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Hierarchical porous hard carbon enables integral solid electrolyte interphase as robust anode for sodium-ion batteries 被引量:16
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作者 Xu-Kun Wang Juan Shi +5 位作者 Li-Wei Mi Yun-Pu Zhai Ji-Yu Zhang Xiang-Ming Feng Zi-Jie Wu Wei-Hua Chen 《Rare Metals》 SCIE EI CAS CSCD 2020年第9期1053-1062,共10页
Hard carbon is the most promising anode for sodium-ion battery applications due to the wide availability and low work voltage.However,it often delivers worse electrochemical performance in ester-based electrolytes.Her... Hard carbon is the most promising anode for sodium-ion battery applications due to the wide availability and low work voltage.However,it often delivers worse electrochemical performance in ester-based electrolytes.Herein,a hierarchically porous loose sponge-like hard carbon with a highly disordered phase,prepared from the biomass of platanus bark,exhibits superior rate performance with a capacity of 165 mAh·g-1 at a high current of1 A·g-1,and high retention of 71.5%after 2000 cycles in an ester-based electrolyte.The effect of the hierarchically porous loose sponge-like structure on the formation dynamics of solid electrolyte interphase(SEI),and related properties,was studied via cyclic voltammetry(CV),galvanostatic intermittent titration technique(GITT),X-ray photoelectron spectroscope(XPS),Fourier transform infrared spectroscopy(FTIR)and electrochemical impedance spectroscopy(EIS)analysis.These results reveal that the hierarchically porous structure can construct continued connecting channels and accelerate the electrolyte transport,which is beneficial to the reaction kinetics of SEI.Moreover,the mesoporous structure is conducive to good contact between electrolyte and materials and shortens the Na+diffusion path,which in turn facilitates the charge transfer kinetics in the material. 展开更多
关键词 Sodium-ion battery Hard carbon hierarchically porous structure SEI Ester-based electrolyte
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空气过滤用静电纺聚苯乙烯/碳纳米管复合纤维膜的制备 被引量:11
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作者 汪策 李雄 +2 位作者 程诚 邓莉 王雪芬 《材料科学与工程学报》 CAS CSCD 北大核心 2016年第6期960-966,共7页
采用静电纺丝技术制备聚苯乙烯(PS)超细纤维、PS/多壁碳纳米管(MWCNTs)复合纳米纤维,并对其纤维形态结构、直径大小及空气过滤性能进行了表征。通过PS纺丝溶液浓度变化调控制备纯PS纤维多孔膜,并通过在PS纺丝液中添加不同含量MWCNT... 采用静电纺丝技术制备聚苯乙烯(PS)超细纤维、PS/多壁碳纳米管(MWCNTs)复合纳米纤维,并对其纤维形态结构、直径大小及空气过滤性能进行了表征。通过PS纺丝溶液浓度变化调控制备纯PS纤维多孔膜,并通过在PS纺丝液中添加不同含量MWCNTs调控纤维形态结构。SEM分析结果表明PS/MWCNTs复合纤维表面形成"褶皱"型和"山峰"型纳米级突起,复合纤维表面的粗糙度明显增加,且纤维直径明显减小。空气过滤性能测试结果发现这种多级结构使复合膜的过滤效率相比光滑的纯PS纳米纤维膜大幅提高,过滤性能得到明显改善。在85L/min气流速度下,PS/MWCNTs复合膜过滤效率高达99.95%,空气阻力为374.6Pa。选择尺寸较粗的微米级PS纤维(~2μm)和相对较细的纳米级PS/MWCNTs复合纤维(~800nm)进行混纺,调节复合膜堆积密度可使得混纺膜空气阻力降低到235.4Pa,仍能保持高的过滤效率(99.68%)。 展开更多
关键词 聚苯乙烯 碳纳米管 多级结构 静电纺丝 空气过滤
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多级孔沸石的孔结构调控合成及其催化应用研究进展 被引量:8
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作者 陈航榕 周晓霞 施剑林 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2018年第2期113-127,共15页
沸石由于特殊的离子交换性,丰富的酸性位以及较高的水热稳定性,被广泛地应用于工业催化和分离吸附等领域。但是由于其较小的微孔尺寸(<1.5 nm),在一些大分子参与的催化反应中受到极大的限制。多级孔沸石在保留传统沸石晶化骨架、酸... 沸石由于特殊的离子交换性,丰富的酸性位以及较高的水热稳定性,被广泛地应用于工业催化和分离吸附等领域。但是由于其较小的微孔尺寸(<1.5 nm),在一些大分子参与的催化反应中受到极大的限制。多级孔沸石在保留传统沸石晶化骨架、酸性位以及高水热稳定性的同时引入了多级孔结构,可极大改善分子的扩散和传质,减少积碳,延长催化剂的使用寿命,使其在催化领域获得更为广泛的应用。本文系统综述了多级孔沸石在孔结构调控方面的研究进展,着重介绍了无序介孔/大孔结构的多级孔沸石、有序介孔结构的多级孔沸石、取向排列的双介孔结构多级孔沸石、空心结构的多级孔沸石、集大孔–介孔–微孔为一体的多级孔沸石等的合成策略与机理以及结构表征。概述了多级孔沸石在催化领域中的应用进展;通过与传统沸石和无定型介孔材料的对比,这种新型的多级孔沸石展现出独特的优势。最后,对未来多级孔沸石的发展与应用潜力进行了展望。 展开更多
关键词 多级孔 沸石 结构调控 大孔/介孔/微孔 催化应用 综述
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Recent advances in the synthesis of nanoscale hierarchically porous metal–organic frameworks 被引量:7
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作者 Chongxiong Duan Kuan Liang +8 位作者 Zena Zhang Jingjing Li Ting Chen Daofei Lv Libo Li Le Kang Kai Wang Han Hu Hongxia Xi 《Nano Materials Science》 EI CAS CSCD 2022年第4期351-365,共15页
Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous st... Nanoscale hierarchically porous metal–organic frameworks(NHP-MOFs)have received unprecedented attention in many fields owing to their integration of the strengths of nanoscale size(<1μm)and hierarchical porous structure(micro-,meso-and/or macro-pores)of MOFs.This review focuses on recent advances in the main synthetic strategies for NHP-MOFs based on different metal ions(e.g.,Cu,Fe,Co,Zn,Al,Zr,and Cr),including the template method,composite technology,post-synthetic modification,in situ growth and the grind method.In addition,the mechanisms of synthesis,regulation techniques and the advantages and disadvantages of various methods are discussed.Finally,the challenges and prospects of the commercialisation of promising NHP-MOFs are also presented.The purpose of this review is to provide a road map for future design and development of NHP-MOFs for practical application. 展开更多
关键词 Metal–organic frameworks NANOSCALE hierarchically porous structure Synthesis strategies
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Support Effects on Thiophene Hydrodesulfurization over Co-Mo-Ni/Al_2O_3 and Co-Mo-Ni/TiO_2-Al_2O_3 Catalysts 被引量:7
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作者 刘超 周志明 +2 位作者 黄永利 程振民 袁渭康 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2014年第4期383-391,共9页
A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonate... A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 &#176;C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g^-1, 0.78 mmol·g^-1, 2.18 mmol·g^-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively. 展开更多
关键词 HYDRODESULFURIZATION SUPPORT hierarchically macro-/mesoporous structure AL2O3 TiO2-Al2O3
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In-situ growth of Ni nanoparticle-encapsulated N-doped carbon nanotubes on carbon nanorods for efficient hydrogen evolution electrocatalysis 被引量:6
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作者 Xiaoxiao Yan Minyi Gu +3 位作者 Yao Wang Lin Xu Yawen Tang Renbing Wu 《Nano Research》 SCIE EI CAS CSCD 2020年第4期975-982,共8页
Searching for inexpensive,efficient and durable electrocatalysts with earth-abundant elements toward the hydrogen evolution reaction(HER)is of vital importance for the future sustainable hydrogen economy,yet still rem... Searching for inexpensive,efficient and durable electrocatalysts with earth-abundant elements toward the hydrogen evolution reaction(HER)is of vital importance for the future sustainable hydrogen economy,yet still remains a formidable challenge.Herein,a facile template-engaged strategy is demonstrated for the direct in-situ growth of Ni nanoparticles and N-doped carbon nanotubes on carbon nanorod substrates,forming a hierarchically branched architecture(abbreviated as Ni@N-C NT/NRs hereafter).The elaborate construction of such unique hierarchical structure with tightly encapsulated Ni nanoparticles and open configuration endows the as-fabricated Ni@N-C NT/NRs with abundant well-dispersed active sites,enlarged surface area,reduced resistances of charge transfer and mass diffusion,and reinforced mechanical robustness.As a consequence,the optimal Ni@N-C NT/NR catalyst demonstrates superior electrocatalytic activity with relatively low overpotential of 134 mV to deliver a current density of 10 mA·cm^-2 and excellent stability for HER in 0.1 M KOH,holding a great promise for practical scalable H2 production.More importantly,this work offers a reliable methodology for feasible fabrication of robust high-performance carbon-based hierarchical architectures for a variety of electrochemical applications. 展开更多
关键词 hydrogen evolution reaction nitrogen-doped carbon nanotubes Ni nanoparticles carbon nanorods hierarchically branched structure
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Atomic-level-designed copper atoms on hierarchically porous gold architectures for high-efficiency electrochemical CO reduction 被引量:6
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作者 Yang Zhao Xunlin Liu +6 位作者 Dechao Chen Zhixiao Liu Qingcheng Yang Xin Lin Ming Peng Pan Liu Yongwen Tan 《Science China Materials》 SCIE EI CAS CSCD 2021年第8期1900-1909,共10页
Electrochemical CO_(2) reduction is a promising technology for solving the CO_(2) emission problems and producing value-added products. Here, we report a hierarchically porous Cu1Au single-atom alloy(SAA) as an effici... Electrochemical CO_(2) reduction is a promising technology for solving the CO_(2) emission problems and producing value-added products. Here, we report a hierarchically porous Cu1Au single-atom alloy(SAA) as an efficient electrocatalyst for CO_(2) reduction. Benefiting from the hierarchically porous architectures with abundant vacancies as well as three-dimensional accessible active sites, the as-prepared nanoporous Cu1Au SAA catalyst shows remarkable CO_(2) reduction performance with nearly 100% CO Faraday efficiency in a wide potential range(-0.4 to -0.9 V vs. reversible hydrogen electrode. The in-situ X-ray absorption spectroscopy studies and density functional theory calculations reveal that the Cu-Au interface sites serve as the intrinsic active centers,which can facilitate the activated adsorption of CO_(2) and stabilize the *COOH intermediate. 展开更多
关键词 hierarchically porous structure single-atom alloy electrochemical carbon dioxide reduction gold-copper alloy operando X-ray absorption spectroscopy
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ZSM-5分子筛在甲醇转化制烯烃领域应用的研究进展 被引量:5
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作者 冯琦瑶 邢爱华 +1 位作者 张新锋 姜继东 《工业催化》 CAS 2016年第1期15-23,共9页
综述了ZSM-5分子筛在甲醇制烯烃反应特别是在甲醇制丙烯反应中的应用。介绍在接近工业反应条件下甲醇在ZSM-5分子筛上生成烯烃的反应机理,在较高反应温度下高碳数烯烃裂解是导致轻烯烃形成的主要反应路径;分析ZSM-5分子筛酸性及粒径对... 综述了ZSM-5分子筛在甲醇制烯烃反应特别是在甲醇制丙烯反应中的应用。介绍在接近工业反应条件下甲醇在ZSM-5分子筛上生成烯烃的反应机理,在较高反应温度下高碳数烯烃裂解是导致轻烯烃形成的主要反应路径;分析ZSM-5分子筛酸性及粒径对产品选择性及催化剂寿命的影响,由于ZSM-5分子筛酸性较强,直接用于甲醇制烯烃反应时低碳烯烃的选择性不高,而粒径小的ZSM-5分子筛扩散性能好,因而丙烯选择性得到提高。重点介绍小晶粒ZSM-5分子筛的研究进展,指出目前ZSM-5分子筛的研究方向一是对其进行酸性改性,二是制备酸度适中、粒径合适和具有介孔的多级结构ZSM-5分子筛。 展开更多
关键词 催化剂工程 ZSM-5分子筛 甲醇制烯烃 酸性改性 多级结构
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Self-supporting and hierarchically porous Ni_(x)Fe-S/NiFe_(2)O_(4) heterostructure as a bifunctional electrocatalyst for fluctuating overall water splitting 被引量:5
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作者 Wenjing Yan Jintao Zhang +3 位作者 Aijing Lü Songle Lu Yiwei Zhong Mingyong Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第5期1120-1131,共12页
Stable non-noble metal bifunctional electrocatalysts are one of the challenges to the fluctuating overall water splitting driven by re-newable energy.Herein,a novel self-supporting hierarchically porous Ni_(x)Fe-S/NiF... Stable non-noble metal bifunctional electrocatalysts are one of the challenges to the fluctuating overall water splitting driven by re-newable energy.Herein,a novel self-supporting hierarchically porous Ni_(x)Fe-S/NiFe_(2)O_(4) heterostructure as bifunctional electrocatalyst was constructed based on porous Ni-Fe electrodeposition on three-dimensional(3D)carbon fiber cloth,in situ oxidation,and chemical sulfuration.Results showed that the Ni_(x)Fe-S/NiFe_(2)O_(4) heterostructure with a large specific surface area exhibits good bifunctional activity and stability for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)because of the abundance of active sites,synergistic effect of the heterostructure,superhydrophilic surface,and stable,self-supporting structure.The results further confirmed that the Ni_(x)Fe-S phase in the heterostructure is transformed into metal oxides/hydroxides and Ni_(3)S_(2) during OER.Compared with the commercial 20wt%Pt/C||IrO_(2)-Ta_(2)O_(5) electrolyzer,the self-supporting Ni1/5Fe-S/NiFe_(2)O_(4)||Ni1/2Fe-S/NiFe_(2)O_(4) electrolyzer exhibits better stability and lower cell voltage in the fluctu-ating current density range of 10-500 mA/cm^(2).Particularly,the cell voltage of Ni1/5Fe-S/NiFe_(2)O_(4)||Ni1/2Fe-S/NiFe_(2)O_(4) is only approximately 3.91 V at an industrial current density of 500 mA/cm^(2),which is lower than that of the 20wt%Pt/C||IrO_(2)-Ta_(2)O_(5) electrolyzer(i.e.,approximately 4.79 V).This work provides a promising strategy to develop excellent bifunctional electrocatalysts for fluctuating overall water splitting. 展开更多
关键词 SELF-SUPPORTING hierarchically porous structure HETEROstructure bifunctional catalyst overall water splitting
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Rational design of hierarchically porous Fe-N-doped carbon as efficient electrocatalyst for oxygen reduction reaction and Zn-air batteries 被引量:5
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作者 Zihan Meng Neng Chen +4 位作者 Shichang Cai Jiawei Wu Rui Wang Tian Tian Haolin Tang 《Nano Research》 SCIE EI CSCD 2021年第12期4768-4775,共8页
The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/el... The rational design and construction of hierarchically porous nanostructure for oxygen reduction reaction (ORR) electrocatalysts is crucial to facilitate the exposure of accessible active sites and promote the mass/electron transfer under the gas-solid-liquid triple-phase condition. Herein, an ingenious method through the pyrolysis of creative polyvinylimidazole coordination with Zn/Fe salt precursors is developed to fabricate hierarchically porous Fe-N-doped carbon framework as efficient ORR electrocatalyst. The volatilization of Zn species combined with the nanoscale Kirkendall effect of Fe dopants during the pyrolysis build the hierarchical micro-, meso-, and macroporous nanostructure with a high specific surface area (1,586 m^(2)·g^(−1)), which provide sufficient exposed active sites and multiscale mass/charge transport channels. The optimized electrocatalyst exhibits superior ORR activity and robust stability in both alkaline and acidic electrolytes. The Zn-air battery fabricated by such attractive electrocatalyst as air cathode displays a higher peak power density than that of Pt/C-based Zn-air battery, suggesting the great potential of this electrocatalyst for Zn-air batteries. 展开更多
关键词 hierarchically porous structure Fe-N-doped carbon electrocatalysts oxygen reduction reaction Zn-air batteries
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Hierarchically porous Cu current collector with lithiophilic CuxO interphase towards high-performance lithium metal batteries 被引量:5
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作者 Yaya Wang Zexu Zhao +4 位作者 Wei Zeng Xingbo Liu Lei Wang Jian Zhu Bingan Lu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第7期292-299,共8页
Lithium metal is one of the most promising anode materials for next-generation electrochemical energy storage due to low electrochemical potential and high specific capacity.However,large volume change and uncontrolla... Lithium metal is one of the most promising anode materials for next-generation electrochemical energy storage due to low electrochemical potential and high specific capacity.However,large volume change and uncontrollable formation of lithium dendrite during cycling severely hinder the practical application of rechargeable Li metal batteries.Herein,we report a hierarchically porous Cu covered with lithiophilic CuxO(HPCu-CuxO) via femtosecond laser strategy in about 2 min as current collector for highperformance Li metal batteries.With precisely tunable pore volume and depth as well as lithiophilic CuxO interphase,the HPCu-CuxO not only guides homogeneous Li nucleation,resulting in a smooth and dendrite-free lithium surface,but also provides space to alleviate the volume expansion of Li metal anode,achieving excellent structure stability.Consequently,highly stable Coulombic efficiency and ultralow overpotential of 15 mV even up to 1000 h were achieved at the current density of 1 mA cm^(-2).Moreover,the resultant Li@HPCu-CuxO//LiFePO_(4) full battery delivered outstanding cycle stability and rate capability.These results offer a pathway toward high-energy-density and safe rechargeable Li metal batteries. 展开更多
关键词 Lithium metal batteries Femtosecond laser strategy hierarchically porous structure Lithiophilic CuxO interphase
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Hierarchically porous Co@N-doped carbon fiber assembled by MOF-derived hollow polyhedrons enables effective electronic/mass transport:An advanced 1D oxygen reduction catalyst for Zn-air battery 被引量:4
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作者 Yifei Zhang Quanfeng He +4 位作者 Zihao Chen Yuqing Chi Junwei Sun Ding Yuan Lixue Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第1期117-126,I0004,共11页
Developing advanced oxygen reduction reaction(ORR)electrocatalysts with rapid mass/electron transport as well as conducting relevant kinetics investigations is essential for energy technologies,but both still face ong... Developing advanced oxygen reduction reaction(ORR)electrocatalysts with rapid mass/electron transport as well as conducting relevant kinetics investigations is essential for energy technologies,but both still face ongoing challenges.Herein,a facile approach was reported for achieving the highly dispersed Co nanoparticles anchored hierarchically porous N-doped carbon fibers(Co@N-HPCFs),which were assembled by core-shell MOFs-derived hollow polyhedrons.Notably,the unique one-dimensional(1D)carbon fibers with hierarchical porosity can effectively improve the exposure of active sites and facilitate the electron transfer and mass transfer,resulting in the enhanced reaction kinetics.As a result,the ORR performance of the optimal Co@N-HPCF catalysts remarkably outperforms that of commercial Pt/C in alkaline solution,reaching a limited diffusion current density(J)of 5.85 m A cm^(-2)and a half-wave potential(E_(1/2))of 0.831 V.Particularly,the prepared Co@N-HPCF catalysts can be used as an excellent air-cathode for liquid/solid-state Zn-air batteries,exhibiting great potentiality in portable/wearable energy devices.Furthermore,the reaction kinetic during ORR process is deeply explored by finite element simulation,so as to intuitively grasp the kinetic control region,diffusion control region,and mixing control region of the ORR process,and accurately obtain the relevant kinetic parameters.This work offers an effective strategy and a reliable theoretical basis for the engineering of first-class ORR electrocatalysts with fast electronic/mass transport. 展开更多
关键词 Oxygen reduction catalyst Metal-organic frameworks Carbon nanofiber hierarchically porous structure Diffusion kinetics Zn-air battery
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Synthesis of ZSM-5 monoliths with hierarchical porosity through a steam-assisted crystallization method using sponges as scaffolds 被引量:5
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作者 Tiejing Hu Jian Liu +1 位作者 Changyan Cao Weiguo Song 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第5期872-878,共7页
Self‐supporting ZSM‐5crystals with hierarchical porosity were prepared through a steam‐assisted crystallization method using sponges as rigid scaffolds.The synthesized materials were characterized by X‐ray diffrac... Self‐supporting ZSM‐5crystals with hierarchical porosity were prepared through a steam‐assisted crystallization method using sponges as rigid scaffolds.The synthesized materials were characterized by X‐ray diffraction,nitrogen sorption,scanning electron microscopy,transmission electron microscopy,solid‐state nuclear magnetic resonance spectroscopy and ammonia temperature‐programmed desorption.The ZSM‐5monoliths exhibited high crystallinities,hierarchical porous structures and strong acidities.They showed superior catalytic performance in the liquid‐phase esterification reaction between benzyl alcohol and hexanoic acid. 展开更多
关键词 hierarchically porous structure ZEOLITE Steam‐assisted crystallization ACIDITY
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Hierarchically Macroporous Zeolite ZSM-5 Microspheres for Efficient Catalysis
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作者 ZHENG Mingdan CHEN Ya +5 位作者 LIU Zhan LYU Jiamin YE Bo SUN Ming-Hui CHEN Li-Hua SU Bao-Lian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2024年第4期704-711,共8页
Hollow zeolite microspheres have recently attracted much attention for their applications in catalysis,microreactors and biomedicine.Herein,we present hierarchically structured zeolite ZSM-5 microspheres with unique,a... Hollow zeolite microspheres have recently attracted much attention for their applications in catalysis,microreactors and biomedicine.Herein,we present hierarchically structured zeolite ZSM-5 microspheres with unique,abundant macropores that allow more efficient use for catalysis.The hierarchically macroporous zeolite ZSM-5 microspheres are synthesized under the assistance of water/oil emulsions and using polystyrene nanospheres as templates.The zeolite microsphere is assembled by uniform hollow zeolite nanospheres.Their large inner cavities and thin zeolite shells lead to smaller diffusion channel and higher improved accessibility to active sites,contributing to high catalytic performance in the catalytic conversion of benzyl alcohol in mesitylene.Such novel zeolite microspheres with impressive performance will be applied to numerous other industrial catalytic reactions. 展开更多
关键词 hierarchically porous structure Hollow structure MICROSPHERE Zeolite ZSM-5 ALKYLATION
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Ultra-stable and High-rate Lithium Ion Batteries Based on Metal-organic Framework-derived ln2O3 Nanocrystals/Hierarchically Porous Nitrogen-doped Carbon Anode 被引量:4
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作者 Hanjiao Xu Lei Wang +7 位作者 Jiang Zhong Tao Wang Jinhui Cao Yaya Wang Xiuqi Li Huilong Fei Jian Zhu Xidong Duan 《Energy & Environmental Materials》 2020年第2期177-185,共9页
Exploring electrode materials with attractive specific capacity and prominent cyclic durability is of the essence for promoting lithium ion batteries(LIBs).In2O3 has shown an extraordinary promise for LIBs with advant... Exploring electrode materials with attractive specific capacity and prominent cyclic durability is of the essence for promoting lithium ion batteries(LIBs).In2O3 has shown an extraordinary promise for LIBs with advantageous gravimetric capacity(theoretically 965 mA h g-1) and low working voltage.However,In2O3 still suffers from the inherent weaknesses of metal oxides in practical application,especially low conductivity and incorrigible volume expansion upon the cycling process.Here,we demonstrate the architecture of metal-organic framework(MOF)-derived In2O3 nanocrystals/hierarchically porous nitrogen-doped carbon composite(In2O3/HPNC) for ultra-stable LIBs anode.This hierarchically porous structure(micro/meso/macro-pores) with nitrogen doping not only ensures exceptional mechanical strength and accommodates the volume expansion of In2O3 nanocrystals,but also offers electrons and lithium ions efficient interpenetrating pathways to migrate rapidly during charge/discharge processes.Thus,In2O3/HPNC exhibits excellent cyclic stability with a high specific capacity of 623 mA h g-1 over2000 cycles at 1000 mA g-1,corresponding to an ultra-low specific capacity decay of 0.017% per cycle(the best among the ln203-based anode for LIBs),and outstanding rate performance,suggesting a critical step toward achieving long-life and high-rate LIBs in practical devices. 展开更多
关键词 hierarchically porous structure In203 nanocrystals metal-organic frameworks nitrogen-doping carbon ultra-stable lithium ion batteries
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Self-template synthesis of hierarchically structured Co3O4@NiO bifunctional electrodes for selective nitrate reduction and tetrahydroisoquinolines semidehydrogenation 被引量:3
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作者 Yuting Wang Cuibo Liu +1 位作者 Bin Zhang Yifu Yu 《Science China Materials》 SCIE EI CSCD 2020年第12期2530-2538,共9页
The rational design and synthesis of hierarchically hollow nanostructures with controlled spatial architecture and composition are significant in electrocatalysis owing to their abundant active sites and the expedited... The rational design and synthesis of hierarchically hollow nanostructures with controlled spatial architecture and composition are significant in electrocatalysis owing to their abundant active sites and the expedited electron/mass transfer.Electrocatalytic nitrate reduction to ammonia is of great interest from the points of environmental protection and energy saving.However,the development of this technology is hindered by the lack of efficient nitrate-toammonia electrocatalysts and the kinetically sluggish oxygen evolution reaction at the anode.Herein,a novel self-template conversion method was developed for the synthesis of Co3O4@Ni O hierarchical nanotubes(Co3O4@Ni O HNTs)with Ni O porous nanosheets assembled on Co3O4nanotubes.The as-obtained Co3O4@Ni O HNTs exhibited an outstanding performance for both the cathodic nitrate electroreduction to ammonia reaction and the anodic tetrahydroisoquinolines(THIQs)semi-dehydrogenation to dihydroisoquinolines(DHIQs).Importantly,a two-electrode system of Co3O4@Ni O HNTs||Co3O4@Ni O HNTs was constructed for the simultaneous synthesis of ammonia and DHIQs with high selectivity and robust stability. 展开更多
关键词 hierarchically hollow structure self-template cation exchange electrocatalysis bifunctional electrodes
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Atomically dispersed hierarchically ordered porous Fe-N-C single-atom nanozymes for dyes degradation 被引量:2
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作者 Shuangli Wu Weiwei Wu +3 位作者 Xinyang Zhu Minghua Li Jianguo Zhao Shaojun Dong 《Nano Research》 SCIE EI CSCD 2023年第8期10840-10847,共8页
The development of novel nanozymes for environmental contamination remediation is a worthwhile research direction.However,most of the reported nanozymes cannot degrade efficiently due to the limitation of the internal... The development of novel nanozymes for environmental contamination remediation is a worthwhile research direction.However,most of the reported nanozymes cannot degrade efficiently due to the limitation of the internal active sites not being able to come into direct contact with contaminants.Therefore,we reported Fe-N-C single-atom nanozymes(SAzymes)with atomically dispersed FeN4 active sites anchored on a three-dimensional hierarchically ordered microporous-mesoporous-macroporous nitrogen doped carbon matrix(3DOM Fe-N-C)for the degradation of a targeted environmental pollutant(rhodamine B(RhB)).The three-dimensional(3D)hierarchically ordered porous structure may accelerate mass transfer and improve the accessibility of active sites.This structure and high metal atom utilization endow Fe-N-C SAzyme with enhanced tri-enzyme-mimic activities,comprising oxidase-mimic,peroxidase-mimic,and catalase-mimic activities.Based on its excellent peroxidase-mimic activity,3DOM Fe-N-C can degrade RhB by hydroxyl radicals(·OH)generated in the presence of hydrogen peroxide.This study provides a new idea for designing porous Fe-N-C SAzymes for environmental contamination remediation. 展开更多
关键词 single-atom nanozymes(SAzymes) metal organic frameworks(MOFs) hierarchically ordered porous structure trienzyme mimics environmental contamination remediation
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Hierarchically porous N-doped carbon derived from biomass as oxygen reduction electrocatalyst for high-performance Al–air battery 被引量:3
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作者 Yanqiu Wang Jiayu Hao +5 位作者 Jiawen Yu Hongjian Yu Keke Wang Xuetao Yang Jie Li Wenzhang Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第6期119-125,I0005,共8页
Developing large-scale and highly efficient oxygen reduction reaction(ORR)catalysts acts a vital role in realizing wide application of metal–air batteries.Here,we propose a gas-foaming strategy to fabricate sustainab... Developing large-scale and highly efficient oxygen reduction reaction(ORR)catalysts acts a vital role in realizing wide application of metal–air batteries.Here,we propose a gas-foaming strategy to fabricate sustainable and 3D hierarchically porous N-doped carbon with high specific surface area and abundant defects sites derived from biomass.The obtained catalyst exhibits prominent ORR property with higher half-wave potential(0.861 V)and slightly lower kinetic current density(32.44 m A cm^-2),compared to Pt/C(0.856 V and 43.61 m A cm^-1).Furthermore,employing it as catalyst of air cathode,the Al–air battery delivers remarkable discharge performance with excellent power density of 401 m W cm^-2,distinguished energy density of 2453.4 Wh kg^-1 and extremely high open-circuit voltage of 1.85 V among the reported metal–air batteries in the literatures.This gas-foaming strategy for full utilization of biomass affords a chance to explore scalable advanced catalysts in metal–air battery. 展开更多
关键词 Gas-foaming strategy BIOMASS hierarchically POROUS structure Oxygen reduction reaction Al–air battery
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Nitrogen-rich hierarchically porous carbon foams as high-performance electrodes for lithium-based dual-ion capacitor 被引量:3
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作者 Yue Chen Xiaoming Qiu Li-Zhen Fan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第9期187-194,I0006,共9页
Nitrogen-rich porous carbonaceous materials have shown great potential in energy storage and conversion applications due to their facile fabrication,high electronic conductivity,and improved hydrophilic property.Herei... Nitrogen-rich porous carbonaceous materials have shown great potential in energy storage and conversion applications due to their facile fabrication,high electronic conductivity,and improved hydrophilic property.Herein,three-dimensional porous N-rich carbon foams are fabricated through a one-step carbonization-activation method of the commercial melamine foam,and displaying hierarchically porous structure(macro-,meso-,and micro-pores),large surface area(1686.5 m2 g^-1),high N-containing level(3.3 at%),and excellent compressibility.The as-prepared carbon foams as electrodes for quasi-solid-state supercapacitors exhibit enhanced energy storage ability with 210 F g^-1 and 2.48c at 0.1 A g^-1,and150 F g^-1 and 1.77 F cm^-2 at 1 A g^-1,respectively.Moreover,as an electrode for lithium-based dual-ion capacitor,this distinctive porous carbon also delivers remarkable specific capacitance with 143.6 F g^-1 at0.1 A g^-1 and 116.2 F g^-1 at 1 A g^-1.The simple preparation method and the fascinating electrochemical performance endow the N-rich porous carbon foams great prospects as high-performance electrodes for electrochemical energy storage. 展开更多
关键词 Nitrogen-rich Carbon foam hierarchically porous structure Dual-ion capacitor
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基于可见图的沪深股市波动分析 被引量:3
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作者 张帆 严广乐 《上海理工大学学报》 CAS 北大核心 2014年第3期250-254,263,共6页
利用可见图算法,考虑沪深股市不同时间频率(日、周、月)的收益率序列,将其映射成网络,发现所构造的网络具有分层结构和无标度性。网络节点度分布幂律指数与 Hurst 指数服从线性规律,验证了可见图算法计算 Hurst 指数的可靠性。同... 利用可见图算法,考虑沪深股市不同时间频率(日、周、月)的收益率序列,将其映射成网络,发现所构造的网络具有分层结构和无标度性。网络节点度分布幂律指数与 Hurst 指数服从线性规律,验证了可见图算法计算 Hurst 指数的可靠性。同时,截取2007~2008年沪深股市大涨大跌收益率序列,将其分别映射成网络,得出股市大涨与大跌在网络拓扑结构方面的非平凡性质。 展开更多
关键词 可见图算法 无标度性 Hurst 指数 分层结构 复杂网络
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