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The transformative development of international Chinese language education has entered a new period, showing emerging development trends such as diversification, marketization, and digitalization. This study creates a unified classification system that links Chinese and English knowledge and complements each other based on the cross-language knowledge mapping of Chinese cultural knowledge. Additionally, a knowledge base for sharing cultural knowledge between Chinese and English is being constructed to provide strong support for information retrieval and machine translation. The data information is stored in plain text format for ontology and knowledge to make it easier to use and process teaching resources. The results show that in the teaching feedback, the average scores are all over 3, indicating that the teaching effect of the resource is positive overall, and the standard deviation values range from 0.1560 to 0.9812, indicating significant differences between different individuals. The above findings can be a valuable resource for constructing and implementing international Chinese language education network resources.

The [AuxAg16‐x(SAdm)8(Dppe)2] nanocluster with aggregation‐induced emission (AIE) was synthesized from a non‐fluorescent [Au9Ag12(SAdm)4(Dppm)6Cl6](SbF6)3 nanocluster via a ligand‐exchange engineering (Dppe=1,2‐Bis(diphenylphosphino)ethane, Dppm=Bis(diphenylphosphino)methane, HSAdm=1‐Adamantanethiol). The nanocluster has a Au‐doped icosahedral AuxAg13‐x core, capped by two Ag(SR)3, one Ag(SR)2 and two Dppe ligands. By changing the achiral Dppe ligand into a chiral dbpb ligand ((2S,3S)‐(‐)‐Bis(diphenylphosphino)butane or (2R,3R)‐(+)‐2,3‐Bis(diphenylphosphino)butane), chiral nanoclusters are obtained. ESI‐MS and UV‐vis spectroscopy were performed to track the reaction. This work provides guidance for the construction of new clusters by etching clusters with multidentate phosphine ligands. [ABSTRACT FROM AUTHOR]

An intermediate-sized atomically precise metalloid silver nanocluster [Ag71(SR)31(Dppm)](SbF6)2 (Dppm = bis (diphenylphosphino)methane, SR = S-tBu) is reported, which comprises one building block Ag64, six SR5 pentagons, one sole SR ligand, a DppmAg2 handle, and an Ag5 lid. Structurally, a decahedron Ag23 kernel is observed in the metalloid silver nanocluster. Moreover, the Ag64 unit provides insights into the growth of large clusters such as Ag136(SR)64Cl3 and Ag141(SR)40Br12via assembly. The observed decahedron Ag23 provides a deeper understanding on Marks decahedron in larger nanoclusters, and the [Ag71(S-tBu)31(Dppm)](SbF6)2 uses Ag64 as a building block to predict the structure of larger metalloid nanoclusters. [ABSTRACT FROM AUTHOR]

An intermediate-sized atomically precise metalloid silver nanocluster [Ag71(SR)31(Dppm)](SbF6)2 (Dppm = bis (diphenylphosphino)methane, SR = S-tBu) is reported, which comprises one building block Ag64, six SR5 pentagons, one sole SR ligand, a DppmAg2 handle, and an Ag5 lid. Structurally, a decahedron Ag23 kernel is observed in the metalloid silver nanocluster. Moreover, the Ag64 unit provides insights into the growth of large clusters such as Ag136(SR)64Cl3 and Ag141(SR)40Br12via assembly. The observed decahedron Ag23 provides a deeper understanding on Marks decahedron in larger nanoclusters, and the [Ag71(S-tBu)31(Dppm)](SbF6)2 uses Ag64 as a building block to predict the structure of larger metalloid nanoclusters. [ABSTRACT FROM AUTHOR]

Ultrasmall nanoclusters are emerging nanocatalysts due to their distinct physico‐chemical properties. However, the instability and agglomeration of these nanoclusters restrict their practical application. Herein, we designed a negatively charged cross‐linked polystyrene (PS) microsphere as support and decorated it with positively charged ultrasmall [Au4Cu5(Dppm)2(C6H11S)6]+[BPh4]− (Au4Cu5, in which Dppm stands for bis‐(diphenylphosphino)methane) nanoclusters through strong electrostatic adsorption, as evidenced by X‐ray photoelectron spectroscopy. The PS@Au4Cu5 nanocomposites were well‐dispersed in water, exhibiting enhanced catalytic activity for the reduction reaction of 4‐nitrophenol to produce 4‐aminophenol. These findings open promising opportunities for supported nanocluster catalysis. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis and total structure of a Cu-rich alloy nanocluster protected by twelve adamantanethiolate ligands, i.e., [Ag13Cu10(SAdm)12]X3 (–SAdm = SC10H15, X = counterion), which was confirmed by single-crystal X-ray structure determination and electrospray ionization mass spectrometry (ESI-MS). X-ray crystallographic analysis indicated that [Ag13Cu10(SAdm)12]X3 consisted of an icosahedral Ag13 core, covered by a cage-like shell of Cu10(SAdm)12. Furthermore, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations on the geometric and electronic structures and KS orbitals and UV-vis spectroscopy were performed on the model [Ag13Cu10(SMe)12]3+ and its monometallic analog [Ag23(SMe)12]3+. This work will deepen the understanding of core–shell Ag–Cu alloy nanoclusters. [ABSTRACT FROM AUTHOR]

The high‐dimensional (that is, three‐dimensional (3D)) assembly of nanomaterials is an effective means of improving their properties; however, achieving this assembly at the atomic level remains challenging. Herein, we obtained a novel nanocluster, [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl (Dppp=1,3‐bis(diphenylphosphino)propane) showing a 3D octameric assembly mode involving the kernel penetration of eight complete icosahedral Au@Ag10Au2 units for the first time. The atomically precise structure was determined by single‐crystal X‐ray diffraction, and further confirmed by thermogravimetric analysis, X‐ray photoelectron spectroscopy, and electrospray ionization mass spectrometry measurements. Furthermore, ligand‐induced transformation prompted the conversion of [Au8Ag57(Dppp)4(C6H11S)32Cl2]Cl, with complete octameric fusion into [Au8Ag55(Dppp)4(C6H11S)34][BPh4]2, with incomplete octameric fusion. These observations will hopefully facilitate further research on the assembly of M13 nanobuilding blocks. [ABSTRACT FROM AUTHOR]

Herein, we report the first silver-rich nanocluster containing an open icosahedral Au1Ag12 core. This nanocluster is determined to be [Au1Ag24(Dppm)3(SR)17]2+ (where Dppm is short for bis-(diphenylphosphino)methane and SR is short for cyclohexyl mercaptan) by single-crystal X-ray diffraction and electrospray ionization mass spectrometry (ESI-MS). The Au1Ag24 consists of an open icosahedral Au1Ag12, which contains six free valence electrons surrounded by a big ring motif Ag12(Dppm)3(SR)15 and two SR groups. Density Functional Theory (DFT) provided insight into the relationship between the structure and its performance. [ABSTRACT FROM AUTHOR]

The exploration of specific heavy doping of silver atoms into icosahedral Au 13 clusters and their electronic structures and properties has been somewhat limited. Herein, we report two heavily Ag doped nanoclusters, [Au 7 Ag 6 (C 7 H 4 NOS) 4 (Dppf) 3 Cl] 0 and [Au 7 Ag 6 (C 7 H 4 NOS) 3 (Dppf) 3 Cl](SbF 6 ) (Au 7 Ag 6 -0 and Au 7 Ag 6 -1, respectively) [C 7 H 4 NOSH = 2-mercaptobenzoxazole, and Dppf = 1,1'-bis(diphenylphosphino)ferrocene]. The electronic structures and superatomic orbitals of nanoclusters were determined by density functional theory (DFT) calculations, and the energy degeneracy of the superatomic orbitals of Au 7 Ag 6 -1 is higher than that of Au 7 Ag 6 -0. Transient absorption spectroscopy was performed, revealing that Au 7 Ag 6 -0 significantly extends the excited-state lifetime. Both nanoclusters were supported on activated carbon for the oxygen reduction reaction. DFT calculations confirm that the catalytic activities mainly stem from the carbon atom of ferrocene rather than the iron atom. This study not only sheds light on the preparation of icosahedral alloy clusters but also provides insights into the regulation of icosahedral superatomic structure and electrocatalytic properties.

Precise atomically assembled nanoclusters provide a great platform to elucidate the evolution of the assembly of building blocks. Herein, a large icosahedral (M 13 )-based silver-gold alloy nanocluster [Au 12 Ag 60 (S- c -C 6 H 11 ) 31 Br 9 (Dppp) 6 ]Br 2 (dppp = 1,3-bis(diphenylphosphino)propane) is reported. Structurally, Au 12 Ag 60 consists of an Au 12 Ag 40 kernel, which is viewed as the interpenetration of ten twisted complete icosahedrons (M 13 ) and two missing icosahedrons (M 12 ), and this is surrounded by a complex metal-organic shell. Benefiting from the extra doping of eight to twelve Au atoms, the octameric assembly was increased to a twelve-mer assembly. The time-dependent density functional theory (TDDFT) method with a Tamm-Dancoff approximation (TDA) was performed to investigate the difference in the optical properties of Au 12 Ag 60 and Au 8 Ag 57 . The results indicate that the difference in the amount of Au atoms results in different optical properties. Furthermore, transient absorption spectroscopy (TA) was also performed, revealing that a twelve-mer assembly greatly enhances the excited-state lifetime. The [Au 12 Ag 60 (S- c -C 6 H 11 ) 31 Br 9 (Dppp) 6 ]Br 2 alloy nanocluster has provided a breakthrough in the number of icosahedral M 13 assemblies, i.e. , achieving a twelve-mer assembly, helping to elucidate the fusion growth of M 13 -based assembled nanoclusters as well as their geometric/electronic structure correlations, which will promote further research on the assembly of M 13 nano-building blocks, especially on their optical properties.

The [Au x Ag 16-x (SAdm) 8 (Dppe) 2 ] nanocluster with aggregation-induced emission (AIE) was synthesized from a non-fluorescent [Au 9 Ag 12 (SAdm) 4 (Dppm) 6 Cl 6 ](SbF 6 ) 3 nanocluster via a ligand-exchange engineering (Dppe=1,2-Bis(diphenylphosphino)ethane, Dppm=Bis(diphenylphosphino)methane, HSAdm=1-Adamantanethiol). The nanocluster has a Au-doped icosahedral Au x Ag 13-x core, capped by two Ag(SR) 3 , one Ag(SR) 2 and two Dppe ligands. By changing the achiral Dppe ligand into a chiral dbpb ligand ((2S,3S)-(-)-Bis(diphenylphosphino)butane or (2R,3R)-(+)-2,3-Bis(diphenylphosphino)butane), chiral nanoclusters are obtained. ESI-MS and UV-vis spectroscopy were performed to track the reaction. This work provides guidance for the construction of new clusters by etching clusters with multidentate phosphine ligands., (© 2021 Wiley-VCH GmbH.)

An intermediate-sized atomically precise metalloid silver nanocluster [Ag 71 (SR) 31 (Dppm)](SbF 6 ) 2 (Dppm = bis (diphenylphosphino)methane, SR = S- t Bu) is reported, which comprises one building block Ag 64 , six SR 5 pentagons, one sole SR ligand, a DppmAg 2 handle, and an Ag 5 lid. Structurally, a decahedron Ag 23 kernel is observed in the metalloid silver nanocluster. Moreover, the Ag 64 unit provides insights into the growth of large clusters such as Ag 136 (SR) 64 Cl 3 and Ag 141 (SR) 40 Br 12 via assembly. The observed decahedron Ag 23 provides a deeper understanding on Marks decahedron in larger nanoclusters, and the [Ag 71 (S- t Bu) 31 (Dppm)](SbF 6 ) 2 uses Ag 64 as a building block to predict the structure of larger metalloid nanoclusters.

Herein, we report the synthesis and total structure of a Cu-rich alloy nanocluster protected by twelve adamantanethiolate ligands, i.e., [Ag 13 Cu 10 (SAdm) 12 ]X 3 (-SAdm = SC 10 H 15 , X = counterion), which was confirmed by single-crystal X-ray structure determination and electrospray ionization mass spectrometry (ESI-MS). X-ray crystallographic analysis indicated that [Ag 13 Cu 10 (SAdm) 12 ]X 3 consisted of an icosahedral Ag 13 core, covered by a cage-like shell of Cu 10 (SAdm) 12 . Furthermore, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations on the geometric and electronic structures and KS orbitals and UV-vis spectroscopy were performed on the model [Ag 13 Cu 10 (SMe) 12 ] 3+ and its monometallic analog [Ag 23 (SMe) 12 ] 3+ . This work will deepen the understanding of core-shell Ag-Cu alloy nanoclusters.

Atomically precise engineering on the nanocluster surface remains highly desirable for the fundamental understanding of how surface structures of a nanocluster contribute to its overall properties. In this paper, the concept of "graft-onto" has been exploited to facilitate nanocluster growth on surface structures. Specifically, the Ag 2 (DPPM)Cl 2 complex is used for re-constructing the surface structure of Pt 1 Ag 28 (SR) 18 (PPh 3 ) 4 ( Pt 1 Ag 28 , SR = 1-adamantanethiolate) and producing a size-growth nanocluster - Pt 1 Ag 31 (SR) 16 (DPPM) 3 Cl 3 ( Pt 1 Ag 31 ). The grafting effect of Ag 2 (DPPM)Cl 2 induces both direct changes on the surface structure ( e.g. , size growth, structural transformation, and surface rotation) and indirect changes on the kernel structure (from a fcc configuration to an icosahedral configuration). Remarkable differences have been observed by comparing optical properties between Pt 1 Ag 28 and Pt 1 Ag 31 . Significantly, Pt 1 Ag 31 exhibits high photo-luminescent intensity with a quantum yield of 29.3%, which is six times that of the Pt 1 Ag 28 . Overall, this work presents a new approach ( i.e. , graft-onto) for the precise dictation of nanocluster surface structures at the atomic level., (This journal is © The Royal Society of Chemistry 2020.)

Herein, we report the first silver-rich nanocluster containing an open icosahedral Au1Ag12 core. This nanocluster is determined to be [Au1Ag24(Dppm)3(SR)17]2+ (where Dppm is short for bis-(diphenylphosphino)methane and SR is short for cyclohexyl mercaptan) by single-crystal X-ray diffraction and electrospray ionization mass spectrometry (ESI-MS). The Au1Ag24 consists of an open icosahedral Au1Ag12, which contains six free valence electrons surrounded by a big ring motif Ag12(Dppm)3(SR)15 and two SR groups. Density Functional Theory (DFT) provided insight into the relationship between the structure and its performance.