期刊文献+
共找到906篇文章
< 1 2 46 >
每页显示 20 50 100
Study on the covalence of Cu and chemical bonding in an inorganic fullerene-like molecule,[CuCl]_(20)[Cp^(*)FeP_(5)]_(12)[Cu-(CH_(3)CN)_(2)^(+)Cl^(-)]_(5),by a density functional approach
1
作者 WANG Bingwu XU Guangxian CHEN Zhida 《Science China Chemistry》 SCIE EI CAS 2004年第2期91-97,共7页
The electronic structure and chemical bonding in a recently synthesized inorganic fullerene-like molecule, [CuCl]20[Cp*FeP5]12[Cu-(CH3CN) + 2Cl?]5 has been studied by a density functional approach. Geometrical optimiz... The electronic structure and chemical bonding in a recently synthesized inorganic fullerene-like molecule, [CuCl]20[Cp*FeP5]12[Cu-(CH3CN) + 2Cl?]5 has been studied by a density functional approach. Geometrical optimization of the three basic structural units of the molecule is performed with Amsterdam Density Functional Program. The results are in agreement with the experiment. Localized MO’s obtained by Boys-Foster method give a clear picture of the chemical bonding in this molecule. The reason why CuCl can react with Cp*FeP5 in solvent CH3CN to form the fullerene-like molecule is explained in terms of the soft-hard Lewis acid base theory and a new concept of covalence. 展开更多
关键词 INORGANIC fullerene-like molecule chemical bonding covalence copper.
原文传递
The Covalences of Be and CI in Beryllium Chloride
2
作者 义祥辉 黎乐民 +1 位作者 单立安 徐光宪 《Chinese Science Bulletin》 SCIE EI CAS 1993年第4期299-302,共4页
1 Introduction Generally beryllium is considered as a bivalent element, which implies that its oxidation state is+2. However, almost all compounds of beryllium are covalent ones with partial ionic character, even thos... 1 Introduction Generally beryllium is considered as a bivalent element, which implies that its oxidation state is+2. However, almost all compounds of beryllium are covalent ones with partial ionic character, even those formed with the most electronegative elements F and O, e. g. BeF<sub>2</sub> and BeO. The coordination numbers of beryllium in its compounds are 2, 3 and 4. Some people consider the coordination number as covalence, but we think that they are 展开更多
关键词 covalence NBO BERYLLIUM chloride.
在线阅读 下载PDF
Dynamic Network‑and Microcellular Architecture‑Driven Biomass Elastomer toward Sustainable and Versatile Soft Electronics
3
作者 Shanqiu Liu Yi Shen +5 位作者 Yizhen Li Yunjie Mo Enze Yu Taotao Ge Ping Li Jingguo Li 《Nano-Micro Letters》 2026年第3期368-387,共20页
Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-t... Conductive elastomers combining micromechanical sensitivity,lightweight adaptability,and environmental sustainability are critically needed for advanced flexible electronics requiring precise responsiveness and long-term wearability;however,the integration of these properties remains a significant challenge.Here,we present a biomass-derived conductive elastomer featuring a rationally engineered dynamic crosslinked network integrated with a tunable microporous architecture.This structural design imparts pronounced micromechanical sensitivity,an ultralow density(~0.25 g cm^(−3)),and superior mechanical compliance for adaptive deformation.Moreover,the unique micro-spring effect derived from the porous architecture ensures exceptional stretchability(>500%elongation at break)and superior resilience,delivering immediate and stable electrical response under both subtle(<1%)and large(>200%)mechanical stimuli.Intrinsic dynamic interactions endow the elastomer with efficient room temperature self-healing and complete recyclability without compromising performance.First-principles simulations clarify the mechanisms behind micropore formation and the resulting functionality.Beyond its facile and mild fabrication process,this work establishes a scalable route toward high-performance,sustainable conductive elastomers tailored for next-generation soft electronics. 展开更多
关键词 Bio-based conductive elastomers Dynamic covalent chemistry Micromechanical sensitivity Soft electronics
在线阅读 下载PDF
Unraveling the role of ufmylation in the brain
4
作者 Rita J.Serrano Robert J.Bryson-Richardson 《Neural Regeneration Research》 2026年第2期667-668,共2页
Ufmylation is an ubiquitin-like post-translational modification characterized by the covalent binding of mature UFM1 to target proteins.Although the consequences of ufmylation on target proteins are not fully understo... Ufmylation is an ubiquitin-like post-translational modification characterized by the covalent binding of mature UFM1 to target proteins.Although the consequences of ufmylation on target proteins are not fully understood,its importance is evident from the disorders resulting from its dysfunction.Numerous case reports have established a link between biallelic loss-of-function and/or hypomorphic variants in ufmylation-related genes and a spectrum of pediatric neurodevelopmental disorders. 展开更多
关键词 target proteins post translational modification pediatric neurodevelopmental disorders covalent binding mature ufm target proteinsalthough biallelic loss function ufmylation hypomorphic variants neurodevelopmental disorders
暂未订购
Covalence bridge atomically precise metal nanocluster and metalorganic frameworks for enhanced photostability and photocatalysis 被引量:1
5
作者 Aimin Yao Yuanxin Du +5 位作者 Meng Han Yan Wang Jiashen Hu Qingtao Zhu Hongting Sheng Manzhou Zhu 《Nano Research》 SCIE EI CSCD 2023年第1期1527-1532,共6页
Metal nanoclusters(NCs)with precise structure and ultrasmall size have attracted great interests in catalysis.However,the poor stability has limited its large-scale use.Herein,we proposed the“covalence bridge”strate... Metal nanoclusters(NCs)with precise structure and ultrasmall size have attracted great interests in catalysis.However,the poor stability has limited its large-scale use.Herein,we proposed the“covalence bridge”strategy to effectively connect atomically precise metal NCs and metal-organic frameworks.Benefiting from the covalent linkage,the synthesized UiO-66-NH2-Au25(LCys)18 showed outstanding stability after 16 h photocatalysis.Moreover,the covalence bridge created a strong metal-support interaction between the two components and provided an effective charge transport channel and thereby enhanced photocatalytic activity.UiO-66-NH2-Au25(L-Cys)18 displayed an exceptional photocatalytic H2 production rate,which is 21 and 90 times higher than that of UiO-66-NH2/Au25(PET)18(made by physically combination)and bare UiO-66-NH2,respectively.Thermodynamic and kinetic studies demonstrated that UiO-66-NH2-Au25(L-Cys)18 exhibited higher charge transfer efficiency,lower overpotential of water reduction and activation energy barrier compared with its counterparts. 展开更多
关键词 atomically precise nanoclusters metal-organic frameworks covalent binding PHOTOSTABILITY photocatalytic hydrogen production
原文传递
Bond engineering:weakening Ru-O covalency for efficient and stable water oxidation in acidic solutions 被引量:3
6
作者 Yifan Yang Jingtong Guo +4 位作者 Lixiong Xu Chenyue Li Rongqian Ning Jun Ma Shuo Geng 《Journal of Energy Chemistry》 2025年第3期1-9,共9页
The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has ... The persistent stability of ruthenium dioxide(RuO_(2))in acidic oxygen evolution reactions(OER)is compromised by the involvement of lattice oxygen(LO)and metal dissolution during the OER process.Heteroatom doping has been recognized as a viable strategy to foster the stability of RuO_(2)for acidic OER applications.This study presented an ion that does not readily gain or lose electrons,Ba^(2+),into RuO_(2)(Ba-RuO_(2))nanosheet(NS)catalyst that increased the number of exposed active sites,achieving a current density of 10 mA/cm^(2)with an overpotential of only 229 mV and sustaining this output for over 250 h.According to density functional theory(DFT)and X-ray absorption spectroscopy,Ba doping resulted in a longer Ru-O bond length,which in turn diminished the covalency of the bond.This alteration curtailed the involvement of LO and the dissolution of ruthenium(Ru),thereby markedly improving the durability of the catalyst over extended periods.Additionally,attenuated total reflectance-surface enhanced infrared absorption spectroscopy analysis substantiated that the OER mechanism shifted from a LO-mediated pathway to an adsorbate evolution pathway due to Ba doping,thereby circumventing Ru over-oxidation and further enhancing the stability of RuO_(2).Furthermore,DFT findings uncovered that Ba doping optimizes the adsorption energy of intermediates,thus enhancing the OER activity in acidic environments.This study offers a potent strategy to guide future developments on Ru-based oxide catalysts'stability in an acidic environment. 展开更多
关键词 Oxygen evolution reaction in acid Bond covalency Rutheniumoxide Ba doping
在线阅读 下载PDF
Pyridine-nitrogen conjugated covalent organic frameworks for high-efficiency gas-solid photocatalytic reduction of CO_(2)to CO 被引量:2
7
作者 Haicheng Jiang Chi Cao +10 位作者 Wei Liu Hao Zhang Qianyu Li Siyuan Zhu Xiaoning Li Jinshuo Li Jinfa Chang Wei Hu Zihao Xing Xiaoqin Zou Guangshan Zhu 《Journal of Energy Chemistry》 2025年第5期127-135,共9页
The light-driven CO_(2)reduction reaction(CO_(2)RR)to CO is a very effective way to address global warming.To avoid competition with water photolysis,metal-free gas-solid CO_(2)RR catalysts should be investigated.Cova... The light-driven CO_(2)reduction reaction(CO_(2)RR)to CO is a very effective way to address global warming.To avoid competition with water photolysis,metal-free gas-solid CO_(2)RR catalysts should be investigated.Covalent organic frameworks(COFs)offer a promising approach for CO_(2)transformation but lack high efficiency and selectivity in the absence of metals.Here,we have incorporated a pyridine nitrogen component into the imine-COF conjugated structure(Tp Pym).This innovative system has set a record of producing a CO yield of 1565μmol g^(-1)within 6 h.The soft X-ray absorption fine structure measurement proves that Tp Pym has both better conjugation and electron cloud enrichment.The electronic structure distribution delays the charge-carrier recombination,as evidenced by femtosecond transient absorption spectroscopy.The energy band diagram and theoretical calculation show that the conduction-band potential of Tp Pym is lower and the reduction reaction of CO_(2)to CO is more likely to occur. 展开更多
关键词 Light-driven CO_(2)reduction Gas-solid reaction Conjugated pyridine nitrogen Covalent organic framework CO_(2)catalysis to CO
在线阅读 下载PDF
Superelastic and ultralight covalent organic framework composite aerogels modified with different functional groups for ultrafast adsorbing organic pollutants in water 被引量:1
8
作者 Shiyan Ai Yaning Xu +3 位作者 Hui Zhou Ziwei Cui Tiantian Wu Dan Tian 《Chinese Chemical Letters》 2025年第10期478-487,共10页
Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreo... Covalent organic frameworks(COFs)have great potential as adsorbents due to their customizable functionality,low density and high porosity.However,COFs powder exists with poor processing and recycling performance.Moreover,due to the accumulation of COFs nanoparticles,it is not conducive to the full utilization of their surface functional groups.Currently,the strategy of COFs assembling into aerogel can be a good solution to this problem.Herein,we successfully synthesize composite aerogels(CSR)by in-situ self-assembly of two-dimensional COFs and graphene based on crosslinking of sodium alginate.Sodium alginate in the composite improves the mechanical properties of the aerogel,and graphene provides a template for the in-situ growth of COFs.Impressively,CSR aerogels with different COFs and sizes can be prepared by changing the moiety of the ligand and modulating the addition amount of COFs.The prepared CSR aerogels exhibit porous,low density,good processability and good mechanical properties.Among them,the density of CSR-N-1.6 is only 5 mg/cm3,which is the lowest density among the reported COF aerogels so far.Due to these remarkable properties,CSR aerogels perform excellent adsorption and recycling properties for the efficient and rapid removal of organic pollutants(organic dyes and antibiotics)from polluted water.In addition,it is also possible to visually recognize the presence of antibiotics by fluorescence detection.This work not only provides a new strategy for synthesizing COF aerogels,but also accelerates the practical application of COF aerogels and contributes to environmental remediation. 展开更多
关键词 Covalent organic frameworks GRAPHENE AEROGELS ADSORPTION Sewage treatment
原文传递
Radiation reduction modification of sp^(2) carbon-conjugated covalent organic frameworks for enhanced photocatalytic chromium(Ⅵ) removal 被引量:1
9
作者 Shouchao Zhong Yue Wang +6 位作者 Mingshu Xie Yiqian Wu Jiuqiang Li Jing Peng Liyong Yuan Maolin Zhai Weiqun Shi 《Chinese Chemical Letters》 2025年第5期277-282,共6页
A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for ... A sp^(2) carbon-conjugated covalent organic framework (BDATN) was modified through γ-ray radiation reduction and subsequent acidification with hydrochloric acid to yield a novel functional COF (named rBDATN-HCl) for Cr(Ⅵ) removal.The morphology and structure of rBDATN-HCl were analyzed and identified by SEM,FTIR,XRD and solid-state13C NMR.It is found that the active functional groups,such as hydroxyl and amide,were introduced into BDATN after radiation reduction and acidification.The prepared rBDATN-HCl demonstrates a photocatalytic reduction removal rate of Cr(Ⅵ) above 99%after 60min of illumination with a solid-liquid ratio of 0.5 mg/mL,showing outstanding performance,which is attributed to the increase of dispersibility and adsorption sites of r BDATN-HCl.In comparison to the cBDATN-HCl synthesized with chemical reduction,rBDATN-HCl exhibits a better photoreduction performance for Cr(Ⅵ),demonstrating the advantages of radiation preparation of rBDATN-HCl.It is expected that more functionalized sp^(2) carbon-conjugated COFs could be obtained by this radiation-induced reduction strategy. 展开更多
关键词 Covalent organic framework Gamma radiation Photocatalytic reduction CHROMIUM Water purification
原文传递
In situ preparation of zincophilic covalent-organic frameworks with low surface work function and high rigidity to stabilize zinc metal anodes 被引量:1
10
作者 Yunyu Zhao Kaiyong Feng Yingjian Yu 《Journal of Energy Chemistry》 2025年第3期524-533,共10页
Zinc-ion batteries(ZIBs)are inexpensive and safe,but side reactions on the Zn anode and Zn dendrite growth hinder their practical applications.In this study,1,3,5-triformylphloroglycerol(Tp)and various diamine monomer... Zinc-ion batteries(ZIBs)are inexpensive and safe,but side reactions on the Zn anode and Zn dendrite growth hinder their practical applications.In this study,1,3,5-triformylphloroglycerol(Tp)and various diamine monomers(p-phenylenediamine(Pa),benzidine(BD),and 4,4"-diamino-p-terphenyl(DATP))were used to synthesize a series of two-dimensional covalent-organic frameworks(COFs).The resulting COFs were named TpPa,TpBD,and TpDATP,respectively,and they showed uniform zincophilic sites,different pore sizes,and high Young's moduli on the Zn anode.Among them,TpPa and TpBD showed lower surface work functions and higher ion transfer numbers,which were conducive to uniform galvanizing/stripping zinc and inhibited dendrite growth.Theoretical calculations showed that TpPa and TpBD had wider negative potential region and greater adsorption capacity for Zn2+than TpDATP,providing more electron donor sites to coordinate with Zn^(2+).Symmetric cells protected by TpPa and TpBD stably cycled for more than 2300 h,whereas TpDATP@Zn and the bare zinc symmetric cells failed after around 150 and200 h.The full cells containing TpPa and TpBD modification layers also showed excellent cycling capacity at 1 A/g.This study provides comprehensive insights into the construction of highly reversible Zn anodes via COF modification layers for advanced rechargeable ZIBs. 展开更多
关键词 Zn ion batteries Covalent organic framework DENDRITE Low surface work function High rigidity
在线阅读 下载PDF
Amorphous-rich RuMnO_(x)aerogel with weakened Ru–O covalency for efficient acidic water oxidation 被引量:1
11
作者 Tao Zhao Yunzhen Jia +7 位作者 Qiang Fang Runxin Du Genyan Hao Wenqing Sun Guang Liu Dazhong Zhong Jinping Li Qiang Zhao 《Journal of Energy Chemistry》 2025年第5期414-421,共8页
Ruthenium dioxide(RuO_(2))is one of the most promising acidic oxygen evolution reaction(OER)catalysts to replace the expensive and prevalent iridium(Ir)-based materials.However,the lattice oxygen oxidation induced Ru ... Ruthenium dioxide(RuO_(2))is one of the most promising acidic oxygen evolution reaction(OER)catalysts to replace the expensive and prevalent iridium(Ir)-based materials.However,the lattice oxygen oxidation induced Ru dissolution during OER compromises the activity and stability.Amorphous materials have been identified as a viable strategy to promote the stability of RuO_(2)in acidic OER applications.This study reported a nanoporous amorphous-rich RuMnO_(x)(A-RuMnO_(x))aerogel for efficient and stable acidic OER.Compared with highly crystalline RuMnO_(x),the weakened Ru–O covalency of A-RuMnO_(x)by forming amorphous structure is favorable to inhibiting the oxidation of lattice oxygen.Meanwhile,this also optimizes the electronic structure of Ru sites from overoxidation and reduces the reaction energy barrier of the rate-determining step.As a result,A-RuMnO_(x)aerogel exhibits an ultra-low overpotential of 145 mV at 10 mA cm^(-2)and durability exceeding 100 h,as well as high mass activity up to 153 mA mg^(-1)_(Ru)at 1.5 V vs.reversible hydrogen electrode(RHE).This work provides valuable guidance for preparing highly active and stable Ru-based catalysts for acidic OER. 展开更多
关键词 ELECTROCATALYST A-RuMnO_(x)aerogel Amorphous structure COVALENCY Acidic oxygen evolution reaction
在线阅读 下载PDF
Constructing Donor–Acceptor‑Linked COFs Electrolytes to Regulate Electron Density and Accelerate the Li^(+)Migration in Quasi‑Solid‑State Battery
12
作者 Genfu Zhao Hang Ma +5 位作者 Conghui Zhang Yongxin Yang Shuyuan Yu Haiye Zhu Yongjiang Sun Hong Guo 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期456-471,共16页
Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal batteries.This study reports a high-... Regulation the electronic density of solid-state electrolyte by donor–acceptor(D–A)system can achieve highly-selective Li^(+)transportation and conduction in solid-state Li metal batteries.This study reports a high-performance solid-state electrolyte thorough D–A-linked covalent organic frameworks(COFs)based on intramolecular charge transfer interactions.Unlike other reported COFbased solid-state electrolyte,the developed concept with D–A-linked COFs not only achieves electronic modulation to promote highly-selective Li^(+)migration and inhibit Li dendrite,but also offers a crucial opportunity to understand the role of electronic density in solid-state Li metal batteries.The introduced strong electronegativity F-based ligand in COF electrolyte results in highlyselective Li^(+)(transference number 0.83),high ionic conductivity(6.7×10^(-4)S cm^(−1)),excellent cyclic ability(1000 h)in Li metal symmetric cell and high-capacity retention in Li/LiFePO_(4)cell(90.8%for 300 cycles at 5C)than substituted C-and N-based ligands.This is ascribed to outstanding D–A interaction between donor porphyrin and acceptor F atoms,which effectively expedites electron transferring from porphyrin to F-based ligand and enhances Li^(+)kinetics.Consequently,we anticipate that this work creates insight into the strategy for accelerating Li^(+)conduction in high-performance solid-state Li metal batteries through D–A system. 展开更多
关键词 Electronic modulation engineering Donor-acceptor-linked covalent organic frameworks Quasi-solid-state Li metal battery
在线阅读 下载PDF
Recyclable and Self-healable Polydimethylsiloxane Elastomers Based on Knoevenagel Condensation
13
作者 Yao-Wei Zhu Tong-Tong Man +5 位作者 Ming-Ming Zhao Jia-Yi Chen Yu Yan Xiao-Nong Zhang Li Chen Chun-Sheng Xiao 《Chinese Journal of Polymer Science》 2025年第1期53-60,I0007,共9页
Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that ... Elastomers are widely used in various fields owing to their excellent tensile properties.Recyclable and self-healing properties are key to extending the service life of elastomers.Accumulating evidence indicates that dynamic covalent chemistry has emerged as a powerful tool for constructing recyclable and self-healing materials.In this work,we demonstrate the preparation of a recyclable and self-healable polydimethylsiloxane(PDMS)elastomer based on the Knoevenagel condensation(KC)reaction.This PDMS elastomer was prepared by the KC reaction catalyzed by 4-dimethylaminopyridine(DMAP).The obtained PDMS elastomer exhibited an elongation at break of 266%,a tensile strength of 0.57 MPa,and a good thermal stability(Td=357℃).In addition,because of the presence of dynamic C=C bonds formed by the KC reaction and low glass transition temperature(Tg=-117℃).This PDMS exhibited good self-healing and recycling properties at room temperature and could be reprocessed by hot pressing.In addition,the PDMS elastomer exhibits good application prospects in the fields of adhesives and flexible electronic devices. 展开更多
关键词 Dynamic covalent chemistry ELASTOMER Knoevenagel condensation reaction POLYDIMETHYLSILOXANE RECYCLABLE SELF-HEALING
原文传递
Design of Weldable and Recyclable Fluorine-containing Adhesives Utilizing Dynamic-covalent Boroxine Bonds
14
作者 Hou-Li Zhang Yu-Quan Sun +6 位作者 Yao Xu Lu Wang Ying Li Jie Zhang Bing Geng Shu-Sheng Li Chuan-Yong Zong 《Chinese Journal of Polymer Science》 2025年第8期1433-1442,共10页
The advancement of functional adhesives featuring recyclable and repairable properties is of great significance in interfacial science and engineering.Herein,a series of high-strength,recyclable fluorine-containing ad... The advancement of functional adhesives featuring recyclable and repairable properties is of great significance in interfacial science and engineering.Herein,a series of high-strength,recyclable fluorine-containing adhesives(ESOx-FPF)were designed and synthesized by crosslinking two prepolymers,FPF-B(derived from side-chain fluorinated diol,isocyanate,and aminoboric acid)and ESO-B(synthesized from biobased epoxy soybean oil and aminoboric acid),through dynamic boro-oxygen bonds.The resulting adhesive exhibited an optimal tensile strength of 42 MPa and the shear strength on steel plates reached as high as 3.89 MPa.More importantly,benefiting from the dynamic reversibility of the boron-oxygen bonds along with the hydrogen bonds interaction,ESOx-FPF can be welded with the assistance of solvents and recycled for multiple cycles.The outstanding healing efficiency and excellent reprocessability of these functional adhesives were confirmed by mechanical testing.Moreover,the as-prepared adhesives demonstrated universal and remarkable adhesion to various substrates,such as aromatic polyamide,aluminum plates and polycarbonate,meanwhile,they could be easily disassembled and recycled using ethanol without damaging the substrates surface.This study not only provides a simple strategy for the synthesis of eco-friendly adhesives with weldable and recyclable properties,but also sheds light on the development of other functional materials utilizing dynamic covalent chemistry. 展开更多
关键词 Functional adhesive RECYCLABLE Dynamic covalent bonds Boroxines FLUORINE-CONTAINING
原文传递
Periodic Janus structure based on ionic covalent organic framework for selective removal of perfluoroalkyl substances
15
作者 Xiaojuan Sun Ke Kong +3 位作者 Jun Liang Dan Wang Beibei Dong Ruihu Wang 《Chinese Journal of Structural Chemistry》 2025年第9期14-19,共6页
Per-and polyfluoroalkyl substances(PFAS)are persistent environmental contaminants that often show an adverse impact on human health.Rational design of porous adsorbents for selective and reversible removal of PFAS,suc... Per-and polyfluoroalkyl substances(PFAS)are persistent environmental contaminants that often show an adverse impact on human health.Rational design of porous adsorbents for selective and reversible removal of PFAS,such as perfluorooctane sulfonate(PFOS),is imperative and challenging.Herein,a Janus strategy based on an ionic covalent organic framework(iCOF-DGCl)composed of the alternately hydrophobic aromatic domains and hydrophilic guanidinium moieites has been proposed to meet the requirement of high-performance adsorbents.iCOF-DGCl shows fast adsorption kinetics(970.9 mg g^(−1)min^(−1))and ultrahigh uptake capacity(2491 mg g^(−1))toward PFOS,making it one of the most effective materials among the reported PFOS adsorbents.Moreover,the PFOS removal by iCOF-DGCl remains highly selective in the presence of disturbing anions,and the adsorbent could be well recovered for reuse.Mechanism studies have demonstrated that the Janus structure units of iCOF-DGCl form both hydrophobic and electrostatic interactions with the amphiphilic PFOS,thus achieving cooperative adsorption of PFOS.This work provides a facile approach based on Janus structure of COFs adsorbent for wastewater remediation. 展开更多
关键词 Covalent organic framework Ionic polymer Perfluorooctane sulfonate Adsorption ADSORBENT
原文传递
Tumor-responsive covalent organic polymeric nanoparticles enhancing STING activation for cancer immunotherapy
16
作者 Shuang Liang Jianjun Yao +3 位作者 Dan Liu Mengli Zhou Yong Cui Zhaohui Wang 《Chinese Chemical Letters》 2025年第3期357-362,共6页
The cyclic guanosine monophosphate-adenosine monophosphate synthase and the stimulator of interferon genes(cGAS-STING)has emerged as a promising target for cancer immunotherapy.However,the development of natural STING... The cyclic guanosine monophosphate-adenosine monophosphate synthase and the stimulator of interferon genes(cGAS-STING)has emerged as a promising target for cancer immunotherapy.However,the development of natural STING agonists is impeded by several challenges,including limited biostability,poor pharmacokinetics,and inefficient cytosolic delivery.Herein,we meticulously designed a doublelayer polyethylenimine(PEI)modified nanoscale covalent organic polymer(CPGP)for efficient delivery of 23cyclic guanosine monophosphate-adenosine monophosphate(cGAMP),a natural STING agonist.The double-layer PEI structured CPGP enhanced both the loading capacity and stability of cGAMP.Furthermore,CPGP improved the intracellular delivery efficiency and amplified the activation of STING pathway for the secretion of type-I interferon and pro-inflammatory cytokines.In contrast,single-layered nanoparticles failed to permit stable loading and intracellular delivery of cGAMP for immune response.The nano-STING agonist also mitigated the immunosuppressive tumor microenvironment(TME)by reducing regulatory T cells and polarizing M2 macrophages to the M1 phenotype,thereby creating an immune-supportive TME to enhance adaptive immune responses.The combination of CPGP and immune checkpoint blockers showed synergistic effect,further enhancing the inhibition effect on tumor growth.This double-layer PEI modified CPGP may offer a generalizable platform for other natural dinucleotide STING agonists to overcome the cascade delivery barriers,augmenting immune activation for tumor immunotherapy. 展开更多
关键词 IMMUNOTHERAPY Covalent organic polymers Delivery STING agonists NANOPARTICLE
原文传递
Regulating local electron transfer environment of covalent triazine frameworks through F,N co-modification towards optimized oxygen reduction reaction
17
作者 Quanyou Guo Yue Yang +6 位作者 Tingting Hu Hongqi Chu Lijun Liao Xuepeng Wang Zhenzi Li Liping Guo Wei Zhou 《Chinese Chemical Letters》 2025年第1期344-348,共5页
The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalyt... The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalytic active center.Therefore,the electronic conductivity is a vital parameter for oxygen reduction reaction(ORR).Covalent triazine frameworks(CTFs)have shown great potential application as electrocatalysts in ORR with a merit of the diverse building blocks.However,the intrinsic low conductivity and high impedance of CTFs could be significant setbacks in electrocatalytic application.Herein,CTFs were constructed by introducing F and N co-modification for efficient 2e^(-)ORR.Compared with the pristine CTF,the co-presence of F,N could increase the conductivity obviously by 1000-fold.As a result,F-N-CTF exhibits enhanced catalytic performance of H_(2)O_(2)generation and selectivity towards reaction pathways.This work reveals the importance of conductivity optimization for CTFs and provides guidance for designing high conductivity non-metallic organic semiconductor catalysts for 2e^(-)ORR. 展开更多
关键词 Covalent triazine frameworks CONDUCTIVITY Co-modification ELECTROCATALYSIS Oxygen reduction reaction
原文传递
Construction of NiS/CTF heterojunction photocatalyst with an outstanding photocatalytic hydrogen evolution performance
18
作者 Tao Zhou Xu Han +4 位作者 Wangwang Shen Fang Ji Menglong Liu Yingyu Song Wen-Wen He 《Chinese Chemical Letters》 2025年第11期478-482,共5页
Heterojunction engineering is considered as one of the most effective methods to improve the hydrogen production performance of photocatalysts.In this study,a green,simple and gentle method was used to deposit tiny Ni... Heterojunction engineering is considered as one of the most effective methods to improve the hydrogen production performance of photocatalysts.In this study,a green,simple and gentle method was used to deposit tiny Ni S onto CTF-ES_(200)under xenon lamp irradiation to form heterostructures.The experimental results show that the hydrogen production rate of the synthesized Ni S/CTF-ES_(200)is as high as 22.98mmol g^(-1)h^(-1),showing a higher photocatalytic hydrogen production rate compared to other Ni S-loaded nonmetallic semiconductor materials,which is also much higher than that of pure CTF-ES_(200).The interface electric field(IEF)in this p-n heterojunction leads to an accumulation of photoelectrons on the conduction band of CTF-ES_(200),which makes CTF-ES_(200)to keep a high reductiveness for the hydrogen evolution reaction(HER),and significantly improve the separation efficiency of photoelectrons and holes.Furthermore,XPS and EXAFS data show that an efficient electron transport channel is constructed through the formation of Ni-N bond,which further accelerates the interface carrier transport efficiency.This study provides an effective idea for the preparation of highly efficient heterojunction photocatalysts. 展开更多
关键词 NIS Covalent triazine frameworks PHOTODEPOSITION HETEROJUNCTION Photocatalytic hydrogen evolution
原文传递
Facile scalable fabrication of triazine-based flexible covalent organic framework fiber film with multifunction at room temperature
19
作者 Huimin Yan Yan Kou +4 位作者 Jiao Wang Shihui Zhang Nan Yin Wenhao Cui Quan Shi 《Journal of Energy Chemistry》 2025年第9期410-416,I0012,共8页
Flexible covalent organic framework(COF)film has drawn much attention as a promising functional material due to their unique molecular structure and self-supporting property.However,the traditional solvothermal method... Flexible covalent organic framework(COF)film has drawn much attention as a promising functional material due to their unique molecular structure and self-supporting property.However,the traditional solvothermal method of synthesizing flexible COF film is usually complicated,long-term duration and energy-consuming,making it unsuitable for scalable preparation.To address these limitations,a new method combining electrospinning and sacrificial template is proposed to quickly produce triazinebased COF fiber films at room temperature.The method is easy to operate and has a short reaction time(minimum 0.5 h)without dehydration and deoxygenation processes at room temperature,making it suitable for large-scale production(20 cm×30 cm).Different from the unprocessable of COF powder,COF films not only have good flexibility and mechanical properties,but also can be patterned with multiple functions to adapt to various application scenarios.Moreover,the functionality of triazine-structured COF is retained,enabling the use of the films in energy conversion and storage applications.Triazine-based COFs naturally have scalable conjugated structure,thus showing potential photocatalytic probability.Furthermore,the large pore structure of COF films enables loading of phase change materials endowing comprehensive properties of thermal management and flame retardance.This study proposes a strategy for the rapid synthesis of COF fiber films at room temperature and paves the way for multifunctional and high-performance COF based materials. 展开更多
关键词 Covalent organic frameworks ELECTROSPINNING Photocatalysis Flame retardant Thermal management
在线阅读 下载PDF
Multi-metal porous crystalline materials for electrocatalysis applications
20
作者 Ming Yue Yi-Rong Wang +7 位作者 Jia-Yong Weng Jia-Li Zhang Da-Yu Chi Mingjin Shi Xiao-Gang Hu Yifa Chen Shun-Li Li Ya-Qian Lan 《Chinese Chemical Letters》 2025年第6期249-263,共15页
Multi-metal porous crystalline materials(MPCM),integrating the functions of both multi-metal centres and porous crystalline materials(e.g.,metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)),are an ex... Multi-metal porous crystalline materials(MPCM),integrating the functions of both multi-metal centres and porous crystalline materials(e.g.,metal-organic frameworks(MOFs)and covalent organic frameworks(COFs)),are an extended class of porous materials that have attracted much attention for a broad range of applications.Owing to the advantages of these materials,they generally display high porosity,multimetal active sites,well-tuned functions,and pre-designable structures,etc.,serving as desired platforms for the study of structure-property relationships.In view of the clean and sustainable target,a series of MPCM have been explored as electrocatalysts for electrocatalytic reactions like hydrogen evolution reaction,oxygen evolution reaction and electrocatalytic CO_(2)reduction reaction.Concerning the progress achieved for MPCM in electrocatalytic field during past years,this review will provide a brief introduction on the recent breakthrough of MPCM based electrocatalysts including their synthesis methods,structure design,component/morphology tuning,electrocatalytic property and structure-property relationship,etc.Besides,it will also conclude the current challenges and present perspectives for the MPCM based electrocatalysts,which might promote the development of porous crystalline materials in electrocatalysis and hope to provide new insights for scientists in related fields. 展开更多
关键词 Porous crystalline materials Multi-metal Metal-organic frameworks Covalent organic frameworks ELECTROCATALYSIS
原文传递
上一页 1 2 46 下一页 到第
使用帮助 返回顶部