共查询到20条相似文献,搜索用时 15 毫秒
1.
Chengzhen Wei Cheng Cheng Kaimin Wang Xiaochong Li Hecong Xiao Qiaofei Yao 《RSC advances》2021,11(25):15258
In this study, hierarchical Ni–Co–Mn hydroxide hollow architectures were successfully achieved via an etching process. We first performed the synthesis of NiCoMn-glycerate solid spheres via a solvothermal route, and then NiCoMn-glycerate as the template was etched to convert into hierarchical Ni–Co–Mn hydroxide hollow architectures in the mixed solvents of water and 1-methyl-2-pyrrolidone. Hollow architectures and high surface area enabled Ni–Co–Mn hydroxide to manifest a specific capacitance of 1626 F g−1 at 3.0 A g−1, and it remained as large as 1380 F g−1 even at 3.0 A g−1. The Ni–Co–Mn hydroxide electrodes also displayed notable cycle performance with a decline of 1.6% over 5000 cycles at 12 A g−1. Moreover, an asymmetric supercapacitor assembled with this electrode exhibited an energy density of 44.4 W h kg−1 at 1650 W kg−1 and 28.5 W h kg−1 at 12 374 W kg−1. These attractive results demonstrate that hierarchical Ni–Co–Mn hydroxide hollow architectures have broad application prospects in supercapacitors.An effective etching method is developed for the synthesis of hierarchical Ni–Co–Mn hydroxide hollow architectures, which exhibit high performance in electrochemical energy storage. 相似文献
2.
M. Anji Reddy Ben Breitung Venkata Sai Kiran Chakravadhanula M. Helen Ralf Witte Carine Rongeat Christian Kübel Horst Hahn Maximilian Fichtner 《RSC advances》2018,8(64):36802
Transition metal fluorides are an important class of cathode materials for lithium batteries owing to their high specific energy and safety. However, metal fluorides are electrical insulators, exhibiting slow reaction kinetics with Li. Consequently, metal fluorides can show poor electrochemical performance. Instead, carbon–metal fluoride nanocomposites (CMNFCs) were suggested to enhance electrochemical activity. Chemical synthesis of CMNFCs poses particular challenges due to the poor chemical stability of metal fluorides. Recently, we reported a facile one-step method to synthesize carbon–FeF2 nanocomposites by reacting fluorinated carbon (CFx) with iron pentacarbonyl (Fe(CO)5) at 250 °C. The method resulted in C–FeF2 nanocomposites with improved electrochemical properties. Here, we have synthesized four different C–FeF2 nanocomposites by reacting four different CFx precursors made of petro-coke, carbon black, graphite, and carbon-fibers with Fe(CO)5. Electrochemical performance of all four C–FeF2 nanocomposites was evaluated at 25 °C and 40 °C. It is shown that the nature of CFx has a critical impact on the electrochemical performance of the corresponding C–FeF2 nanocomposites. The C–FeF2 nanocomposites were characterized by using various experimental techniques such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, resistivity measurement, and 57Fe Mössbauer spectroscopy to shed light on the differences in electrochemical behaviour of different C–FeF2 nanocomposites.Impact of the nature of carbon on the electrochemical performance of four C–FeF2 nanocomposites derived from CFx and Fe(CO)5. 相似文献
3.
Dye-sensitized solar cells (DSSCs), different in principle from the conventional solar cells based on p–n junctions, are competitively cost-effective. For development of this kind of emerging solar cell, it is very significant to reduce their cost and improve their energy conversion efficiency to the maximum extent. In this article, ternary composites (Ni–PANI–G composites) consisting of nickel nanoparticles, polyaniline (PANI), and graphene (G) were prepared for the first time and used as counter electrodes to replace the noble metal Pt in DSSCs. In the case of PANI, the introduction of Ni nanoparticles can improve the electrocatalytic ability for the reduction of triiodide ions in the counter electrode, while in the meantime, the addition of graphene in the Ni–PANI–G composites can increase the electrical conductivity of the counter electrode. The optimized DSSCs fabricated by using the Ni–PANI–G composites as the counter electrode exhibit an overall power conversion efficiency of 5.80% compared to 5.30% for reference platinum (Pt) counter-electrodes. Electrochemical impedance spectra (EIS) show that the charge-transfer resistance at the interface between electrolyte and counter-electrode in the case of the ternary composite is obviously decreased. These results are significant to develop low-cost counter electrode materials for DSSCs.In this article, ternary composites (Ni–PANI–G composites) consisting of nickel nanoparticles, polyaniline (PANI), and graphene (G) were prepared for the first time and used as counter electrodes to replace the noble metal Pt in DSSCs. 相似文献
4.
Ying Zhang Ruidong Xu Ziyang Qin Suyang Feng Wenbin Wang Chen Chen Ao Ju 《RSC advances》2020,10(38):22422
NiO, Ni–Co–Mn–Ox and NiO/Ni–Co–Mn–Ox on nickel foam substrates were prepared via a chemical bath deposition–calcination. The thermodynamic behavior was observed by TG/DTA. The chemical structure and composition, phase structure and microstructures were tested by XPS, XRD, FE-SEM and TEM. The electrochemical performance was measured by CV, GCD and EIS. The mechanism for formation and enhancing electrochemical performance is also discussed. Firstly, the precursors such as NiOOH, CoOOH and MnOOH grow on nickel foam substrates from a homogeneous mixed solution via chemical bath deposition. Thereafter, these precursors are calcined and decomposed into NiO, Co3O4 and MnO2 respectively under different temperatures in a muffle furnace. Notably, NiO/Ni–Co–Mn–Ox on nickel foam substrates reveals a high specific capacity with 1023.50 C g−1 at 1 A g−1 and an excellent capacitance retention with 103.94% at 5 A g−1 after 3000 cycles in 2 M KOH, its outstanding electrochemical performance and cycling stability are mainly attributed to a porous sheet–sheet hierarchical nanostructure and synergistic effects of pseudo-capacitive materials and excellent redox reversibility. Therefore, this research offers a facile synthesis route to transition metal oxides for high performance supercapacitors.NiO, Ni–Co–Mn–Ox and NiO/Ni–Co–Mn–Ox on nickel foam substrates were prepared via a chemical bath deposition–calcination. 相似文献
5.
Ni–Fe–P nanoparticles/graphene nanosheet (Ni–Fe–P/GNs) composites were successfully synthesized by a simple one-step hydrothermal method. Specifically, Ni2+ and Fe2+ were reduced by using milder sodium hypophosphite as a reducing agent in aqueous solution. SEM and TEM images show that a large number of Ni–Fe–P nanoscale microspheres are uniformly deposited on graphene nanosheets (GNs). At the thickness of 3.9 mm, the minimum reflection loss (RL) of Ni–Fe–P/GNs reaches −50.5 dB at 5.3 GHz. In addition, Ni–Fe–P/GNs exhibit a maximum absorption bandwidth of 5.0 GHz (13.0–18.0 GHz) at the thickness of 1.6 mm. The significant electromagnetic absorption characteristics of the Ni–Fe–P/GN composites can be attributed to the addition of magnetic particles to tune the dielectric properties of graphene to achieve good impedance matching. Therefore, Ni–Fe–P/GN is expected to be an attractive candidate for an electromagnetic wave absorber.Ni–Fe–P nanoparticle/graphene nanosheet composites synthesized by a one-step hydrothermal method have excellent performance in the field of electromagnetic wave absorption, with a minimum reflection loss of −50.5 dB and a maximum effective absorption bandwidth of 5 GHz. 相似文献
6.
A new noble metal-free Ni–Co–P/HAP (hydroxyapatite) amorphous alloy catalyst was synthesized by an impregnation-chemical reduction method; the structure and properties of the catalysts were characterized by XRD, SEM, BET, XPS and DSC. Based on the model of the hydrodeoxygenation (HDO) of vanillin to 2-methoxy-4-methylphenol (MMP) with formic acid as a hydrogen source, the catalytic performance of the catalyst was studied. The results found that the Ni–Co–P/HAP catalyst exhibited excellent catalytic activity for the in situ HDO reaction of vanillin compared with Ni–P and Ni–Co–P. The conversion of vanillin could be high to 97.86% with MMP selectivity of 93.97% under optimized reaction conditions. In addition, mechanism studies have shown that the side reaction of carbocation and vanillyl alcohol (HMP) condensation can be effectively reduced with increasing the hydrogenation rate, thereby the selectivity of MMP was effectively increased.A new noble metal-free Ni–Co–P/HAP amorphous alloy catalyst was developed, and it showed excellent catalytic activity for in situ hydrodeoxygenation of vanillin to 2-methoxy-4-methylphenol with formic acid as a hydrogen source. 相似文献
7.
Edis Glogic Alberto Adn-Ms Guido Sonnemann Maria de Fatima Montemor Liliane Guerlou-Demourgues Steven B. Young 《RSC advances》2019,9(33):18853
Decoupling energy supply from fossil fuels through electrification and sustainable energy management requires efficient and environmentally low-impact energy storage technologies. Potential candidates are charge storage electrodes that combine nickel and cobalt hydroxides with reduced graphene oxide (rGO) designed to achieve high-energy, high-power density and long cycling lifetimes. An early eco-efficiency analysis of these electrodes seeks to examine the impacts of materials and processes used in the synthesis, specifically while focusing on the use of rGO. The emerging electrodes synthesized by means of electrodeposition, are further compared with electrodes obtained by an alternative synthesis route involving co-precipitation. Life cycle assessment (LCA) method was applied to compare a baseline nickel–cobalt hydroxide electrode (NCED), the focal electrode integrating rGO (NCED-rGO), and the benchmark co-precipitated electrode (NCCP), for delivering the charge of 1000 mA h. Contribution analysis reveals that the main environmental hotspots in the synthesis of the NCED-rGO are the use of electricity for potentiostat, ethanol for cleaning, and rGO. Results of comparison show significantly better performance of NCED-rGO in comparison to NCED across all impact categories, suggesting that improved functionalities by addition of rGO outweigh added impacts of the use of material itself. NCED-rGO is more impactful than NCCP except for the indicators of cumulative energy demand, climate change, and fossil depletion. To produce a functional equivalent for the three electrodes, total cumulative energy use was estimated to be 78 W h for NCED, 25 W h for NCED-rGO, and 35 W h for NCCP. Sensitivity analysis explores the significance of rGO efficiency uptake on the relative comparison with NCCP, and potential impact of rGO on the category of freshwater ecotoxicity given absence of removal from the process effluent. Scenario analysis further shows relative performance of the electrodes at the range of alternative functional parameters of current density and lifetime. Lastly, the environmental performance of NCED-rGO electrodes is discussed in regard to technology readiness level and opportunities for design improvements.An addition of reduced graphene oxide to nickel–cobalt hydroxide electrodes results in net reduction of cumulative energy demand due to improved electrochemical properties. 相似文献
8.
Nan Wang Sikan Peng Xiang Chen Jixian Wang Chen Wang Xin Qi Shenglong Dai Shaojiu Yan 《RSC advances》2019,9(11):6346
Lithium–sulfur batteries are attracting significant attention due to their high theoretical specific capacity and low cost. However, their applications are hindered by the poor conductivity of sulfur and capacity fading caused by the shuttle effect. Here, ultrathin manganese dioxide decorated graphene/carbon nanotube nanocomposites are designed as sulfur hosts to suppress the shuttle effect and improve the adsorption efficiency of polysulfides. The graphene/carbon nanotube hybrids, with extraordinary conductivity and large surface area, function as excellent channels for electron transfer and lithium ion diffusion. The ultrathin manganese dioxide nanosheets enable efficient chemical interaction with polysulfides and promote the redox kinetics of polysulfides. As a result, an ultrathin manganese dioxide decorated graphene/carbon nanotube sulfur composite with high sulfur content (81.8 wt%) delivers a high initial specific capacity of 1015.1 mA h g−1 at a current density of 0.1C, high coulombic efficiency approaching 100% and high capacity retention of 84.1% after 100 cycles. The nanocomposites developed in this work have promising applications in high-performance lithium–sulfur batteries.Ultrathin MnO2 nanosheets and nano size sulfur particles distributed uniformly on the surface of G/CNT hybrids, which exhibit high rate performance and long-term cycling performance. 相似文献
9.
Alejandro N. Filippin Tzu-Ying Lin Michael Rawlence Tanja Zünd Kostiantyn Kravchyk Jordi Sastre-Pellicer Stefan G. Haass Aneliia Wckerlin Maksym V. Kovalenko Stephan Buecheler 《RSC advances》2018,8(36):20304
To obtain full advantage of state-of-the-art solid-state lithium-based batteries, produced by sequential deposition of high voltage cathodes and promising oxide-based electrolytes, the current collector must withstand high temperatures (>600 °C) in oxygen atmosphere. This imposes severe restrictions on the choice of materials for the first layer, usually the cathode current collector. It not only must be electrochemically stable at high voltage, but also remain conductive upon deposition and annealing of the subsequent layers without presenting a strong diffusion of its constituent elements into the cathode. A novel cathode current collector based on a Ni–Al–Cr superalloy with target composition Ni0.72Al0.18Cr0.10 is presented here. The suitability of this superalloy as a high voltage current collector was verified by determining its electrochemical stability at high voltage by crystallizing and cycling of LiCoO2 directly onto it.A novel cathode current collector based on a Ni–Al–Cr superalloy is presented here. The suitability of this superalloy as a high voltage current collector was verified by crystallizing and cycling of LiCoO2 directly onto it. 相似文献
10.
As an emerging energy storage material, amorphous Co–Ni–B alloy was firstly introduced to construct the flexible supercapacitor electrode. To ensure the high electrochemical property, amorphous Co–Ni–B alloy and RGO sheets were combined to form the three-dimensional hierarchical structure on the surface of the cotton fabric, which was beneficial to enhance the electrochemical property. Notably, the preparation conditions of this amorphous Co–Ni–B/RGO/fabric electrode were facile and mild with room temperature and atmospheric pressure, thus avoiding serious damage to the textile fabric because of high temperature and harsh chemical reactions of most preparation methods. This flexible electrode exhibited an optimum specific capacitance of 313.9 F g−1 at 5 mV s−1 and good cycling stability with specific capacitance retention of 85.0% after 3000 cycles. Such special architecture bestowed this electrode with nice electrochemical property, in addition to great promising application in the supercapacitor field.Schematic diagram of preparation process of amorphous Co–Ni–B/RGO/cotton fabric flexible electrode. 相似文献
11.
Petri M. Leukkunen Ekta Rani Assa Aravindh Sasikala Devi Harishchandra Singh Graham King Matti Alatalo Wei Cao Marko Huttula 《RSC advances》2020,10(60):36930
P25 comprising of mixed anatase and rutile phases is known to be highly photocatalytically active compared to the individual phases. Using a facile wet chemical method, we demonstrate a ternary nanocomposite consisting of Ni and Ag nanoparticles, decorated on the surface of XTiO2 (X: P25, rutile (R)) as an efficient visible-light-driven photocatalyst. Contrary to the current perspective, RTiO2-based Ni–Ag–RTiO2 shows the highest activity with the H2 evolution rate of ∼86 μmol g−1 W−1 h−1@535 nm. Together with quantitative assessment of active Ni, Ag and XTiO2 in these ternary systems using high energy synchrotron X-ray diffraction, transmission electron microscopy coupled energy dispersive spectroscopy mapping evidences the metal to semiconductor contact via Ag. The robust photocatalytic activity is attributed to the improved visible light absorption, as noted by the observed band edge of ∼2.67 eV corroborating well with the occurrence of Ti3+ in Ti 2p XPS. The effective charge separation due to intimate contact between Ni and RTiO2via Ag is further evidenced by the plasmon loss peak in Ag 3d XPS. Moreover, density functional theory calculations revealed enhanced adsorption of H2 on Ti8O16 clusters when both Ag and Ni are simultaneously present, owing to the hybridization of the metal atoms with d orbitals of Ti and p orbitals of O leading to enhanced bonding characteristics, as substantiated by the density of states. Additionally, the variation in the electronegativity in Bader charge analysis indicates the possibility of hydrogen evolution at the Ni sites, in agreement with the experimental observations.Robust photocatalytic activity of Ni–Ag–RTiO2 is attributed to the improved visible light absorption and effective charge separation due to intimate contact between Ni and RTiO2via Ag, as evidenced by Ti3+ in Ti 2p XPS and energy dispersive mapping. 相似文献
12.
A hollow Ni–Fe–B nanochain is successfully synthesized by a galvanic replacement method using a Fe–B nanocomposite and a NiCl2 solution as the template and additional reagent, respectively. Both the concentration of Ni and the morphology of the resulting Ni–Fe–B alloy are controlled by varying the duration of the replacement process during the synthesis. The Ni–Fe–B sample synthesized for 60 min (Ni–Fe–B-60) shows the best catalytic activity at 313 K, with a hydrogen production rate of 4320 mL min−1 gcat−1 and an activation energy for the NaBH4 hydrolysis reaction of 33.7 kJ mol−1. The good performance of Ni–Fe–B-60 towards the hydrolysis of NaBH4 can be ascribed to both hollow nanochain structural and electronic effects. Furthermore, the effects of temperature, catalyst amount, and concentration of NaOH and NaBH4 on the hydrolysis process are systematically studied, and an overall kinetic rate equation is obtained. The hollow Ni–Fe–B nanochain catalyst also shows good reusability characteristics and maintained its initial activity after 5 consecutive cycles.A hollow Ni–Fe–B nanochain is successfully synthesized by a galvanic replacement method using a Fe–B nanocomposite and a NiCl2 solution as the template and additional reagent, respectively. 相似文献
13.
Daojun Zhang Jingchao Zhang Jiaqi Li Chengxiang Li Yuting Li Yingying Liu Renchun Zhang 《RSC advances》2022,12(32):20447
Porous micro/nanostructure electrode materials have always contributed to outstanding electrochemical energy storage performances. Co9S8 is an ideal model electrode material with high theoretical specific capacity due to its intrinsic two crystallographic sites of cobalt ions. In order to improve the conductivity and specific capacitance of Co9S8, nickel ions were introduced to tune the electronic structure of Co9S8. The morphology design of the mesoporous hollow sphere structure guarantees cycle stability and ion diffusion. In this work, NixCo9−xS8 mesoporous hollow spheres were synthesized via a facile partial ion-exchange of Co9S8 mesoporous hollow spheres without using a template, boosting the capacitance to 1300 F g−1 at the current density of 1 A g−1. Compared with the pure Co9S8 and Ni-Co9S8-30%, Ni-Co9S8-60% exhibited the best supercapacitor performance, which was ascribed to the maximum Ni ion doping with morphology and structure retention, enhanced conductivity and stabilization of Co3+ in the structure. Therefore, Ni/Co–Zn batteries were fabricated by using a Zn plate as the anode and Ni-Co9S8-60% as the cathode, which deliver a high energy density of 256.5 W h kg−1 at the power density of 1.69 kW kg−1. Furthermore, the Ni/Co–Zn batteries exhibit a stable cycling after 3000 repeated cycles with capacitance retention of 69% at 4 A g−1. This encouranging result might provide a new perspective to optimize Co9S8-based electrodes with superior supercapacitor and Ni/Co–Zn battery performances.Mesoporous NiCo9S8-0.6 hollow spheres as a high-performance supercapacitor and aqueous Ni/Co–Zn battery. 相似文献
14.
Xiaobo Jia Baosheng Liu Jinghua Liu Shaohui Zhang Zijun Sun Xiong He Hongda Li Guofu Wang Haixin Chang 《RSC advances》2021,11(18):10753
The practical applications of lithium–sulfur batteries are still a great challenge due to the polysulfide shuttle and capacity decay. Herein, we report a NiO–carbon nanotube/sulfur (NiO–CNT/S) composite by hydrothermal and thermal treatments. This hybrid combines the high conductivity of CNTs and double adsorption of CNTs and NiO (physical and chemical adsorption) to improve the electrochemical performance for the sulfur electrodes. Compared with CNT/S and NiO/S, the developed NiO–CNT/S composites present a preferable initial reversible discharge capacity (1072 mA h g−1) and is maintained at 609 mA h g−1 after 160 cycles at 0.1C.The NiO–CNT/S composites combine the high conductivity of CNT and double adsorption of CNT and NiO (physical adsorption and chemical adsorption) to enhance electrochemical performance for sulfur electrode materials. 相似文献
15.
The rational design of durable materials is an important issue for improving the performance of electrocatalysts towards the ethanol oxidation reaction (EOR). In this work, binderless thin nanostructured layers of SnO2, Pt, Rh, bilayers of Pt/SnO2, Rh/Pt and tri-layers of Rh (ca. 10 nm thickness)/PtSnO2 are directly grown by pulsed laser deposition onto carbon nanotubes (CNTs). SEM analysis shows that CNTs are perfectly coated with the catalysts. The onset potentials of the CO stripping and EOR indicate that Rh/Pt/SnO2 is the most active for the CO and the EOR. The incorporation of the CNTs in the catalyst layer is outstandingly beneficial to both the catalytic current activity and the durability. Indeed Rh/Pt/SnO2/CNT delivers mass activity as high as 213.42 mA mg−1Pt. Moreover, Rh/Pt/SnO2/CNT demonstrates not only the lowest poisoning rate (by intermediate species, such as adsorbed CO) but also the highest durability current of 132.17 mA mg−1Pt far superior to CNT-free Rh/Pt/SnO2/CP (58.33 mA mg−1Pt). XPS shows that SnO2, Pt and Rh are all present at the surface of Rh/Pt/SnO2/CNT, the presence of two oxophilic materials like SnO2 and Rh, implies an earlier source of OHads-species, which facilitates the oxidation of CO and assuming a second contribution from Rh is to enhance the cleavage of the C–C bond for the complete oxidation of ethanol. The 3D porous and binderless structure, the low amount of the noble catalyst, the excellent electroactivity and durability of the Rh5/PtSnO2/CNT/CP composite represents an important step in advancing its use as an anode in commercial applications in DEFC.Free-standing organized tri-layered catalyst Rh–Pt–SnO2-carbon nanotubes for electrochemical energy conversion application. The electrode exhibits an enhanced electrocatalytic activity and durability towards ethanol oxidation. 相似文献
16.
Fei-Hong Kuok Hung-Hua Chien Chia-Chun Lee Yu-Chuan Hao Ing-Song Yu Cheng-Che Hsu I-Chun Cheng Jian-Zhang Chen 《RSC advances》2018,8(6):2851
This study evaluates DC-pulse nitrogen atmospheric-pressure-plasma-jet processed carbon nanotube (CNT)–reduced graphene oxide (rGO) nanocomposites for gel-electrolyte supercapacitor applications. X-ray photoelectron spectroscopy (XPS) indicates decreased oxygen content (mainly, C–O bonding content) after nitrogen APPJ processing owing to the oxidation and vaporization of ethyl cellulose. Nitrogen APPJ processing introduces nitrogen doping and improves the hydrophilicity of the CNT–rGO nanocomposites. Raman analysis indicates that nitrogen APPJ processing introduces defects and/or surface functional groups on the nanocomposites. The processed CNT–rGO nanocomposites on carbon cloth are applied to the electrodes of H2SO4–polyvinyl alcohol (PVA) gel-electrolyte supercapacitors. The best achieved specific (areal) capacitance is 93.1 F g−1 (9.1 mF cm−2) with 15 s APPJ-processed CNT–rGO nanocomposite electrodes, as evaluated by cyclic voltammetry under a potential scan rate of 2 mV s−1. The addition of rGOs in CNTs in the nanoporous electrodes improves the supercapacitor performance.This study demonstrates ultrafast (15 s) atmospheric-pressure-plasma-jet (APPJ) processed CNT–rGO nanocomposite gel-electrolyte supercapacitors. 相似文献
17.
In this paper, a series of novel dithioacetal–naphthalenes were designed and synthesized for plant immunity. Their antiviral activities were evaluated against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV). The results indicated that most compounds exhibited better activity against CMV than against TMV. These dithioacetal derivatives also displayed good bacterial activity against rice bacterial leaf blight. Among them, compound S16 exhibited relatively good anti-CMV, anti-TMV, and antibacterial activity. Structure–activity relationships indicated that introducing the naphthalene moiety enhanced their activities for plant resistance induction. Therefore, the basic motif of compound S16 could be the most promising candidate for further structural optimization to develop a potential activator for plant resistance induction.In this paper, a series of novel dithioacetal–naphthalenes were designed and synthesized for plant immunity. 相似文献
18.
The control of structure and morphology in an electrode design for the development of large-power lithium ion batteries is crucial to create efficient transport pathways for ions and electrons. Herein, we report a powerful combinational strategy to build omnibearing conductive networks composed of titanium niobium oxide nanorods and carbon nanofibers (TNO/CNFs) via an electrostatic spinning method and a hydrothermal method into free-standing arrays with a three-dimensional heterostructure core/shell structure. TNO/CNF electrode exhibits significantly superior electrochemical performance and high-rate capability (241 mA h g−1 at 10C, and 208 mA h g−1 at 20C). The capacity of the TNO/CNF electrode is 257 mA h g−1 after 2000 cycles at 20C, which is much higher than that of the TNO electrode. In particular, the TNO/CNF electrode delivers a reversible capacity of 153.6 mA h g−1 with a capacity retention of 95% after 5000 cycles at ultrahigh current density. Superior electrochemical performances of the TNO/CNF electrode are attributed to the unique composite structure.The control of structure and morphology in an electrode design for the development of large-power lithium ion batteries is crucial to create efficient transport pathways for ions and electrons. 相似文献
19.
Dicky Annas Shamim Ahmed Hira Sehwan Song Jong-Seong Bae Sungkyun Park Kang Hyun Park 《RSC advances》2021,11(52):32965
Mixed metal–metal oxide/C (Ag–Cu–Cu2O/C) nanocomposites were synthesized by the heat treatment of a metal–organic framework under a N2 flow using the one-pot synthesis method. The as-prepared nanocomposites were characterized using a range of techniques, such as TEM, elemental mapping, XRD, N2 sorption, UV-Vis DRS, and XPS. The nanoparticles were successfully formed with high dispersion in porous carbon materials and high crystallinity based on the analysis results. The Ag–Cu–Cu2O/C nanocomposites (35 nm) showed high photocatalytic activity and good recyclability toward the borylation of aryl halides under a xenon arc lamp. This result can enhance the interest in photocatalysis for various applications, particularly in organic reactions, using a simple and efficient synthesis method.Ag–Cu–Cu2O/C nanocomposites derived from metal–organic framework through one-pot thermal reduction method were synthesized. The material exhibits high catalytic activity in the borylation of aryl halide under xenon lamp condition across 7 cycles, with no yield decrease. 相似文献
20.
Jinlei Xie Yefeng Yang Geng Li Hanchun Xia Peijia Wang Peiheng Sun Xiaolong Li Haoran Cai Jie Xiong 《RSC advances》2019,9(6):3041
To obtain high-performance hybrid supercapacitors (HSCs), a new class of battery-type electrode materials with hierarchical core/shell structure, high conductivity and rich porosity are needed. Herein, we propose a facile one-step sulfuration approach to achieve the fabrication of hierarchical NiCo2S4@NiCo2S4 hybrid nanotube/nanosheet arrays (NTSAs) on carbon cloth, by taking hydrothermally grown Ni–Co precursor@Ni–Co precursor nanowire/nanosheet arrays (NWSAs) as the starting templates. The optimized electrode of NiCo2S4@NiCo2S4 hybrid NTSAs demonstrates an enhanced areal capacity of 245 μA h cm−2 at 2 mA cm−2 with outstanding rate capability (73% from 2 to 20 mA cm−2) and cycling stability (86% at 10 mA cm−2 over 3000 cycles). In addition, flexible solid-state HSC devices are assembled by using NiCo2S4@NiCo2S4 hybrid NTSAs and activated carbon as the positive and negative electrodes, respectively, which manifest a maximum volumetric energy density of 1.03 mW h cm−3 at a power density of 11.4 mW cm−3, with excellent cycling stability. Our work indicates the feasibility of designing and fabricating core/shell structured metal sulfides through such a facile one-step sulfuration process and the great potential of these materials as advanced electrodes for high-performance HSC devices.One-step sulfuration synthesis of NiCo2S4@NiCo2S4 core–shell arrays on carbon cloth. 相似文献