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Unlocking the potential of ultra-thin two-dimensional antimony materials:Selective growth and carbon coating for efficient potassium-ion storage
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作者 Dongyu Zhang Zhaomin Wang +4 位作者 Yabin Shen Yeguo Zou Chunli Wang Limin Wang Yong Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期440-449,共10页
Antimony-based anodes have attracted wide attention in potassium-ion batteries due to their high theoretical specific capacities(∼660 mA h g^(-1))and suitable voltage platforms.However,severe capacity fading caused b... Antimony-based anodes have attracted wide attention in potassium-ion batteries due to their high theoretical specific capacities(∼660 mA h g^(-1))and suitable voltage platforms.However,severe capacity fading caused by huge volume change and limited ion transportation hinders their practical applications.Recently,strategies for controlling the morphologies of Sb-based materials to improve the electrochemical performances have been proposed.Among these,the two-dimensional Sb(2D-Sb)materials present excellent properties due to shorted ion immigration paths and enhanced ion diffusion.Nevertheless,the synthetic methods are usually tedious,and even the mechanism of these strategies remains elusive,especially how to obtain large-scale 2D-Sb materials.Herein,a novel strategy to synthesize 2D-Sb material using a straightforward solvothermal method without the requirement of a complex nanostructure design is provided.This method leverages the selective adsorption of aldehyde groups in furfural to induce crystal growth,while concurrently reducing and coating a nitrogen-doped carbon layer.Compared to the reported methods,it is simpler,more efficient,and conducive to the production of composite nanosheets with uniform thickness(3–4 nm).The 2D-Sb@NC nanosheet anode delivers an extremely high capacity of 504.5 mA h g^(-1) at current densities of 100 mA g^(-1) and remains stable for more than 200 cycles.Through characterizations and molecular dynamic simulations,how potassium storage kinetics between 2D Sb-based materials and bulk Sb-based materials are explored,and detailed explanations are provided.These findings offer novel insights into the development of durable 2D alloy-based anodes for next-generation potassium-ion batteries. 展开更多
关键词 ANTIMONY Two-dimensional materials Selective growth Nitrogen-doped carbon Potassium-ion batteries
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High-performance ZIF-8 membranes:preparation and their uranium adsorption performance
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作者 CUI Shuaichuan DENG Ziqi +6 位作者 HUANG Yifan LIU Shihan WANG Xingxing CHEN Shusen LI Ziming ZHANG Yifan DENG Pengyang 《辐射研究与辐射工艺学报》 CAS CSCD 2024年第5期24-37,共14页
In this study,the ZIF-8 membrane(ZIF-8/PP-g-MAH)is prepared by in situ synthesis of ZIF-8 on irradiation-pretreated polymer substrates to improve the uranium adsorption performance and address the recycling problems o... In this study,the ZIF-8 membrane(ZIF-8/PP-g-MAH)is prepared by in situ synthesis of ZIF-8 on irradiation-pretreated polymer substrates to improve the uranium adsorption performance and address the recycling problems of ZIF-8 powder.The effects of pH,contact time,and uranium concentration on the adsorption of ZIF-8/PP-g-MAH were investigated.Adsorption isotherm and kinetics analysis show that ZIF-8/PP-g-MAH has a high adsorption capacity of 478.5 mg/g,which is 1.26 times higher than that of ZIF-8,and a rapid adsorption equilibrium of 120 min,which is shortened to one-third of that required for ZIF-8(360 min).The adsorption process of ZIF-8/PP-g-MAH is consistent with that of the Langmuir isotherm and pseudo-second-order dynamic model.ZIF-8/PP-g-MAH also exhibits good selectivity for uranium in simulated seawater.The high adsorption performance of ZIF-8/PP-g-MAH is attributed to its membrane structure,which improves the utilization of coordination sites,including Zn-OH,C-N,and C=N.This study provides an efficient adsorption material for rapid uranium extraction,thus promoting the development of uranium extraction technologies. 展开更多
关键词 ZIF-8 Membrane URANIUM ADSORPTION
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Tuning strategies and structure effects of electrocatalysts for carbon dioxide reduction reaction 被引量:3
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作者 Cong Liu Xuanhao Mei +3 位作者 Ce Han Xue Gong Ping Song Weilin Xu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1618-1633,共16页
Carbon dioxide emissions have increased due to the consumption of fossil fuels,making the neutralization and utilization of CO_(2) a pressing issue.As a clean and efficient energy conversion process,electrocatalytic r... Carbon dioxide emissions have increased due to the consumption of fossil fuels,making the neutralization and utilization of CO_(2) a pressing issue.As a clean and efficient energy conversion process,electrocatalytic reduction can reduce carbon dioxide into a series of alcohols and acidic organic molecules,which can effectively realize the utilization and transformation of carbon dioxide.This review focuses on the tuning strategies and structure effects of catalysts for the electrocatalytic CO_(2) reduction reaction(CO_(2)RR).The tuning strategies for the active sites of catalysts have been reviewed from intrinsic and external perspectives.The structure effects for the CO_(2)RR catalysts have also been discussed,such as tandem catalysis,synergistic effects and confinement catalysis.We expect that this review about tuning strategies and structure effects can provide guidance for designing highly efficient CO_(2)RR electrocatalysts. 展开更多
关键词 CO_(2)RR Tuning strategies Active sites regulation Structure effect Tandem catalysis Synergistic effect
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Intercalation of multiply solvated hexafluorophospate anion into graphite electrode from mixtures of methyl acetate,ethyl methyl and ethylene carbonates 被引量:2
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作者 Lei Zhang Hongyu Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期233-236,共4页
Graphite is a universal host material for ion intercalation. Li+-graphite intercalation compounds (GICs) have been successfully utilized as the anode material in commercial lithium-ion batteries.Similarly, anion-graph... Graphite is a universal host material for ion intercalation. Li+-graphite intercalation compounds (GICs) have been successfully utilized as the anode material in commercial lithium-ion batteries.Similarly, anion-graphite intercalation compounds (AGICs) have been coming into their own in dual-ion batteries [1]. It is imperative to deepen an understanding of anion storage mechanisms in graphite electrode. 展开更多
关键词 Multiply solvated anions Anion-graphite intercalation compounds Methyl acetate Ethylene carbonate Ethyl methyl carbonate
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Design strategy and comprehensive performance assessment towards Zn anode for alkaline rechargeable batteries
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作者 Di Yang Jinsheng Li +2 位作者 Changpeng Liu Wei Xing Jianbing Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期122-138,I0004,共18页
Alkaline Zn-based primary batteries have been commercialized in the past decades.However,their success has not been extended to secondary batteries due to the poor cycle reversibility of Zn anodes.Although some resear... Alkaline Zn-based primary batteries have been commercialized in the past decades.However,their success has not been extended to secondary batteries due to the poor cycle reversibility of Zn anodes.Although some research has been conducted on alkaline Zn anodes,their performance is still far from commercial requirements.A variety of degradation mechanisms,including passivation,dendrites,morphological changes,and hydrogen precipitation,are claimed responsible for the failure of alkaline Zn metal anodes.What’s worse,these constraints always interact with each other,which leads to a single strategy being unable to suppress all the issues.Therefore,a comprehensive evaluation of the positive and negative effects of various strategies on performance is important to promote the commercialization of alkaline Zn batteries.Herein,the recent progress and performance of improvement strategies for Zn anode in alkaline conditions are reviewed systematically.First,the principles and challenges of alkaline Zn anodes are briefly analyzed.Then,various design strategies for alkaline Zn anodes from the perspectives of ion and electron regulation are highlighted.Last,through a comprehensive summary of various performance parameters,the advantages and disadvantages of different strategies are compared and evaluated.On the basis of this assessment,we aim to provide more insights into the anode design of high-performance alkaline rechargeable Zn batteries. 展开更多
关键词 Alkaline aqueous batteries Zinc anode Regulation strategies Performance assessment
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The decisive role of adsorbed OH^(*)in low‐potential CO electro‐oxidation on single‐atom catalytic sites
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作者 Yang Li Xian Wang +7 位作者 Ying Wang Zhaoping Shi Yuqi Yang Tuo Zhao Zheng Jiang Changpeng Liu Wei Xing Junjie Ge 《Carbon Energy》 SCIE EI CAS CSCD 2023年第9期63-73,共11页
CO impurity-induced catalyst deactivation has long been one of the biggest challenges in proton-exchange membrane fuel cells,with the poisoning phenomenon mainly attributed to the overly strong adsorption on the catal... CO impurity-induced catalyst deactivation has long been one of the biggest challenges in proton-exchange membrane fuel cells,with the poisoning phenomenon mainly attributed to the overly strong adsorption on the catalytic site.Here,we present a mechanistic study that overturns this understanding by using Rh-based single-atom catalysis centers as model catalysts.We precisely modulated the chelation structure of the Rh catalyst by coordinating Rh with C or N atoms,and probed the reaction mechanism by surface-enhanced Raman spectroscopy.Direct spectroscopic evidence for intermediates indicates that the reactivity of adsorbed OH^(*),rather than the adsorption strength of CO^(*),dictates the CO electrocatalytic oxidation behavior.The RhN_(4)sites,which adsorb the OH^(*)intermediate more weakly than RhC4 sites,showed prominent CO oxidation activity that not only far exceeded the traditional Pt/C but also the RhC4 sites with similar CO adsorption strength.From this study,it is clear that a paradigm shift in future research should be considered to rationally design high-performance CO electro-oxidation reaction catalysts by sufficiently considering the water-related reaction intermediate during catalysis. 展开更多
关键词 adsorbed CO^(*)and OH^(*) carbon‐based Rh single‐atom catalysts CO electro‐oxidation reaction electron interaction MNx moiety
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Next-generation vaccines for substance use disorders 被引量:1
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作者 Kaixuan Wang Hongshuang Wang Xiaohui Wang 《Zoological Research》 SCIE CSCD 2024年第3期707-708,共2页
Substance use disorders(SUDs)impact an estimated 300 million people worldwide,significantly impairing both health and social functioning.These disorders are marked by an inability to regulate substance use,despite the... Substance use disorders(SUDs)impact an estimated 300 million people worldwide,significantly impairing both health and social functioning.These disorders are marked by an inability to regulate substance use,despite the harmful consequences.Addiction affects various neurotransmitter systems,including dopamine,serotonin,γ-aminobutyric acid(GABA),and glutamate,each of which plays a role in the reward,stress,and self-control pathways of the brain(Koob&Volkow,2016).While significant advances have been made in neuroscience,our understanding of how these neurotransmitter systems interact and contribute to addiction is still evolving.This knowledge gap represents a significant challenge in the formulation of effective treatments for SUDs.At present,the US Food and Drug Administration(FDA)has approved pharmacological treatments for alcohol,nicotine,and opioid use disorders(Vasiliu,2022);however,no such treatments have been authorized for SUDs in general,or specifically for stimulant use disorders,such as cocaine and methamphetamine addiction.Notably,the FDA has not approved any new drugs for SUD treatment in the past 40 years. 展开更多
关键词 DISORDERS TREATMENT consequences
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Microglia in drug addiction:A perspective from neuroimmunopharmacology 被引量:1
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作者 Cong Lin Xiaohui Wang 《Zoological Research》 SCIE CSCD 2024年第3期704-706,共3页
Drug addiction refers to a state of dependence that arises from habitual drug intake and can result in specific withdrawal symptoms upon cessation.The most commonly abused substances include psychostimulants,cannabino... Drug addiction refers to a state of dependence that arises from habitual drug intake and can result in specific withdrawal symptoms upon cessation.The most commonly abused substances include psychostimulants,cannabinoids,and opioids.When drugs are consumed,they stimulate the release of dopamine,a neurotransmitter crucial for the pleasure and reward centers of the brain.With repeated drug use,the brain undergoes various changes,leading to tolerance,dependence,and addiction(Lüscher et al.,2020).The mechanisms involved in drug addiction are highly complex and involve diverse cell types within the brain. 展开更多
关键词 ADDICTION DRUGS INTAKE
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Vacancy engineering induced reaction kinetics enhancement of cobalt metaphosphate for pH-universal hydrogen evolution
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作者 Yuting Chen Tian Meng +5 位作者 Zhicai Xing Yueying Yan Yang Yang Bohan Yao Dewen Wang Xiurong Yang 《Nano Research》 SCIE EI CSCD 2024年第5期3879-3887,共9页
Developing efficient pH-universal hydrogen evolution reaction(HER)catalysts is critical in the field of water electrolysis,however,which is severely hampered by the sluggish kinetics in alkaline media.Herein,a rutheni... Developing efficient pH-universal hydrogen evolution reaction(HER)catalysts is critical in the field of water electrolysis,however,which is severely hampered by the sluggish kinetics in alkaline media.Herein,a ruthenium(Ru)incorporation induced vacancy engineering strategy is firstly proposed to precisely construct oxygen vacancy(V_(O))-riched cobalt-ruthenium metaphosphate(CRPO)for high-efficiency pH-universal HER.The V_(O) modifies the electronic structure,improves the superficial hydrophilic and gas spillover capacity,it also reduces the coordination number of Ru atoms and regulates the coordination environment.Theoretical calculations indicate that Ru tends to adsorb H_(2)O and H^(*),whereas V_(O) tends to adsorb OH^(-),which greatly promotes the H_(2)O adsorption and the dissociation of HO-H bond.Ultimately,CRPO-2 exhibits remarkable HER performance,the mass activity is about 18.34,21.73,and 38.07 times higher than that of Pt/C in acidic,neutral,and alkaline media,respectively,at the same time maintain excellent stability.Our findings may pave a new avenue for the rational design of electrocatalysts toward pH-universal water electrolysis. 展开更多
关键词 cobalt metaphosphate pH-universal hydrogen evolution reaction(HER) vacancy engineering low-coordination atoms oxygen vacancy
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Tuning microstructures of Mg-Ce-Ni hydrogen storage alloys via Cu and carbon nanotube additions
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作者 Linlin Zhang Liang Xiong +7 位作者 Bingyang Gao Qingyun Shi Ying Wang Zhiya Han Zhenhua Zhang Chunli Wang Limin Wang Yong Cheng 《Nano Research》 SCIE EI CSCD 2024年第8期7203-7211,共9页
Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics an... Mg-based alloys are regarded as highly promising materials for hydrogen storage.Despite significant improvements of the properties for Mg-based alloys,challenges such as slow hydrogen absorption/desorption kinetics and high thermodynamic stability continue to limit their practical application.In this study,to assess hydrogen storage alloys with enhanced properties,incorporating both internal microstructure modulation through the preparation of amorphous/nanocrystalline structures and surface property enhancement with the addition of Cu and carbon nanotubes(CNTs),the kinetic properties of activation and hydrogenation,thermodynamic properties,and dehydrogenation kinetics are tested.The results reveal a complementary interaction between the added Cu and CNTs,contributing to the superior hydrogen storage performance observed in sample 7A-2Cu-1CNTs with an amorphous/nanocrystalline structure compared to the other experimental samples.Additionally,the samples are fully activated after the initial hydrogen absorption and desorption cycle,demonstrating outstanding hydrogenation kinetics under both high and low temperature experimental conditions.Particularly noteworthy is that the hydrogen absorption exceeds 1.8 wt.% within one hour at 333 K.Furthermore,the activation energy for dehydrogenation is decreased to 64.71 kJ·mol^(–1).This research may offer novel insights for the design of new-type Mg-based hydrogen storage alloys,which possess milder conditions for hydrogen absorption and desorption. 展开更多
关键词 Mg-Ni-Ce alloy hydrogen storage amorphous/nanocrystalline structure kinetics Cu and carbon nanotubes(CNTs)codoping
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Differentially-grown cobalt regulators cooperatively involved in the tandem catalysis for high-yield production of second amines
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作者 Jinhui Xu Xiao Wang +5 位作者 Ying Wang Fei Wang Lingling Zhang Wenjie Cui Shuyan Song Hongjie Zhang 《Nano Research》 SCIE EI CSCD 2024年第4期2444-2450,共7页
One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing se... One-pot tandem catalysis has been regarded as one of the most atomic economic ways to produce secondary amines,the important platform molecules for chemical synthesis and pharmaceutical manufacture,but it is facing serious issues in overall efficiency.New promotional effects are highly desired for boosting the activity and regulating the selectivity of conventional tandem catalysts.In this work,we report a high-performance tandem catalyst with maximized synergistic effect among each counterpart by preciously manipulating the spatial structure,which involves the active CeO_(2)/Pt component as kernel,the densely-coated N-doped C(NC)layer as selectivity controller,and the differentially-grown Co species as catalytic performance regulators.Through comprehensive investigations,the unique growth mechanism and the promotion effect of Co regulators are clarified.Specifically,the surface-landed Co clusters(Cocs)are crucial to selectivity by altering the adsorption configuration of benzylideneaniline intermediates.Meanwhile,the inner Co particles(Cops)are essential for activity by denoting their electrons to neighboring Ptps.Benefiting from the unique promotion effect,a remarkably-improved catalytic efficiency(100%nitrobenzene conversion with 94%N-benzylaniline selectivity)is achieved at a relatively low temperature of 80℃,which is much better than that of CeO_(2)/Pt(100%nitrobenzene conversion with 12%N-benzylaniline selectivity)and CeO_(2)/Pt/NC(35%nitrobenzene conversion with 94%benzylideneaniline selectivity). 展开更多
关键词 tandem catalysis CeO_(2) hierarchical structure heterogeneous catalyst dual-site materials
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Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides
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作者 Feng Ren Zhuang-Zhuang Liang +2 位作者 Ming-Xin Niu Chen-Yang Hu Xuan Pang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第2期168-175,I0006,共9页
Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segmen... Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic systems.The new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability. 展开更多
关键词 Polyester POLYETHER Alternative copolymer Ring-opening polymerization
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Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts
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作者 Qi-Yuan Wang Li-Peng Sang +5 位作者 Zhen Zhang Yang Jiang Hui Tian Xia Zhao Xiang Guo Shi-Hui Li 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第2期223-229,I0008,共8页
Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-san... Coordination polymerization of renewable β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandwich benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show trans-1,2-regioselectivities and high activities, of which 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene with isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins with enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity. 展开更多
关键词 Biobased monomer TERPENES OCIMENE RARE-EARTHS Polymerization Regio/stereoselectivity Elastomer
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Atomic-level coupled RuO_(2)/BaRuO_(3) heterostructure for efficient alkaline hydrogen evolution reaction
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作者 Yueying Yan Tian Meng +4 位作者 Yuting Chen Yang Yang Dewen Wang Zhicai Xing Xiurong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期356-362,I0009,共8页
The slow water dissociation is the rate-determining step that slows down the reaction rate in alkaline hydrogen evolution reaction(HER).Optimizing the surface electronic structure of the catalyst to lower the energy b... The slow water dissociation is the rate-determining step that slows down the reaction rate in alkaline hydrogen evolution reaction(HER).Optimizing the surface electronic structure of the catalyst to lower the energy barrier of water dissociation and regulating the binding strength of adsorption intermediates are crucial strategy for boosting the catalytic performance of HER.In this study,RuO_(2)/BaRuO_(3)(RBRO)heterostructures with abundant oxygen vacancies and lattice distortion were in-situ constructed under a low temperature via the thermal decomposition of gel-precursor.The RBRO heterostructures obtained at 550℃ exhibited the highest HER activity in 1 M KOH,showing an ultra-low overpotential of 16 mV at 10 mA cm^(-2)and a Tafel slope of 33.37 m V dec^(-1).Additionally,the material demonstrated remarkable durability,with only 25 mV of degradation in overpotential after 200 h of stability testing at 10 mA cm^(-2).Density functional theory calculations revealed that the redistribution of charges at the heterojunction interface can optimize the binding energies of H*and OH*and effectively lower the energy barrier of water dissociation.This research offers novel perspectives on surpassing the water dissociation threshold of alkaline HER catalysts by means of a systematic design of heterogeneous interfaces. 展开更多
关键词 HETEROSTRUCTURE Hydrogen evolution reaction Interfacial electron transfer Oxygen vacancies
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Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates
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作者 Hao-Tian Zhang Ming-Xin Niu +2 位作者 Qi Zhang Chen-Yang Hu Xuan Pang 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第3期292-298,I0005,共8页
Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits... Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics. 展开更多
关键词 Polyisothioureas Alternative copolymer AZIRIDINES Isothiocayanates
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Heterostructured Pt-Ni_(3)Mo_(3)N formed via ammonia-containing polyoxometalates for highly efficient electrocatalytic hydrogen evolution in acid medium
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作者 Bianqing Ren Xue Gong +5 位作者 Jing Cao Dezheng Zhang Zizhun Wang Ping Song Ce Han Weilin Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期698-704,共7页
Constructing heterostructured nanohybrid is considered as a prominent route to fabricate alternative electrocatalysts to commercial Pt/C for hydrogen evolution reaction(HER).In this work,(NH_(4))_(4)[NiH_(6)Mo_(6)O_(4... Constructing heterostructured nanohybrid is considered as a prominent route to fabricate alternative electrocatalysts to commercial Pt/C for hydrogen evolution reaction(HER).In this work,(NH_(4))_(4)[NiH_(6)Mo_(6)O_(4)]·5H_(2)O polyoxometalates(NiMo_(6))are adopted as the cluster precursors for simple fabrication of heterostructured Pt-Ni_(3)Mo_(3)N nanohybrids supported by carbon black(Pt-Ni_(3)Mo_(3)N/C)without using additional N sources.The improved porosity and enhanced electronic interaction of Pt-Ni_(3)Mo_(3)N/C should be attributed to the integration of Pt with NiMo_(6),which favors the mass transport,promotes the formation of exposed catalytic sites,and benefits the regulation of intrinsic activity.Thus,the as-obtained Pt-Ni_(3)Mo_(3)N/C exhibits impressive and durable HER performance as indicated by the low overpotential of 13.7 mV at the current density of 10 mA cm^(-2) and the stable overpotential during continuous working at 100 mA cm^(-2) for 100 h.This work provides significant insights for the synthesis of new highly active heterostructured electrocatalysts for renewable energy devices. 展开更多
关键词 POLYOXOMETALATES Cluster precursors Heterostructured nanohybrids Hydrogen evolution reaction ELECTROCATALYSIS
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Molecule aging induced by electron attacking
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作者 Ping Song Yining Dong +5 位作者 Xue Gong Mingbo Ruan Baoxin Ni Xuanhao Mei Kun Jiang Weilin Xu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期519-525,I0013,共8页
Here we propose a new concept of"molecule aging":with some special treatment,a molecule could be"aged"by losing some unknown tiny particles or pieces from atoms in the molecule,Such"aging"... Here we propose a new concept of"molecule aging":with some special treatment,a molecule could be"aged"by losing some unknown tiny particles or pieces from atoms in the molecule,Such"aging"or loss of unknown tiny particles does not change apparently its molecular structure or chemical composition,but some physicochemical properties could be changed irreversibly.We further confirm such"molecule aging"via a long-term electron attacking to age water(H_(2)O)molecules.The IR spectra show no structural difference between the fresh water and the aged one,while the NMR spectra show that the electron attacking can decrease the size of water clusters.Such facts indicate that the electron attacking indeed can"affect"the structure of water molecule slightly but without damaging to its basic molecule frame.Further exploration reveals that the hydrogen evolution reaction(HER)activity of the aged water molecule is lower than the fresh water on the same Pt/C electrocatalyst.The density functional theory calculations indicate that the shortened O-H bond in H_(2)O indeed can present lower HER activity,so the observed size decrease of water clusters from NMR probably could be attributed to the shortening of O-H bond in water molecules.Such results indicate significantly that the molecule aging can produce materials with new functions for new possible applications. 展开更多
关键词 Aging of molecules Electron attacking Full width at half maxima Hydrogen evolution reaction
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Structural Properties of Ions and Polyelectrolytes in Aqueous Solutions under External Electric Fields:The Sign Effect
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作者 Cheng-Jiang Lin Jun-Jun Wang +6 位作者 Yuan Jiang Shu-Li Chen Hong-Fei Li Wen-Han Zhao Qing-Rong Huang Chang-Ru Rong Xiao-Zheng Duan 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第9期1341-1352,I0007,共13页
We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric fields.By focusing on the multi-body interactions between ionic co... We utilize molecular dynamics simulations to investigate the microstructures of ions and polyelectrolytes in aqueous solutions under external electric fields.By focusing on the multi-body interactions between ionic components and H_(2)O molecules,as well as their responses to the external electric fields,we clarify several nontrivial molecular features of the ionic and polyelectrolyte solutions,such as the solvations of cations and anions,clustering of the ions,and dispersions/aggregations of polyelectrolyte chains,as well as the corresponding responses of H_(2)O molecules in these contexts.Our simulations illustrate the variations in structures of ionic solutions caused by reversing the charge sign of the ions,and elucidate the disparity in structures between anionic and cationic polyelectrolyte solutions in the presence of the external electric fields.This work clarifies the mechanism for the alternations in complex multi-body interactions in aqueous solutions caused by the application electric field,which can contribute to the fundamental understanding of the physical and chemical natures of ion-containing and charged polymeric systems. 展开更多
关键词 POLYELECTROLYTE IONS Aqueous solutions External electric fields Asymmetric dipole
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Atomically dispersed Fe sites on hierarchically porous carbon nanoplates for oxygen reduction reaction
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作者 Ruixue Zheng Qinglei Meng +9 位作者 Hao Zhang Teng Li Di Yang Li Zhang Xiaolong Jia Changpeng Liu Jianbing Zhu Xiaozheng Duan Meiling Xiao Wei Xing 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期7-15,I0002,共10页
Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air bat... Developing cost-effective,robust and stable non-precious metal catalysts for oxygen reduction reaction(ORR) is of paramount importance for electrochemical energy conversion devices such as fuel cells and metal-air batteries.Although Fe-N-C single atom catalysts(SACs) have been hailed as the most promising candidate due to the optimal binding strength of ORR intermediates on the Fe-N_(4) sites,they suffer from serious mass transport limitations as microporous templates/substrates,i.e.,zeolitic imidazolate frameworks(ZIFs),are usually employed to host the active sites.Motivated by this challenge,we herein develop a hydrogen-bonded organic framework(HOF)-assisted pyrolysis strategy to construct hierarchical micro/mesoporous carbon nanoplates for the deposition of atomically dispersed Fe-N_(4) sites.Such a design is accomplished by employing HOF nanoplates assembled from 2-aminoterephthalic acid(NH_(2)-BDC) and p-phenylenediamine(PDA) as both soft templates and C,N precursors.Benefitting from the structural merits inherited from HOF templates,the optimized catalyst(denoted as Fe-N-C SAC-950) displays outstanding ORR activity with a high half-wave potential of 0.895 V(vs.reversible hydrogen electrode(RHE)) and a small overpotential of 356 mV at 10 mA cm^(-2) for the oxygen evolution reaction(OER).More excitingly,its application potential is further verified by delivering superb rechargeability and cycling stability with a nearly unfading charge-discharge gap of 0.72 V after 160 h.Molecular dynamics(MD) simulations reveal that micro/mesoporous structure is conducive to the rapid mass transfer of O_(2),thus enhancing the ORR performance.In situ Raman results further indicate that the conversion of O_(2) to~*O_(2)-the rate-determining step(RDS) for Fe-N-C SAC-950.This work will provide a versatile strategy to construct single atom catalysts with desirable catalytic properties. 展开更多
关键词 Fe single atom catalysts Oxygen reduction reaction Mesoporous structure Active sites Zinc-air battery
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Dimethylsulfoniopropionate (DMSP) Increases Longevity and Mitochondrial Function in Caenorhabditis elegans: Implications for the Role of the Global Sulfur Cycle in Terrestrial Ecosystems
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作者 Hongyuan Li Peng Ji +6 位作者 Yue Cao Zhitao Cui Jingwei Gao Hongshuang Wang Cong Lin Yibo Wang Xiaohui Wang 《Environment & Health》 2024年第8期572-585,共14页
Dimethylsulfoniopropionate(DMSP)is a compound synthesized by marine phytoplankton that contributes to the oceanic sulfur cycle.Interestingly,DMSP has also been found in algal species and several terrestrial plants,for... Dimethylsulfoniopropionate(DMSP)is a compound synthesized by marine phytoplankton that contributes to the oceanic sulfur cycle.Interestingly,DMSP has also been found in algal species and several terrestrial plants,forming part of the global sulfur cycle.However,compared to its role in the marine environment,the impact of DMSP on terrestrial ecosystems remains relatively unexplored.In this study,DMSP was shown to promote longevity and prevent age-associated functional decline in Caenorhabditis elegans(C.elegans),a soil-dwelling organism.DMSP decreased mitochondrial content and improved mitochondrial function in C.elegans at the old stage,which was via enhancing autophagy flux.It was demonstrated that DMSP significantly increased the expression of autophagy and mitophagy genes during aging.Furthermore,DMSP protected against Parkinson’s disease(PD)induced byα-synuclein(α-syn)aggregation via autophagy.Mechanistic studies showed that DMSP directly activated nuclear translocation of the Skinhead-1(SKN-1)transcription factor from the cytoplasm.Moreover,SKN-1 was involved in DMSP-induced autophagy and played a key role in lifespan extension andα-syn clearance in C.elegans.In conclusion,DMSP delays physiological aspects of aging in C.elegans,providing insights into the interplay between the global sulfur cycle and terrestrial organisms. 展开更多
关键词 DMSP C.elegans terrestrial ecosystem aging autophagy
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