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Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

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Nano Research 2024年第6期17卷 4825-4833页

作者： Kai-Kai Niu Chao-Qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng Yu Ling-Bao Xing school of chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

Compositional evolution for mixed aerosols containing gluconic acid and typical nitrate and the effect of multiply factors on hygroscopicity

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Journal of Environmental Sciences 2024年第5期139卷 206-216页

作者： Yue Zhu Shufeng Pang Yunhong Zhang school of chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China

The aging process of atmospheric aerosols usually leads to a mixture of inorganic salts and organic compounds of anthropogenic *** organic compounds,polyhydroxy organic acids are important components,however,the study on composition and hygroscopic properties of the mixture containing inorganics and polyhydroxy organic acids is *** this study,gluconic acid,the proxy of polyhydroxy organic acids,is mixed with the representative nitrate(Mg(NO_(3))_(2),Ca(NO_(3))_(2))to form ***-FTIR and optical microscopy are employed to study the component changes and hygroscopicity as a function of relative *** relative humidity fluctuates,the FTIR-ATR spectra display that the internal mixed gluconic acid(CH_(2)(CH)_(4)(OH)_(5)COOH)and nitrate can react to release acidic gases,forming relevant gluconate and further affecting the *** specific presentation is particles cannot be recovered to their original size after the dehydration-hydration process and there will be some disparities in GF for mixed *** the gluconic acid-Ca(NO_(3))_(2)/Mg(NO_(3))_(2)mixtures with molar ratios of 1:1,higher degree of reaction resulting in the production of large amounts of gluconate should be responsible to the lower hygroscopicity compared to ZSR *** 1:2 gluconic acid-nitrate mixed systems(with higher nitrate content),the hygroscopicity of mixtures are higher than the ZSR prediction.A possible reason could be‘salt-promoting effect’on the organic fractions of the surplus inorganic salt in the *** data can improve the chemical composition list evaluation,in turn hygroscopic properties and phase state of atmospheric aerosol,and then the climate effect.

关键词： Hygroscopicity Gluconic acid Reaction ZSR simulation Size growth factors

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Enhanced conductivity and stability of Prussian blue cathodes in sodium-ion batteries by surface vapor-phase molecular selfassembly

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Nano Research 2024年第5期17卷 4221-4230页

作者： Tao Yuan Xiaopan Fu Yuan Wang Mingjie Li Shuixin Xia Yuepeng Pang Shiyou Zheng school of Materials and chemistry University of Shanghai for Science and TechnologyShanghai 200093China

With many merits such as facile synthesis,economy,and relatively high theoretical capacity,Prussian blue analogs(PBAs)are considered promising cathode materials for sodium-ion batteries(SIBs).However,their practical applications still suffer from a low actual specific capacity and inferior stability owing to the imperfect crystallinity,irreversible phase transition,and low intrinsic ***,a surface-modification technique for vapor-phase molecular self-assembly was developed to prepare Fe-based PBAs,specifically sodium iron hexacyanoferrate(NaFeHCF),with a uniform conductive polymer protective layer of polypyrrole(PPy)on the surface,resulting in NaFeHCF@*** incorporation of a PPy protective layer not only improves the electronic conductivity of NaFeHCF@PPy,but also effectively mitigates the dissolution of Fe-ions during ***,this advanced vapor-phase technique avoids Fe^(2+)oxidation and Na^(+)loss during liquid-phase surface *** NaFeHCF@PPy exhibited a remarkably enhanced cycling performance,with capacity retentions of 85.6%and 69.1%over 500 and 1000 cycles,respectively,at 200 mA/g,along with a superior rate performance up to 5 A/g(fast kinetics).Additionally,by adopting this strategy for Mn-based PBAs(NaMnHCF@PPy),we further demonstrated the universality of this method for PBA cathodes in SIBs.

关键词： sodium-ion battery cathode Prussian blue analogs surface modification vapor-phase molecular self-assembly

Enhanced photocatalytic performance by regulating the Ce^(3+)/Ce^(4+)ratio in cerium dioxide

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Frontiers of Chemical Science and Engineering 2024年第3期18卷 75-87页

作者： Zhi Li Dongsheng Jia Wei Zhang Ying Li Mitang Wang Dongliang Zhang school of Materials and chemistry University of Shanghai for Science and TechnologyShanghai200093China

Cerium dioxide(CeO_(2))photocatalysts are used in treating environmental pollution and addressing the energy crisis due to their excellent oxygen storage capacities and abundant oxygen *** this paper,CeO_(2)precursors were synthesized with different water-alcohol ratios via a solvothermal method,and CeO_(2)photocatalysts with different Ce^(3+)/Ce^(4+)ratios were obtained by changing the precursor calcination atmospheres(air,Ar)as well as the calcination *** effects of CeO_(2)with different Ce^(3+)/Ce^(4+)ratios in photocatalytic degradations of methylene blue under visible light were investigated.X-ray photoelectron spectroscopy results showed that the surfaces of the samples calcined under Ar had higher Ce^(3+)/Ce^(4+)ratios and oxygen vacancy concentrations,which reduced the band gaps of the catalysts and improved their utilization of visible *** addition,the many Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies on the sample surfaces improved the separation and transfer efficiencies of the photogenerated *** sample C2-Ar calcined under Ar showed a high adsorption capacity and excellent photocatalytic activity by removing 96%of the methylene blue within 120 min,which was more than twice the degradation rate of the sample(C2-air)prepared via calcination under *** experiments showed that photogenerated holes played a key role in the photocatalytic *** addition,a synergistic photocatalytic mechanism for the Ce^(3+)/Ce^(4+)redox centers and oxygen vacancies was elucidated in detail,and the sensitization of cerium dioxide by dyes aided the degradation of methylene blue.

关键词： CeO_(2) oxygen vacancies Ce^(3+)/Ce^(4+)ratios photocatalytic dye-sensitization

Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis

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National Science Review 2024年第7期11卷 177-188页

作者： Tian-Tian Ma Guo-Zhang Huang Xiao-Han Wang Yan Liang Run-Han Li Bin Wang Su-Juan Yao Jia-Peng Liao Shun-Li Li Yong Yan Ya-Qian Lan school of chemistry South China Normal University Department of chemistry Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology

Covalent-organic frameworks（COFs） with photoinduced donor-acceptor（D-A） radical pairs show enhanced photocatalytic activity in principle. However, achieving long-lived charge separation in COFs proves challenging due to the rapid charge recombination. Here, we develop a novel strategy by combining[6 + 4] nodes to construct zyg-type 3D COFs, first reported in COF chemistry. This structure type exhibits a fused Olympic-rings-like shape, which provides a platform for stabilizing the photoinduced D-A radical pairs. The zyg-type COFs containing catalytically active moieties such as triphenylamine and phenothiazine（PTZ） show superior photocatalytic production rates of hydrogen peroxide（H2O2）. Significantly, the photochromic radical states of these COFs show up to 400% enhancement in photocatalytic activity compared to the parent states, achieving a remarkable H2O2synthesis rate of 3324 μmol g-1h-1, which makes the PTZ-COF one of the best crystalline porous photocatalysts in H2O2production. This work will shed light on the synthesis of efficient 3D COF photocatalysts built on topologies that can facilitate photogenerating D-A radical pairs for enhanced photocatalysis.

关键词： 3D covalent-organic frameworks photochromic radical states donor and acceptor hydrogen peroxide photocatalysis

One dimensional CeO_(2) nanorods/poly(ethylene oxide) solid composite electrolyte for all-solid-state lithium-ion batteries

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Journal of Rare Earths 2024年第3期42卷 570-577,I0005页

作者： Yudi Guo Erqing Zhao Xiaofang Zhao Shuailei Liu school of chemistry and Materials Engineering Xinxiang UniversityXinxiang453003China school of chemistry and Chemical Engineering Henan Institute of Science and TechnologyXinxiang453003China

The research of poly(ethylene oxide)(PEO)-based solid composite electrolyte with high ionic conductivity and excellent interfacial stability is the key to the development of all-solid-state lithium-ion batteries(ASSLIBs). Herein, uniform nanorod structured CeO_(2) fillers were controllably synthesized by electrospinning, which were subsequently filled into PEO polymer to prepare CeO_(2)/PEO solid composite electrolyte. The addition of CeO_(2) nanorods can reduce both the glass transition temperature and the melting point of PEO polymer, and also interact with PEO and lithium bis(trifluoromethanesulphonyl)imide(LITFSI) by Lewis acid—base reaction. Therefore, the solid composite electrolyte exhibits a high ionic conductivity of 4.52 × 10^(-4)S/cm, a wide electrochemical stability window of about 4.8 V, and a good interfacial stability with Li at 55℃. Moreover, the LiFePO_4/Li ASSLIB divulges the discharging specific capacity of 165, 162, 156 and 146 mA,h/g at 0.2, 0.5, 1 and 2 C, respectively, and achieves the capacity retention of 90.3% after 150 cycles at 0.5 C. Consequently, one dimensional CeO_(2) nanorods can be considered as an alternative filler for polymeric solid electrolyte.

关键词： Poly(ethylene oxide) Solid composite electrolyte CeO_(2)nanorods Ionic conductivity Rare earths

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Preparation of bifunctional electrocatalyst by recycling heavy metal ions from wastewater using EDTAD-functionalized MOF as highly efficient adsorbent

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Rare Metals 2024年第10期43卷 5105-5116页

作者： Yue Qian Pei-Xue Fu Rui-Ze Yin Han-Ni Yang Si-Yang Li Wei-Wei Xiong Fen-Fen Zheng Jun-Hao Zhang Ai-Hua Yuan Huan Pang school of Environmental and Chemical Engineering Jiangsu University of Science and Technology school of chemistry and Chemical Engineering Yangzhou University

The recovery and subsequent reuse of heavy metal ions from industrial wastewater are crucial for promoting sustainable development,but they also presen significant *** this article,ethylenediaminetetraacetic dianhydride （EDTAD）,which possesses strong metal chelating ability,is covalently attached to MIL-101-NH2（Fe）,resulting in a significant improvement in the removal rate of heavy metal ions in ***,the recovered waste metal ions are transformed into high-performance FeNi3/NiFe2O4@NC dual-functional oxygen evolution reaction （OER） and oxygen reduction reaction （ORR） ***,FeNi3/NiFe2O4@NC exhibits outstanding OER performance,with only a264 mV overpotential at 10 mA·*** functiona theory （DFT） calculations reveal that the synergistic effect of the FeNi3/NiFe2O4@NC heterostructure can enhance conductivity,optimize the free energy of*to OH*during OER reaction,and promote catalytic *** work not only improves the removal rate of heavy metal ions but also obtains high-performance catalysts,while providing a new approach for the treatment and secondary utilization of heavy metal ion wastewater as well as the preparation of low-cost catalysts.

关键词： Bifunctional electrocatalyst Covalently modified MOF Ethylenediaminetetraacetic dianhydride Heavy metals

Triphenylphosphine-Assisted Exsolution Engineering on Ruddlesden-Popper Perovskites for Promoting Oxygen Evolution

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Energy & Environmental Materials 2024年第4期7卷 433-441页

作者： Juan Bai Jing Shang Jun Mei Dongchen Qi Ting Liao Ziqi Sun school of chemistry and Physics Queensland University of Technology Centre for Materials Science Queensland University of Technology school of Materials Science and Engineering Shaanxi University of Science and Technology school of Mechanical Medical and Process Engineering Queensland University of Technology

Metal exsolution engineering has been regarded as a promising strategy for activating intrinsically inert perovskite oxide catalysts toward efficient oxygen evolution *** metal exsolution processes on perovskites are often achieved by using the reducing hydrogen gas; however,this is not effective for the relatively stable phase,such as Ruddlesden-Popper perovskite oxides.

关键词： exsolution oxygen evolution perovskite reconstruction Ruddlesden–Popper

Approaching the theoretical capacity of TiO_(2) anode in a photorechargeable lithium-ion battery

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Nano Research 2024年第4期17卷 2655-2662页

作者： Wen Yan Jie Wang Qing Hu Jingjing Fu Mohamed K.Albolkany Tian Zhang Xiao Lu Fei Ye Bo Liu school of chemistry and Materials Science University of Science and Technology of ChinaHefei 230026China

New generation of lithium-ion batteries(LIBs)integrating solar energy conversion and storage is emerging,as they could solve the fluctuation problem in the utilization of solar ***-rechargeable lithium-ion batteries(PR-LIBs)are ideal devices for such target,in which solar energy is converted into electricity and stored in *** order to achieve the high performance of PR-LIB,it is crucial to develop dual-function electrode materials that can synergistically capture solar energy and store ***,we present photo-rechargeable lithium-ion batteries using defective black TiO_(2) as photoanode prepared by lithium *** photoanode exhibits excellent photo response in full solar spectrum with a capacity enhancement of 46.4%under illumination,corresponding to the energy conversion efficiency of 4.4%at the current density of 1 A·g^(-1).When illumination is applied at 20 mA·g^(-1),the battery capacity increases from~230 in dark to~349 mAh·g^(-1) at the first cycle,and then stabilizes at 310 mAh·g^(-1),approaching the theoretical value of 335 mAh·g^(-1) of TiO_(2) electrode *** finding provides thoughts for breaking the capacity limitations in TiO_(2) and paves the way for powering LIBs by solar illumination.

关键词： photo-rechargeable lithium-ion batteries photoanode defective TiO_(2)(D-TiO_(2))