Ligand engineering for well-defined gold nanoclusters(Au NCs) is getting more extensive attention. Organizing the Au-ligand interfaces on gold NCs can achieve the structural and functional control. This review focuses...Ligand engineering for well-defined gold nanoclusters(Au NCs) is getting more extensive attention. Organizing the Au-ligand interfaces on gold NCs can achieve the structural and functional control. This review focuses on the Au-ligand interfaces including gold-phosphorus(Au-P), gold-sulfur(Au-S), gold-selenium(Au-Se), gold-carbon(Au-C), and gold-nitrogen(Au-N), derived from the bonding between Au atoms and the different ligands(e.g., organic phosphine, thiolate, selenolate, alkynyl,n-heterocyclic carbene and nitrogenous ligands). The formation mechanism of Au-ligand interfaces is well discussed. In addition, the effects of Au-ligand interfaces on the stability, optical property, and catalysis are also presented. We hope the advances in this research area can boost the development of Au NC sciences.展开更多
Atomically precise water-soluble gold nanoclusters(Au NCs)protected by organic ligands have attracted growing attention in serving as unique nanomaterials with the potential to generate theranostic tools(bioimaging,bi...Atomically precise water-soluble gold nanoclusters(Au NCs)protected by organic ligands have attracted growing attention in serving as unique nanomaterials with the potential to generate theranostic tools(bioimaging,biosensing,and biotherapy),due to their ultrasmall size,superior photoluminescence,good biocompatibility,and nontoxicity.More importantly,Au NCs afford a well-defined atomic packing structure and molecular purity,providing a superior platform to unravel the structure−performance correlations for biodistribution,biological pharmacokinetics,and excretion of Au NCs.In this Review,we mainly survey the synthesis of water-soluble Au NCs and the recent progress in biomedicine of Au NCs,including bioimaging,biosensing,and biotherapy.The effects of ligand and size on the biomedical properties are discussed in detail.We hope that the advances in this research area can expand the applications of Au NCs in biomedicine.展开更多
Internal diffusion of molecules in porous materials plays an important role in many chemical processes.However, the pore diffusion capacity of porous materials cannot be measured by conventional catalyst characterizat...Internal diffusion of molecules in porous materials plays an important role in many chemical processes.However, the pore diffusion capacity of porous materials cannot be measured by conventional catalyst characterization methods. In the present paper, a pore diffusion factor, the ratio of the diffusionconstriction factor to the pore tortuosity of the porous materials, was proposed to measure the diffusion ability of pores inside solid materials, and a method was proposed for measuring the diffusion factor using a well-defined and uniform pore size material as a reference. The diffusion factor was calculated based on the effective diffusion coefficients and the diffusion-constriction factor and pore tortuosity of the reference porous materials. The pore diffusion factor measurement can be performed at room temperature and atmospheric pressure. The pore diffusion factor of conventional porous materials was found to be much smaller than 1, indicating that there is a lot of room for improving the diffusion ability of the conventional catalysts and adsorbents, and could be significantly increased through adding small number of fibers into the conventional porous materials as template.展开更多
A novel photo-induced initiating system, 2,2-dimethoxy-2-phenylacetophenone (DMPA)/ferric tri(NN-diethyldithiocarbamate) [Fe(DC)(3)], was developed and used for the atom transfer radical polymerization (ATRP) of styre...A novel photo-induced initiating system, 2,2-dimethoxy-2-phenylacetophenone (DMPA)/ferric tri(NN-diethyldithiocarbamate) [Fe(DC)(3)], was developed and used for the atom transfer radical polymerization (ATRP) of styrene in toluene. The polymerization proceeds with DMPA as photo-initiator, Fe(DC)(3) as catalyst and DC as a reversible transfer group, while the halogen and ligands are free. Well-defined PSt was prepared and the polymerization mechanism revealed by end group analysis belongs to a reverse ATRP. Block copolymer was prepared by using thus obtained PSt as macroinitiator and Fe(DC)(2) as catalyst under UV light irradiation via a conventional ATRP process.展开更多
Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential dep...Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential deposition of hydrogen,or mild hydrogen evolution/OH adsorption)and have served as model electrodes for unraveling the structure-performance relation in electrocatalysis.With the advancement of in situ electrochemical microscopy/spectroscopy techniques,subtle surface restructuring under mild electrochemical conditions has been achieved in the last decade.Surface restructuring can considerably modify electrocatalytic properties by generating/destroying highly active sites,thereby interfering with the deduction of the structure-performance relation.In this review,we summarize recent progress in the restructuring of well-defined Pt(-based)electrode surfaces under mild electrochemical conditions.The importance of the meticulous structural characterization of Pt electrodes before,during,and after electrochemical measurements is demonstrated using CO adsorption/oxidation,hydrogen adsorption/evolution,and oxygen reduction as examples.The implications of present findings for correctly identifying the reaction mechanisms and kinetics of other electrocatalytic systems are also briefly discussed.展开更多
To avoid the damage to catalytic system in ATRP by the carboxyl groups in vinyl benzoic acid, a well defined poly( p vinyl benzoic acid) was synthesized via ATRP in the tertiary butyl ester form. The ATRP of t butyl p...To avoid the damage to catalytic system in ATRP by the carboxyl groups in vinyl benzoic acid, a well defined poly( p vinyl benzoic acid) was synthesized via ATRP in the tertiary butyl ester form. The ATRP of t butyl p vinyl benzoate ( t BVB) was studied kinetically. The results showed that t BVB can be polymerized in a controlled way by ATRP. It was found that the polymerization rate of t BVB is much faster than that of St, meaning that the electron withdrawing ester group affects the polymerization obviously. Well defined diblock copolymers of St and t BVB were prepared by using bromo terminated PBVBs as macroinitiators via ATRP. After removal of the t butyl group by hydrolysis, well defined amphiphilic diblock copolymers of styrene and p vinyl benzoic acid (PSt b PBVA) were obtained.展开更多
A new monomer-iniferter,allyl 2- N,N- diethyldithiocarbamylacetate (ADCA),was synthesized from allyl alcohol with chloroacetyl chloride then the chlorine groups were subsequently reacted with sodium diethyldithiocarba...A new monomer-iniferter,allyl 2- N,N- diethyldithiocarbamylacetate (ADCA),was synthesized from allyl alcohol with chloroacetyl chloride then the chlorine groups were subsequently reacted with sodium diethyldithiocarbamate. The ADCA was used for preparation of well\|defined functionalized polystyrene via radical polymerization of styrene (St) in bulk under UV light irradiation at ambient temperature. The bulk polymerization of St with ADCA proceeded a “living" process, i.e., both the yield and molecular weight of the resultant PSt increased with the increasing of reaction time, and the average number of end group Et 2NCSS is about 1. The well\|defined polymer was characterized by 1 H\|NMR and FT IR spectroscopies to be an α-allyloxycarbonylmethylene-ω-diethyldithiocarbamyl-polystyrene.Under UV light irradiation,the C-S bond of -ω-end groups of PSt can cleavage reversibly to initiate MMA polymerization forming a well\|defined PSt-b-PMMA copolymer.展开更多
基金supported by the Jiangsu Natural Science Foundation of China(BK20230329)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(22KJB150026)+1 种基金the Foundation of the National Natural Science Foundation of China(21802070 and 2217816)the National Key R&D Program of China(2018YFE0122600)。
文摘Ligand engineering for well-defined gold nanoclusters(Au NCs) is getting more extensive attention. Organizing the Au-ligand interfaces on gold NCs can achieve the structural and functional control. This review focuses on the Au-ligand interfaces including gold-phosphorus(Au-P), gold-sulfur(Au-S), gold-selenium(Au-Se), gold-carbon(Au-C), and gold-nitrogen(Au-N), derived from the bonding between Au atoms and the different ligands(e.g., organic phosphine, thiolate, selenolate, alkynyl,n-heterocyclic carbene and nitrogenous ligands). The formation mechanism of Au-ligand interfaces is well discussed. In addition, the effects of Au-ligand interfaces on the stability, optical property, and catalysis are also presented. We hope the advances in this research area can boost the development of Au NC sciences.
基金financial support from the Foundation of the Jiangsu Higher Education Institutions of China(22KJB150026)the National Natural Science Foundation of China(22178161,22101128).
文摘Atomically precise water-soluble gold nanoclusters(Au NCs)protected by organic ligands have attracted growing attention in serving as unique nanomaterials with the potential to generate theranostic tools(bioimaging,biosensing,and biotherapy),due to their ultrasmall size,superior photoluminescence,good biocompatibility,and nontoxicity.More importantly,Au NCs afford a well-defined atomic packing structure and molecular purity,providing a superior platform to unravel the structure−performance correlations for biodistribution,biological pharmacokinetics,and excretion of Au NCs.In this Review,we mainly survey the synthesis of water-soluble Au NCs and the recent progress in biomedicine of Au NCs,including bioimaging,biosensing,and biotherapy.The effects of ligand and size on the biomedical properties are discussed in detail.We hope that the advances in this research area can expand the applications of Au NCs in biomedicine.
基金supported by the National Nature Science Foundation of China (Grant No:91534120)。
文摘Internal diffusion of molecules in porous materials plays an important role in many chemical processes.However, the pore diffusion capacity of porous materials cannot be measured by conventional catalyst characterization methods. In the present paper, a pore diffusion factor, the ratio of the diffusionconstriction factor to the pore tortuosity of the porous materials, was proposed to measure the diffusion ability of pores inside solid materials, and a method was proposed for measuring the diffusion factor using a well-defined and uniform pore size material as a reference. The diffusion factor was calculated based on the effective diffusion coefficients and the diffusion-constriction factor and pore tortuosity of the reference porous materials. The pore diffusion factor measurement can be performed at room temperature and atmospheric pressure. The pore diffusion factor of conventional porous materials was found to be much smaller than 1, indicating that there is a lot of room for improving the diffusion ability of the conventional catalysts and adsorbents, and could be significantly increased through adding small number of fibers into the conventional porous materials as template.
文摘A novel photo-induced initiating system, 2,2-dimethoxy-2-phenylacetophenone (DMPA)/ferric tri(NN-diethyldithiocarbamate) [Fe(DC)(3)], was developed and used for the atom transfer radical polymerization (ATRP) of styrene in toluene. The polymerization proceeds with DMPA as photo-initiator, Fe(DC)(3) as catalyst and DC as a reversible transfer group, while the halogen and ligands are free. Well-defined PSt was prepared and the polymerization mechanism revealed by end group analysis belongs to a reverse ATRP. Block copolymer was prepared by using thus obtained PSt as macroinitiator and Fe(DC)(2) as catalyst under UV light irradiation via a conventional ATRP process.
文摘Since the 1980s,single-crystal Pt electrodes with well-defined surface structures have been deemed stable under mild electrochemical conditions(e.g.,in the potential region of electric double layers,underpotential deposition of hydrogen,or mild hydrogen evolution/OH adsorption)and have served as model electrodes for unraveling the structure-performance relation in electrocatalysis.With the advancement of in situ electrochemical microscopy/spectroscopy techniques,subtle surface restructuring under mild electrochemical conditions has been achieved in the last decade.Surface restructuring can considerably modify electrocatalytic properties by generating/destroying highly active sites,thereby interfering with the deduction of the structure-performance relation.In this review,we summarize recent progress in the restructuring of well-defined Pt(-based)electrode surfaces under mild electrochemical conditions.The importance of the meticulous structural characterization of Pt electrodes before,during,and after electrochemical measurements is demonstrated using CO adsorption/oxidation,hydrogen adsorption/evolution,and oxygen reduction as examples.The implications of present findings for correctly identifying the reaction mechanisms and kinetics of other electrocatalytic systems are also briefly discussed.
文摘To avoid the damage to catalytic system in ATRP by the carboxyl groups in vinyl benzoic acid, a well defined poly( p vinyl benzoic acid) was synthesized via ATRP in the tertiary butyl ester form. The ATRP of t butyl p vinyl benzoate ( t BVB) was studied kinetically. The results showed that t BVB can be polymerized in a controlled way by ATRP. It was found that the polymerization rate of t BVB is much faster than that of St, meaning that the electron withdrawing ester group affects the polymerization obviously. Well defined diblock copolymers of St and t BVB were prepared by using bromo terminated PBVBs as macroinitiators via ATRP. After removal of the t butyl group by hydrolysis, well defined amphiphilic diblock copolymers of styrene and p vinyl benzoic acid (PSt b PBVA) were obtained.
文摘A new monomer-iniferter,allyl 2- N,N- diethyldithiocarbamylacetate (ADCA),was synthesized from allyl alcohol with chloroacetyl chloride then the chlorine groups were subsequently reacted with sodium diethyldithiocarbamate. The ADCA was used for preparation of well\|defined functionalized polystyrene via radical polymerization of styrene (St) in bulk under UV light irradiation at ambient temperature. The bulk polymerization of St with ADCA proceeded a “living" process, i.e., both the yield and molecular weight of the resultant PSt increased with the increasing of reaction time, and the average number of end group Et 2NCSS is about 1. The well\|defined polymer was characterized by 1 H\|NMR and FT IR spectroscopies to be an α-allyloxycarbonylmethylene-ω-diethyldithiocarbamyl-polystyrene.Under UV light irradiation,the C-S bond of -ω-end groups of PSt can cleavage reversibly to initiate MMA polymerization forming a well\|defined PSt-b-PMMA copolymer.
