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The design of photocatalytic supramolecular systems composing of semiconductors and molecular metal complexes for CO2 reduction has attracted increasing attention. The supramolecular system combines the structural merits of semiconductors and metal complexes, where the semiconductor harvests light and undertakes the oxidative site, while the metal complex provides activity for CO2 reduction. The intermolecular charge transfer plays crucial role in ensuring photocatalytic performance. Here, we review the progress of photocatalytic supramolecular systems in reduction of CO2 and highlight the interfacial charge transfer pathways, as well as their state‐of‐the‐art characterization methods. The remaining challenges and prospects for further design of supramolecular photocatalysts are also presented. [ABSTRACT FROM AUTHOR]

Language is the most significant medium of human communication and one of the most crucial marks of a nation’s identity. Language differences are becoming a major source of worry and importance in contemporary multi-ethnic states. Language policies are developed and put into practice in these nations in a way that not only considers the historical, political, economic, and cultural aspects of the nation, but also protects the relationships and interests of the many nationalities. This study is divided into the following major sections. The introduction, which is the first section, includes a discussion of the topic’s goals and rationale, a review of the literature, the methodology and organizational framework of the paper, and an explanation of the paper’s important topics. The second section provides the policy’s overall backdrop, including the political and economic climate, the state of the language, the educational system, and the industry where it is formed. Language education policy development has the following characteristics: it is heavily impacted by political economics, and language education policy at the national and state level reflects both generalities and particularities. Language teaching and learning activities include early language education for children, a focus on communication activities and teacher training, and a close integration of school and home education. There is debate over whether teaching children’s multiple languages as part of their compulsory education causes stress for them. The implications of language education programs in other regions for China are examined in the final commentary.

This paper is a case study of the personal practical knowledge of two private middle school teachers, discussing the core teaching concepts and practices of private middle school teachers and their causes. The research shows that these two teachers have their own core concepts to guide teaching practice, and found that their personal experiences The social environment in which they live affects the formation of their core ideas to varying degrees. The article focuses on the great impact of the teaching and management mode of private schools on Teachers’ education ideas, and hopes to have more research in this regard. For a long time, private schools have been subordinates to the public education system, so the academic community has not paid enough attention to private teachers for a long time, but the impact of private school teachers on students is not weaker than that of public teachers, It should receive more attention from the academic community

Supramolecular systems consisting of covalent organic frameworks (COFs) and Ni complex are designed for robust photocatalytic reduction of CO2. Multiple heteroatom‐hydrogen bonding between the COF and Ni complex is identified to play a decisive role in the photoexcited electron transfer across the liquid‐solid interface. The diminution of steric groups on COF or metal complex can optimize catalytic performance, which is more attributable to the enhanced hydrogen‐bond interaction rather than their intrinsic activity. The photosystem with relatively strong strength of hydrogen bonds exhibits remarkable photocatalytic CO2‐to‐CO conversion, far superior to photosystems with supported atomic Ni or metal complex alone in the absence of hydrogen‐bond effect. Such heteroatom‐hydrogen bonds bridging electron transport pathway confers supramolecular system with high photocatalytic performance, providing an avenue to rationally design efficient and steadily available photosystems. [ABSTRACT FROM AUTHOR]

Supramolecular systems consisting of covalent organic frameworks (COFs) and Ni complex are designed for robust photocatalytic reduction of CO2. Multiple heteroatom‐hydrogen bonding between the COF and Ni complex is identified to play a decisive role in the photoexcited electron transfer across the liquid‐solid interface. The diminution of steric groups on COF or metal complex can optimize catalytic performance, which is more attributable to the enhanced hydrogen‐bond interaction rather than their intrinsic activity. The photosystem with relatively strong strength of hydrogen bonds exhibits remarkable photocatalytic CO2‐to‐CO conversion, far superior to photosystems with supported atomic Ni or metal complex alone in the absence of hydrogen‐bond effect. Such heteroatom‐hydrogen bonds bridging electron transport pathway confers supramolecular system with high photocatalytic performance, providing an avenue to rationally design efficient and steadily available photosystems. [ABSTRACT FROM AUTHOR]

Abstract: Covalent organic frameworks (COFs) are emerging as a class of photocatalyst for solar energy utilization. The separation of photogenerated excitons in COFs is crucial for their photocatalytic performance. Herein, we report a strategy to tune the electronic structure of COFs by implanting Zn ions within the framework to facilitate the separation and utilization of the photoinduced charges. Zn ions are incorporated within the shell of hollow COF cages (Zn@H‐TpPa) by a sacrificial template method with a formation of hollow cages. The implantation of Zn ions within the framework results in a redistribution of electron density and an increment of the polarity of the COF, as evidenced by experimental and computational analyses, and thus contributes to the separation and transport of charge carries. The Zn@H‐TpPa shows enhanced photocatalytic H2 production efficiency as compared to TpPa. The results demonstrate a new way to optimize the electronic structure of COFs for photocatalysis. [ABSTRACT FROM AUTHOR]

Crystalline covalent organic frameworks (COFs) are porous polymeric semiconductors with network topologies, which are built from the integration of selected organic blocks with covalent bond linkages. They have shown great promise for artificial photosynthesis, owing to broad light harvesting, high crystallinity, and high carrier mobility. This Minireview introduces state‐of‐the‐art COF photocatalysts based on different linkages and discusses the origin of photocatalytic activities for hydrogen evolution. Three typical COF photocatalysts, with linkages including imine (−C=N−), β‐ketoenamine (O=C−C=C−NH−), and vinylene (−C=C−), are discussed with a particular focus on the advancements in synthetic methodologies and structural design, as well as photoelectronic properties that are relevant to photocatalytic performance. The Minireview is expected to elucidate their structure–property relationships and the way to design photoactive COFs with enhanced performances. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have been regarded as promising photocatalytic materials. However, the sluggish diffusion of photoinduced charges in a single‐component COF remains the obstacles that have to be overcome. Here, we demonstrate a synthesis of a COF bearing dual cocatalysts Co3O4 and Re complex as photocatalyst for water oxidation. The dual cocatalysts are coordinated on the COF, and enable the spatial separation of photoinduced charges. The generated electrons were attracted to Re moiety, while the holes were localized on Co3O4 cocatalyst for water oxidation to produce O2 product. The synergy of dual cocatalysts of COF promote the charge separation and redox reaction. Moreover, hydroxyl radicals generated from the hydration of COF contribute to O−O bond formation, which is the key step of O2 formation. Accordingly, an excellent O2 production rate of 400 μmol g−1 h−1 under visible light irradiation was obtained. This work may pave the way to the development of highly efficient COF photocatalysts for solar energy conversion. [ABSTRACT FROM AUTHOR]

Supramolecular systems consisting of covalent organic frameworks (COFs) and Ni complex are designed for robust photocatalytic reduction of CO2. Multiple heteroatom‐hydrogen bonding between the COF and Ni complex is identified to play a decisive role in the photoexcited electron transfer across the liquid‐solid interface. The diminution of steric groups on COF or metal complex can optimize catalytic performance, which is more attributable to the enhanced hydrogen‐bond interaction rather than their intrinsic activity. The photosystem with relatively strong strength of hydrogen bonds exhibits remarkable photocatalytic CO2‐to‐CO conversion, far superior to photosystems with supported atomic Ni or metal complex alone in the absence of hydrogen‐bond effect. Such heteroatom‐hydrogen bonds bridging electron transport pathway confers supramolecular system with high photocatalytic performance, providing an avenue to rationally design efficient and steadily available photosystems. [ABSTRACT FROM AUTHOR]

Supramolecular systems consisting of covalent organic frameworks (COFs) and Ni complex are designed for robust photocatalytic reduction of CO2. Multiple heteroatom‐hydrogen bonding between the COF and Ni complex is identified to play a decisive role in the photoexcited electron transfer across the liquid‐solid interface. The diminution of steric groups on COF or metal complex can optimize catalytic performance, which is more attributable to the enhanced hydrogen‐bond interaction rather than their intrinsic activity. The photosystem with relatively strong strength of hydrogen bonds exhibits remarkable photocatalytic CO2‐to‐CO conversion, far superior to photosystems with supported atomic Ni or metal complex alone in the absence of hydrogen‐bond effect. Such heteroatom‐hydrogen bonds bridging electron transport pathway confers supramolecular system with high photocatalytic performance, providing an avenue to rationally design efficient and steadily available photosystems. [ABSTRACT FROM AUTHOR]

We demonstrate an electrostatic confinement-induced charge transfer pathway in a supramolecular photocatalyst comprising of an ionic covalent organic framework (COF) and cationic metal complexes. The dynamic electrostatic interactions not only attract cations around the COF to accept photogenerated electrons, but also allows for a retention of homogeneous catalytic characters of complexes, making a subtle balance. Accordingly, the electrostatic confinement effect facilitates the forward electron transfer from a photoexcited COF to cationic Co complex, realizing a remarkable photocatalytic CO2 reduction performance. Its catalytic efficiency is far superior to the supramolecular counterparts with Van-der-Waals or hydrogen bonding interactions. This work presents an insight for enhancing charge transfer in supramolecular systems, and provides an effective approach for construction of highly efficient photocatalysts., (© 2024 Wiley‐VCH GmbH.)

Metal complex-based photocatalysts are promising for CO2 reduction. Their catalytic performances greatly rely on the synergy of ligands and metal ions. Here, we demonstrate an assembly of covalent organic cage (COC) and metal ions for photocatalytic CO2 reduction. The coordinated metal serves as catalytically active site for CO2 reduction, while the cage not only chelates the metal site, but also enhances the local concentration of CO2 around metal site, and decreases the key intermediate reaction energy barrier, thereby promoting the CO2 reduction reaction kinetically and thermodynamically. Accordingly, a Ni metalized COC exhibited outstanding photocatalytic performance in CO2-to-CO conversion under visible light irradiation. This study highlights the feasibility and advantage of organic cages for the construction of photocatalysts for artificial photosynthesis., (© 2024 Wiley‐VCH GmbH.)

The design of photocatalytic supramolecular systems composing of semiconductors and molecular metal complexes for CO 2 reduction has attracted increasing attention. The supramolecular system combines the structural merits of semiconductors and metal complexes, where the semiconductor harvests light and undertakes the oxidative site, while the metal complex provides activity for CO 2 reduction. The intermolecular charge transfer plays crucial role in ensuring photocatalytic performance. Here, we review the progress of photocatalytic supramolecular systems in reduction of CO 2 and highlight the interfacial charge transfer pathways, as well as their state-of-the-art characterization methods. The remaining challenges and prospects for further design of supramolecular photocatalysts are also presented., (© 2024 Wiley-VCH GmbH.)

Crystalline covalent organic frameworks (COFs) are porous polymeric semiconductors with network topologies, which are built from the integration of selected organic blocks with covalent bond linkages. They have shown great promise for artificial photosynthesis, owing to broad light harvesting, high crystallinity, and high carrier mobility. This Minireview introduces state-of-the-art COF photocatalysts based on different linkages and discusses the origin of photocatalytic activities for hydrogen evolution. Three typical COF photocatalysts, with linkages including imine (-C=N-), β-ketoenamine (O=C-C=C-NH-), and vinylene (-C=C-), are discussed with a particular focus on the advancements in synthetic methodologies and structural design, as well as photoelectronic properties that are relevant to photocatalytic performance. The Minireview is expected to elucidate their structure-property relationships and the way to design photoactive COFs with enhanced performances., (© 2021 Wiley-VCH GmbH.)