Atomically precise metal nanoclusters(MNCs)have emerged as tailorable luminescent materials with visible to near-infrared emission modulated by core(kernel)size,metal composition,and ligand engineering.These ultrasmal...Atomically precise metal nanoclusters(MNCs)have emerged as tailorable luminescent materials with visible to near-infrared emission modulated by core(kernel)size,metal composition,and ligand engineering.These ultrasmall clusters exhibit discrete quantum-confined electronic states with strong spin-orbit coupling(SOC),enabling diverse emission pathways.Current research focuses on elucidating emission mechanisms and developing strategies to enhance fluorescence quantum yields.In this review,we emphasize structure-photoluminescence(PL)correlations and the underlying excited-state origins of luminescence:(i)coinage-metal clusters display multiple emissive channels-including prompt fluorescence,room-temperature phosphorescence,and TADF;(ii)the electronic gap and thus emission energy is directly governed by core size and metal identity,with core shrinkage and enhanced SOC generally inducing red-shifts;and(iii)ligand shell properties(identity/rigidity/packing)control charge-transfer pathways and nonradiative decay,while heterometal doping or rigidification modulates state ordering to brighten emission without necessarily shifting band positions.Importantly,many clusters exhibit dual-emission behavior.We propose a coupled core-shell emissive-state model in which one band originates from metal-core excitation and the other from a ligand-or motif-centered charge-transfer state.Finally,we outline future challenges:dissecting core versus shell contributions to PL and boosting quantum efficiency through targeted control of cluster composition and ligand shell.Progress on these fronts is crucial for the rational design of next-generation cluster emitters.展开更多
Photocatalytic oxidation coupling of amines represents a green and cost-effective method for the synthesis of highly value-added imines under visible light irradiation.However,the catalytic efficiency was severely lim...Photocatalytic oxidation coupling of amines represents a green and cost-effective method for the synthesis of highly value-added imines under visible light irradiation.However,the catalytic efficiency was severely limited by poor visible light response and easy recombination of photogenerated charge carriers.Herein,we report a g-CgN_(4)/α-Bi_(2)O_(3)Z-scheme heterojunction via electrostatic self-assembly of g-C_(3)N_(4)nanosheets and oxygen-va-cancy-rich aα-Bi_(2)O_(3)microsphere for visible-light driven oxidative coupling of amines to imines in H_(2)0 as green solvent at room temperature.Amines with diverse functional groups were efficiently converted into the corre-sponding imines in good to excellent yields.Impressively,this photocatalytic protocol is applicable for the challenging hetero-coupling of two structurally different amines to construct complicated asymmetric imines,which is the first report of photocatalytic hetero-coupling of amines to imines to our knowledge.Furthermore,the Z-scheme heterojunction also demonstrated high stability and could be readily separated and reused without obvious decay in activity and selectivity.Comprehensive characterizations and control experiments reveal the construction of Z-scheme heterojunction with intimate interface between g-CgN4 and a-Bi_(2)O_(3)greatly boosts the transfer and separation of photogenerated charge carries and enhances the redox capability.Meanwhile,the surface oxygen vacancies in a-Biz_(2)O_(3)also benefits the separation of photogenerated charge carriers and acti-vation of reactants.These jointly contributed to an enhanced photocatalytic performance for oxidative coupling of amines to imines.展开更多
基金the financial support provided by the National Natural Science Foundation of China(22571175,22171156,and 21803001)Scientific Research Innovation Capability Support Project for Young Fac-ulty(SRICSPYF-BS2025055)+1 种基金Taishan Scholar Foundation of Shandong Province(China)Shandong Province Excellent Youth Innovation Team and Startup Funds from Qingdao University of Science and Technology.
文摘Atomically precise metal nanoclusters(MNCs)have emerged as tailorable luminescent materials with visible to near-infrared emission modulated by core(kernel)size,metal composition,and ligand engineering.These ultrasmall clusters exhibit discrete quantum-confined electronic states with strong spin-orbit coupling(SOC),enabling diverse emission pathways.Current research focuses on elucidating emission mechanisms and developing strategies to enhance fluorescence quantum yields.In this review,we emphasize structure-photoluminescence(PL)correlations and the underlying excited-state origins of luminescence:(i)coinage-metal clusters display multiple emissive channels-including prompt fluorescence,room-temperature phosphorescence,and TADF;(ii)the electronic gap and thus emission energy is directly governed by core size and metal identity,with core shrinkage and enhanced SOC generally inducing red-shifts;and(iii)ligand shell properties(identity/rigidity/packing)control charge-transfer pathways and nonradiative decay,while heterometal doping or rigidification modulates state ordering to brighten emission without necessarily shifting band positions.Importantly,many clusters exhibit dual-emission behavior.We propose a coupled core-shell emissive-state model in which one band originates from metal-core excitation and the other from a ligand-or motif-centered charge-transfer state.Finally,we outline future challenges:dissecting core versus shell contributions to PL and boosting quantum efficiency through targeted control of cluster composition and ligand shell.Progress on these fronts is crucial for the rational design of next-generation cluster emitters.
基金supported by the National Natural Science Foundation of China(No.22078350)the Natural Science Foundation of Shandong Province(ZR2020KB016)Shandong Energy Institute Fund(Grant no.SEII202138).
文摘Photocatalytic oxidation coupling of amines represents a green and cost-effective method for the synthesis of highly value-added imines under visible light irradiation.However,the catalytic efficiency was severely limited by poor visible light response and easy recombination of photogenerated charge carriers.Herein,we report a g-CgN_(4)/α-Bi_(2)O_(3)Z-scheme heterojunction via electrostatic self-assembly of g-C_(3)N_(4)nanosheets and oxygen-va-cancy-rich aα-Bi_(2)O_(3)microsphere for visible-light driven oxidative coupling of amines to imines in H_(2)0 as green solvent at room temperature.Amines with diverse functional groups were efficiently converted into the corre-sponding imines in good to excellent yields.Impressively,this photocatalytic protocol is applicable for the challenging hetero-coupling of two structurally different amines to construct complicated asymmetric imines,which is the first report of photocatalytic hetero-coupling of amines to imines to our knowledge.Furthermore,the Z-scheme heterojunction also demonstrated high stability and could be readily separated and reused without obvious decay in activity and selectivity.Comprehensive characterizations and control experiments reveal the construction of Z-scheme heterojunction with intimate interface between g-CgN4 and a-Bi_(2)O_(3)greatly boosts the transfer and separation of photogenerated charge carries and enhances the redox capability.Meanwhile,the surface oxygen vacancies in a-Biz_(2)O_(3)also benefits the separation of photogenerated charge carriers and acti-vation of reactants.These jointly contributed to an enhanced photocatalytic performance for oxidative coupling of amines to imines.
