable Hg 2+ adsorption capacity and can be simply separated by magnet. Real water sample assays further verified its good mercury ion analysis and removal ability. Our results reveal that high sensitivity, selectivity, rapid adsorption, efficient removal ability, and good reusability as well as better accuracy can be simultaneously achieved by combining magnetic mesoporous silica nanocomposite with ratiometric fluorescence sensing properties than the traditional intensity-based fluorescence methods. This recyclable multifunctional hybrid nanostructure may have great potential for Hg 2+ detection and removal in environmental, biological, and toxicological areas.

A ternary nanocomposite of ZnMoNCs containing ZnO, ZnS and MoS2 has been synthesized by a facile strategy derived from polyoxometalate and ZIF-8, which shows high SERS activity by increased adsorption sites and synergistically improved charge transfer.