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Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 4908-4915页

作者： Xu Han Xueying Ge Wen-Wen He Wangwang Shen Tao Zhou Jian-Sen Wang Rong-Lin Zhong Abdullah mal-Enizi Ayman Nafady shengqian ma School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China Department of Chemistry University of North Texas1508 W.Mulberry St.DentonTX 76201USA Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen production.In this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active sites.The fabricated PtNPs@covalent triazine-based framework-1(CTF-1)composite accomplished a significantly high rate of hydrogen evolution(20.0 mmol·g^(−1)·h^(−1),apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine CTF-1.Theoretical calculations revealed that the strong electron transfer(Q(Pt)=−0.726 qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1,and qe is the unit of charge transfer quantity)between PtNPs and CTF-1 triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1,thereby enabling high stability and excellent hydrogen production efficiency.Importantly,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1 is much lower than that of the unmodified CTF-1,leading to a much lower intermediate state and hence a significant improvement in photocatalytic performance.The overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts.

关键词： Pt nanoparticles covalent triazine-based framework-1(CTF-1) photocatalysts hydrogen evolution reaction

Holocene Hydroclimatic Variations in the Asian Drylands:Current Understanding and Future Perspectives

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Journal of Earth Science 2024年第1期35卷 292-295页

作者： Guoqiang Ding shengqian Chen Yuanhao Sun Shuai ma Jianhui Chen MOE Key Laboratory of West China's Environmental System College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Alpine Paleoecology and Human Adaptation Group State Key Laboratory of Tibetan Plateau Earth SystemEnvironment and ResourcesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

0 INTRODUCTION.The intensification of global warming is generating increasing risks to human society and sustainable development,which are of growing concern to the international scientific community and policymakers(Sun,2023).The ecosystems of the Asian drylands are fragile and highly sensitive to global changes;moreover,while these drylands are the most important areas of oasis agriculture on Earth,their water resources are being adversely impacted by ongoing climate change(Zhang et al.,2023).Hence,an improved understanding of the patterns of climate change in this region is important and attracting increasing research attention.

关键词： Asian Holocene climatic

Striking 2D materials: exfoliation of molecular crystals

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Science China Chemistry 2022年第6期65卷 1005-1006页

作者： Yin Zhang shengqian ma Department of Chemistry University of North TexasDentonTX76201USA

Ultrathin nanosheets, which are often prepared from bulk crystals by exfoliating, represent an intriguing type of twodimensional (2D) materials with mechanical, electronic,optical, and thermal properties that are distinct from their pristine bulk crystals. They are promising in various applications, including (opto)electronics, chemical sensing, catalysis, and separation, because of their unique properties and high surface area. Previously, the operationally simple exfoliation method is only applicable to bulk crystals with weak interactions between the layers.

关键词： crystals separation catalysis

Substituent engineering in g-C_(3)N_(4)/COF heterojunctions for rapid charge separation and high photo-redox activity

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Science China Chemistry 2022年第9期65卷 1704-1709页

作者： Jiayun Guo Dongge ma Fulin Sun Guilin Zhuang Qi Wang Abdullah M.Al-Enizi Ayman Nafady shengqian ma School of Environmental Science and Engineering Zhejiang Gongshang UniversityHangzhou 310018China Department of Chemistry College of Chemistry and Materials EngineeringBeijing Technology and Business UniversityBeijing 100048China Institute of Industrial Catalysis College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310023China Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia Department of Chemistry University of North TexasDentonTX 76201USA

The heterojunction composed of covalent organic frameworks(COFs)with adjustable structure and other photocatalysts has great potential in the field of photocatalysis.However,effectively enhancing the photocatalytic performance of organic heterojunctions by designing the structure of COFs has not been explored.Herein,TPB-TP-COFs fabricated from 1,3,5-tris(4-amino-phenyl)benzene(TPB)and terephthalaldehyde(TP)with different substituents(−H,−OH,−OCH_(3),−Br and−F groups),were applied to construct g-C_(3)N_(4)/COFs.The performance improvement of the heterojunction could be affected by substituents,and only−OCH_(3) groups can significantly improve both the photocatalytic phenol oxidation and Cr(Ⅵ)reduction.DFT calculation demonstrated that the substituents will affect the electron cloud distribution of CBM,and the location of CBM in the TPB segment is beneficial for the charge transport between TPB-TP-OCH_(3) and g-C_(3)N_(4).The enhanced charge transfer from g-C_(3)N_(4) to TPB segment and the improved light absorption of TPB-TP-OCH_(3) jointly optimize the photocatalytic redox capacity of g-C_(3)N_(4)/TPB-TP-OCH_(3).On the basis of this study,regulating the electronic effects of semiconductors played a vital role in improving photocatalytic performance in organic heterojunctions.

关键词： monofluorophosphate g-C_(3)N_(4) heterojunction photocatalysis substituent electronegativity

Metallocorrole-based porous organic polymers as a heterogeneous catalytic nanoplatform for efficient carbon dioxide conversion

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Nano Research 2022年第2期15卷 1145-1152页

作者： Yanming Zhao Yunlei Peng Chuan Shan Zhou Lu Lukasz Wojtas Zhenjie Zhang Bao Zhang Yaqing Feng shengqian ma School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Department of Chemistry University of North TexasDentonTexas 76201USA College of Chemistry Nankai UniversityTianjin 300071China Department of Chemistry University of South FloridaTampaFlorida 33620USA Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072China

Metallocorrole macrocycles that represent a burgeoning class of attractive metal-complexes from the porphyrinoid family,have attracted great interest in recent years owing to their unique structure and excellent performance revealed in many fields,yet further functionalization through incorporating these motifs into porous nanomaterials employing the bottom-up approach is still scarce and remains synthetically challenging.Here,we report the targeted synthesis of porous organic polymers(POPs)constructed from custom-designed Mn and Fe-corrole complex building units,respectively denoted as CorPOP-1(Mn)and CorPOP-1(FeCl).Specifically,the robust CorPOP-1(Mn)bearing Mn-corrole active centers displays superior heterogeneous catalytic activity toward solvent-free cycloaddition of carbon dioxide(CO_(2))with epoxides to form cyclic carbonates under mild reaction conditions as compared with the homogeneous counterpart.CorPOP-1(Mn)can be easily recycled and does not show significant loss of reactivity after seven successive cycles.This work highlights the potential of metallocorrole-based porous solid catalysts for targeting CO_(2) transformations,and would provide a guide for the task-specific development of more corrole-based multifunctional materials for extended applications.

关键词： corrole porphyrinoid derivatives heterogenization porous organic polymers(POPs) CO_(2)conversion heterogeneous catalysis

Utilization of cationic microporous metal-organic framework for efficient Xe/Kr separation

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Nano Research 2022年第8期15卷 7559-7564页

作者： Lingshan Gong Ying Liu Junyu Ren Abdullah mal-Enizi Ayman Nafady Yingxiang Ye Zongbi Bao shengqian ma Department of Chemistry University of North TexasDentonTexas 76201USA Key Laboratory of Biomass Chemical Engineering of Ministry of Education College of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027China Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

The separation of xenon/krypton(Xe/Kr)mixtures plays a vital role in the industrial process of manufacturing high-purity xenon.Compared with energy-intensive cryogenic distillation,porous materials based on physical adsorption are very promising in the low-cost and energy-saving separation processes.Herein,we show that a cationic metal-organic framework(named as FJU-55)exhibits highly efficient Xe/Kr separation performance,which can be attributable to its uniform three-dimensional(3D)interconnection channels and the electro-positive features as the host framework.Moreover,FJU-55 demonstrates good Xe adsorption capacity of 1.41 mmol/g and excellent Xe/Kr selectivity of 10(298 K and 100 kPa),together with a high Qst value of 39.4 kJ/mol at low coverage area.The superior Xe/Kr separation performance of FJU-55 was further confirmed by the dynamic breakthrough experiments.Results obtained via molecular modeling studies have revealed that the suitable pore size and abundant accessible aromatic ligands in FJU-55 could offer strong multiple C–H∙∙∙Xe interactions,which play a collaborative role in this challenging gas separation task.

关键词： gas separation cationic metal-organic framework microporous xenon capture krypton

Emerging technologies for uranium extraction from seawater

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Science China Chemistry 2022年第12期65卷 2335-2337页

作者： Hui Yang Yanfang Liu Zhongshan Chen Geoffery I.N.Waterhouse shengqian ma Xiangke Wang College of Environmental Science and Engineering North China Electric Power UniversityBeijing102206China School of Chemical Sciences The University of AucklandAuckland1142New Zealand Department of Chemistry University of North TexasDentonTexas76201USA

The use of enriched uranium(^(235)U)in nuclear fission reactors allows electricity generation with negligible CO_(2) emissions.Thus,nuclear energy is expected to play an important role in global efforts to decarbonize the energy sector[1].To meet the energy needs of future societies and achieve zero-emissions targets,more nuclear reactors will be needed,which increases demand for uranium fuel.

关键词： negligible seawater

VOC emitted by biopharmaceutical industries:Source profiles,health risks,and secondary pollution

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Journal of Environmental Sciences 2024年第1期135卷 570-584页

作者： Jiawei ma Lin Li State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for VOCs Pollution Control material&Technology University of Chinese Academy of SciencesBeijing 101408China

The biopharmaceutical industry contributes substantially to volatile organic compounds(VOCs)emissions,causing growing concerns and social developmental conflicts.This study conducted an on-site investigation of the process-based emission of VOCs from three biopharmaceutical enterprises.In the workshops of the three enterprises,26 VOCs were detected,which could be sorted into 4 classes:hydrocarbons,aromatic hydrocarbons,oxygen-containing compounds,and nitrogen-containing compounds.Ketones were the main components of waste gases,accounting for 44.13%-77.85%of the overall VOCs.Process-based source profiles were compiled for each process unit,with the fermentation and extraction units of tiamulin fumarate being the main source of VOC emissions.Dimethyl heptanone,vinyl acetate,diethylamine,propylene glycol methyl ether(PGME),and benzene were screened as priority pollutants through a fuzzy comprehensive evaluation system.Ground level concentration simulation results of the Gauss plume diffusion model demonstrated that the diffusivity of VOCs in the atmosphere was relatively high,indicating potential non-carcinogenic and carcinogenic risks 1.5-2 km downwind.Furthermore,the process-based formation potentials of ozone and secondary organic aerosols(SOAs)were determined and indicated that N-methyl-2-pyrrolidone,dimethyl heptanone,and PGME should be preferentially controlled to reduce the ozone formation potential,whereas the control of benzene and chlorobenzene should be prioritized to reduce the generation of SOAs.Our results provide a basis for understanding the characteristics of VOC emission by biopharmaceutical industries and their diffusion,potentially allowing the development of measures to reduce health risks and secondary pollution.

关键词： Biopharmaceutical Volatile organic compound Priority pollutant Exposure risk Secondary pollution

Nuclear phylogenomics of angiosperms and insights into their relationships and evolution

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Journal of Integrative Plant Biology 2024年第3期66卷 546-578页

作者： Guojin Zhang Hong ma College of Life Sciences Hunan Normal UniversityChangsha 410081China Department of Biology 510 Mueller LaboratoryHuck Institutes of the Life SciencesThe Pennsylvania State UniversityUniversity ParkPA 16802USA

Angiosperms(flowering plants) are by far the most diverse land plant group with over 300,000 species. The sudden appearance of diverse angiosperms in the fossil record was referred to by Darwin as the “abominable mystery,”hence contributing to the heightened interest in angiosperm evolution. Angiosperms display wide ranges of morphological, physiological,and ecological characters, some of which have probably influenced their species richness. The evolutionary analyses of these characteristics help to address questions of angiosperm diversification and require well resolved phylogeny. Following the great successes of phylogenetic analyses using plastid sequences,dozens to thousands of nuclear genes from next-generation sequencing have been used in angiosperm phylogenomic analyses, providing well resolved phylogenies and new insights into the evolution of angiosperms. In this review we focus on recent nuclear phylogenomic analyses of large angiosperm clades, orders, families,and subdivisions of some families and provide a summarized Nuclear Phylogenetic Tree of Angiosperm Families. The newly established nuclear phylogenetic relationships are highlighted and compared with previous phylogenetic results. The sequenced genomes of Amborella,Nymphaea, Chloranthus, Ceratophyllum, and species of monocots, magnoliids, and basal eudicots, have facilitated the phylogenomics of relationships among five major angiosperms clades. All but one of the 64 angiosperm orders were included in nuclear phylogenomics with well resolved relationships except the placements of several orders. Most families have been included with robust and highly supported placements, especially for relationships within several large and important orders and families.Additionally, we examine the divergence time estimation and biogeographic analyses of angiosperm on the basis of the nuclear phylogenomic frameworks and discuss the differences compared with previous analyses. Furthermore,we discuss the implications of nuclear phylogenomic analyses on ancestral

关键词： angiosperms evolution flowering plants nuclear gene phylogenomics phylogeny