APPLIED ORGANOMETALLIC CHEMISTRY
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2020
·Vol. 34
·期 10
·e5814
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IF 3.14
Yongcen Lin,Xue Dong,Lang Zhao
N-ZIF-(1:0)@NiCo-LDH, N-ZIF-(1:3.5)@NiCo-LDH and N-ZIF-(0:1)@NiCo-LDH were prepared by mixing solvents in various volume ratios ( V methanol : V water = 1:0, 1:3.5 and 0:1) when synthesizing precursors. These composite materials were characterized using scanning and transmission electron microscopies, X-ray diffraction, X-ray photoelectron spectroscopy and nitrogen adsorption–desorption measurements, and investigated as catalysts for reduction of 4-nitrophenol, methyl orange and methylene blue. The NaBH 4 concentration as an important factor that may affect catalytic activity for reduction of 4-nitrophenol was examined. Under optimal experimental conditions, the excellent catalytic activity of the N-ZIF-(0:1)@NiCo-LDH composite, compared to that of N-ZIF-(1:0)@NiCo-LDH and N-ZIF-(1:3.5)@NiCo-LDH composites, could be attributed to the presence of graphitic nitrogen. In addition, compared with previously reported catalysts, all catalysts prepared show excellent catalytic activity owing to the unique structure exposing more active sites.
研究领域:
材料科学
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环境化学
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催化化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 47
·22830-22840
·
IF 3.925
Jiajun Nong,Yuexiang Jin,Jun Tan,Hongxia Ma,Yuan Lian
Realizing highly efficient utilization of solar energy for solving problems of environmental pollution and energy shortage has attracted increasing attention. Herein, Z-scheme two-dimensional (2D)/2D NiCo-LDH/g-C3N4 (LDH/CN) heterojunction composites were synthesized, which showed enhanced photocatalytic performance for tetracycline hydrochloride (TC) degradation and hydrogen (H2) generation under visible light irradiation. A 2D/2D heterojunction structure was formed between NiCo-LDH nanosheets (LDH) and g-C3N4 (CN), which was beneficial for the effective separation of photogenerated charge carriers. The active species of hydroxyl (˙OH), superoxide (˙O2−) and hole (h+) radicals contributed to TC photodegradation. The optimum photocatalyst showed a remarkably enhanced photocatalytic capability with a hydrogen generation rate of 451.7 μmol g−1 h−1. The improved photocatalytic activities may be attributed to the synergistic effects of the increased absorption of visible light, the separation efficiency of carriers and the 2D/2D heterostructure. A Z-scheme photocatalytic mechanism was proposed for the LDH/CN composite, showing dual advantages of a high redox ability and efficient charge carrier separation.
研究领域:
材料科学
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环境科学
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能源科学
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DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
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2025
·
IF 19
Liuxu Wei,Yupeng Wang,Ruihan Gao,Jiapei Liu,Qi Zhang,Jun Xing,Xiaodan Xia,Zhenyu Xiao,Lei Wang
Although layered double hydroxides (LDHs) provide structural advantages for alkaline zinc-ion battery (AZIB) cathodes via their inherent layered architecture, their intrinsic low electrical conductivity and anisotropic ion transport limits charge transfer kinetics. A Ksp -regulated electrochemical etching strategy is first proposed to solve this challenge by exploiting the dramatic solubility difference between BaSO 4 and Co/NiSO 4 . The thermodynamic selectivity enables the precise construction of BaSO 4 nanodot-anchored NiCo-LDH heterostructures (BS@CN-LDH) within a rapid minute-scale process, achieving atomic-level control over heterointerface architecture. Density functional theory (DFT) calculations coupled with UPS analysis reveal a strong built-in electric field (BEF) at the heterointerface (ΔΦ = 0.70 eV), driving interfacial charge redistribution of 0.013 e from NiCo-LDH to BaSO 4 . The optimized BS@CN-LDH electrode material exhibits a high specific capacity of 450.5 mAh g −1 at a current density of 2 mA cm −2 , maintaining 83.3% excellent cycling stability after 10 000 cycles. Moreover, the as-fabricated BS@CN-LDH//rGO-Zn AAZB cell achieves a record energy density of 747.9 Wh kg −1 at a power density of 0.27 kW kg −1 , surpassing most reported zinc-based energy storage devices. This Ksp -regulated etching strategy provides critical insights into electric field engineering of heterostructured materials to resolve the persistent electron/ions transfer kinetics for dramatically increased energy storage performance.
研究领域:
材料科学
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电化学
·
能源存储
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DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·
IF 10.7
Hongtao Zhou,Xuefeng Sha,Fan Zeng,Xueli Wu,Minghao Yu,Zhidan Shi,Xingang Zhang,Xianyin Song,Changzhong Jiang
Nickel–cobalt layered double hydroxide (NiCo-LDH) is a promising electrode material for supercapacitors due to its high electrochemical activity. However, it easily restacks and aggregates due to its nanosheet structure, which limits the effective utilization of redox active sites. Herein, the NiCo-LDH nanosheets derived from ZIF-67 were in situ grown on the surface of a basic copper cobalt carbonate (CoCu) urchin-like skeleton and supported by nickel foam (CoCu@NiCo-LDH). The well-designed three-dimensional (3D) hierarchical nanostructure not only effectively prevents the aggregation of NiCo-LDH nanosheets, but also provides a rapid charge transport channel, which facilitates ion diffusion and electron transport, therefore enhancing the utilization of NiCo-LDH redox active sites to a greater extent. Besides, the synergistic interactions between NiCo-LDH nanosheets and CoCu nanoneedles further enrich the redox reactions and increase the electrical conductivity and reaction kinetics of the electrode at the same time. As a result, the CoCu@NiCo-LDH electrode exhibits outstanding electrochemical performance with an ultrahigh mass loading of 14 mg cm−2, including excellent specific capacitance (18.71 F cm−2 or 1346 F g−1 at 3 mA cm−2) and distinguished rate capability of 87.3% from 3 mA cm−2 to 50 mA cm−2. When the CoCu@NiCo-LDH electrode was assembled with active carbon (AC) to form an asymmetric supercapacitor (ASC), the CoCu@NiCo-LDH//AC ASCs display outstanding energy density (1.98 mW h cm−2) and power density (97.5 mW cm−2) with excellent cycling stability (86.0% initial capacitance after 5000 cycles), and could keep an LED light bulb working for 90 min after only charging for 60 s. This work provides an effective strategy for the design and application of layered double hydroxide based pseudocapacitors.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
FuYin Lan,HaiYan Zhang,Jinchen Fan,Qunjie Xu,Hexing Li,YuLin Min
Herein, we introduce polymer nanofibers of TiO2@NiCo-LDH as interlayers into Li–S batteries. From 0 to 60 °C, the interlayers can deliver high sulfur utilization, an outstanding rate capability, and excellent cycling life. High-temperature excitation makes it easier for the valence band electrons of TiO2 to transition to the conduction band. The electron–hole pairs formed on the surface combine with the ether group of 1,3-dioxolane in the electrolyte, which greatly reduces the decomposition and volatilization rates of the electrolyte, ensuring Li–S batteries with good cycle performance at high temperatures. The capacity can stabilize at 798.6 mAh g–1 after 100 cycles at 60 °C and 1C, and the battery can provide a capacity higher than 323.2 mAh g–1 at 0 °C. Simultaneously, the lithium metal symmetrical battery with a functional separator can be continuously cycled for 1800 and 750 h without a short circuit at the current densities of 0.65 and 1.63 mA cm–2, respectively.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2024
·
IF 5.8
Chenglong Liu,Jiacheng Jin,Fan Dong,Zhipeng Zhang,Daolin Zhou,Mingxin Jin,Haohao Wan,Min Shao,Yushan Wan
This article aims at preparing of Z-scheme heterojunction NiCo-LDH/Bi 2 WO 6 (LDH: layered double hydroxides) via a solvothermal technique, addressing the rapid recombination of electron-hole pairs caused by the narrow bandgap of Bi 2 WO 6 . Successful loading of NiCo-LDH onto Bi 2 WO 6 was confirmed through various characterization techniques, assessing the composite's crystal structure, morphological traits, and performance. Notably, the NiCo-LDH/Bi 2 WO 6 composite exhibited excellent photocatalytic performance in the degradation of tetracycline (TC), achieving an optimal reaction rate of 0.03 min −1 , which is 4.8 times faster than that of Bi 2 WO 6 alone. The findings demonstrate that the formation of the heterojunction structure facilitated the separation of photogenerated electron-hole pairs by reducing recombination in monomers. Free radical trapping experiments showcased that the decomposition of TC is primarily driven by h + and ∙O 2 − . Additionally, liquid chromatography-mass spectrometry analysis identified the degradation products of TC and suggested two potential degradation pathways. The present research provides a novel approach for preparing LDH photocatalytic materials using NiCo-LDH/Bi 2 WO 6 .
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2020
·Vol. 8
·期 35
·18106-18116
·
IF 11.301
Tuo Wang,Huimin Wu,Chuanqi Feng,Lei Zhang,Jiujun Zhang
Water electrolysis is an important way to produce hydrogen at the cathode, but the oxygen evolution reaction (OER) at the anode has a high overpotential. Using the urea oxidation reaction (UOR) to replace OER has been an energy-saving approach for its lower electrode potential, and also a potential approach for wastewater treatment. In this paper, novel materials of MoP@NiCo-LDH/NF-x (x = 10, 20, 30 minutes) are synthesized and explored as bifunctional catalysts for both the hydrogen evolution reaction (HER) at the cathode and the urea oxidation reaction (UOR) or the oxygen evolution reaction (OER) at the anodes of urea–water or water electrolysis. The morphologies and compositions of such catalyst materials are characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. The catalytic activity and stability are measured by linear sweep voltammetry, electrochemical impedance spectroscopy, chronoamperometry, etc. The results indicate that MoP@NiCo-LDH/NF-20 has better catalytic performance, and can be used as a bifunctional catalyst for both HER and OER/UOR in the electrolysis. A two-electrode electrolyser (MoP@NiCo-LDH/NF-20‖MoP@NiCo-LDH/NF-20) is constructed. At 100 mA cm−2, the two-electrode electrolyser needs only 1.405 V, while the precious metal electrolyser Pt/C/NF‖IrO2/NF needs 1.697 V at the same current density, indicating that MoP@NiCo-LDH/NF-20 could be a promising bifunctional electrocatalyst in water and urea–water electrolysis for the treatment of urea wastewater and hydrogen production.
研究领域:
材料科学
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电化学
·
能源转化与储存
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2023
·
IF 8.8
Xin Tang,Shan Zhao,Jiaying Wu,Zhiyuan He,Yu Zhang,Ke Huang,Zhirong Zou,Xiaoli Xiong
It is necessary to efficient detection hydrazine in food . Exploring highly sensitive, low-cost and fast response electrochemical hydrazine sensing methods has been a challenge in this field. In this paper, a conformal transformation method is used to prepare rose flower-like NiCo-LDH derivating from the bimetallic NiCo-MOFs, and the N 2 H 4 sensing platform with a large electrocatalytic area, high conductivity and good stability was constructed. Based on the synergy between Ni and Co and the remarkable catalytic activity of the rough 3D flower-like structure, the N 2 H 4 sensor has a linear response in the concentration range of 0.001–1 mmol/L and 1–7 mmol/L, with a sensitivity of 5342 μA L mmol −1 cm −2 and 2965 μA L mmol −1 cm −2 (S/N = 3), respectively, and low limit of detection of 0.043 μmol/L. This study opens a new door for the successful application of electrochemical sensors to detect N 2 H 4 in real food samples.
研究领域:
材料科学
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分析化学
·
食品安全
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2020
·
IF 6.182
M. Usman Tahir,Hina Arshad,Wenyu Xie,Xianglong Wang,Muhammad Nawaz,Chao Yang,Xintai Su
Dodecahedral imidazolium framework-67 (ZIF-67) is synthesized in aqueous solution and used as a sacrificial template for the synthesis of uniform three-dimensional (3-D) hierarchical hexagonal flower-like nickel–cobalt layered double hydroxides (NiCo-LDH) by facile hydrothermal treatment. TEM and SEM results reveal that each microflower is composed of abundant two-dimensional (2D) ultrathin wrinkled nanosheets. The induction of 2,3,5,6-terafluroterephthalic acid (H 2 tfbdc) and hexamethylenetetramine (HMT) as an additive along with nickel nitrate hexahydrate plays a vital role to tune uniform hierarchical morphology and augmented electrochemical performance. The supercapacitor performance results show that (NiCo-LDH)S HH electrode has the best supercapacitor performance when it is used as a pseudo-capacitor. The maximum specific capacitance is 1765 F g −1 at the current density of 1 A g −1 with stable cycling performance. An asymmetric supercapacitor device assembled using (NiCo-LDH)S HH as the positive and activated carbon (AC) as the negative electrode attains a high energy density of 53.31 Wh kg −1 at a power density of 749.7 W kg −1 with 84.3% capacitance retention after 6000 cycles. This work provides a novel route for the design and synthesis of two-component hydrotalcite with 2D nanosheets having a large interlayer spacing of 9.3 d(Å) and its potential application in electrochemical energy storage.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Storage
·
2024
·
IF 8.9
Yu-Gang Fu,Yi-Han Li,Qiu-Feng Lü
Nickel‑cobalt layered double hydroxide (NiCo-LDH) has received much attention in the field of supercapacitor electrodes due to its multiple oxidation states and good electrochemical activity. However, NiCo-LDH often suffers from structural instability and low conductivity in practical applications. In this study, sea urchin-like structural NiCo-LDH coated cobalt‑nitrogen co-doped carbon (NiCo-LDH@Co-NC-x) electrode materials were prepared by in situ growth of NiCo-LDH on the surface of cobalt‑nitrogen co-doped carbon nanosheets (Co-NC) using a one-step hydrothermal method. The results show that the NiCo-LDH@Co-NC-2 electrode material exhibits excellent electrochemical performance, its specific capacitance is up to 1909 F g −1 at a current density of 1 A g −1 , and capacitance retention of 69.5 % (only 26.2 % for NiCo-LDH) can be achieved after 10,000 cycles at a current density of 10 A g −1 . This is because the abundant and uniformly distributed Co nanoparticles on Co-NC provide nucleation sites for the in-situ growth of NiCo-LDH, effectively improving the interface binding between Co-NC and NiCo-LDH, enhancing the structural stability of NiCo-LDH, and ensuring highly efficient electron transport throughout the NiCo-LDH@Co-NC-2 electrode. An asymmetric supercapacitor (NiCo-LDH@Co-NC-2//AC) was further assembled with NiCo-LDH@Co-NC-2 and activated carbon (AC) as positive and negative electrodes, respectively, achieving an energy density as high as 36.8 Wh kg −1 at a power density of 750 W kg −1 . These findings suggest that the NiCo-LDH@Co-NC-2 composite can be a promising candidate for high-performance supercapacitor electrode.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Chi Zhang,Zhixiao Zhu,Yanke Zhang,Weixuan Shao,Di Wu,Guannan Peng,Zhengchun Liu
In-plane micro-supercapacitors (IMSCs) have greater promise for use in flexible wearable electronics than traditional stacked configurations due to their ease of integration and conformability. Nickel-cobalt layered double hydroxide (NiCo-LDH) has garnered significant interest as a stellar material for supercapacitors because of its affordable price, regular morphology, and high theoretical capacity. Unfortunately, the intrinsic poor conductivity of LDH materials prevents supercapacitors from achieving long-term stable cycling and the desired energy density. This research successfully applies the self-templated approach to prepare carbon nanotubes (CNTs) with heterogeneous architectures and numerous phase interfaces, thereby mitigating this disadvantage. Carbon nanosheets adorned with WO 2 and MoO 2 nanoparticles assemble the CNT with a typical three-dimensional structure. When combined with LDH in a suitable ratio, the composite electrode’s conductivity significantly improves, providing increased capacity and cycling stability. Compared to commercial CNTs , the larger size of the prepared WO 2 /MoO 2 @P, N-CNTs serves a superior supporting and connecting role, thereby preventing the NiCo-LDH from aggregating. Under the best conditions, the composite electrode demonstrates a capacity of 1237 C/g at 1 A g −1 and an optimal capacity retention of more than 92%. For the IMSC devices, the composite materials as the positive electrode achieve an energy density of 0.0590 mWh cm −2 , and no capacity degradation is observed after 10,000 cycles. In addition, bending tests have demonstrated the mechanical stability of the IMSCs. Therefore, this strategy of mixing highly conductive WO 2 /MoO 2 @P, N-CNTs can effectively improve the conductivity of the composite material and the mechanical properties of the overall device. Furthermore, this concept can be further extended to the preparation and application of other wearable devices.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
Advanced Composites and Hybrid Materials
·
2025
·Vol. 8
·期 2
·1-15
·
IF 21.8
Zhao Weigang,Deng Jianping,Li Menghan,Du Guanben,Fan Mizi,Gao Haili,Yuan Zhanhui
In this study, tannin-derived porous carbon (TAC) with different microstructures was prepared via a microwave hydrothermal method, followed by KOH activation. Subsequently, the sea urchin–like NiCo-LDH/Tannin-derived carbon-based microsphere composite materials were rationally synthesized through a single-step microwave hydrothermal co-assembly process. The physicochemical characteristics and supercapacitive performance were systematically analyzed. TAC with a microspherical structure promoted and controlled the growth of LDHs, resulting in a more regular sea urchin–like structure, improved dispersibility, reduced resistance, and increased active sites. NiCo-LDH@TAC600-0 (without KOH activation) as an electrode material delivered a specific capacitance (Cs) of 1250 F g −1 at 1 A g −1 and 1035 F g −1 at 10 A g −1 , with a rate performance of 82.8%. The asymmetric supercapacitor device using NiCo-LDH@TAC600-0 and TAC provided an energy density of 30.8 Wh kg −1 at 800 W kg −1 and a capacitance retention rate of 72.5% after 5000 cycles. This study offers a novel approach to enhancing NiCo-LDH properties for efficient energy storage.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子