Materials Today Chemistry
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2022
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IF 7.613
Ying Liang,Tian Xia,Zhuangzhuang Wu,Yingjie Yang,Yongpeng Li,Zhuyin Sui,Chaokun Li,Ruimei Fan,Xinlong Tian,Qi Chen
The search for functionalized covalent organic framework (COF) materials is significant on account of their great promise for frontline applications in various fields. Herein, a novel and convenient tactic is developed to design and fabricate the tetrazole-functionalized COF materials with abundant nitrogen atoms, which can provide active sites, facilitating the incorporation of COFs with metal ions. In particular, a β -ketoenamine-linked COF named COF-TpDb is selected as precursor for postsynthetic modification to introduce the tetrazole moieties to coordinate with metal ions cobalt (Co 2+ ) and palladium (Pd 2+ ), giving two functional metal-coordinated COFs complexes COF-TpDb-TZ-Co and COF-TpDb-TZ-Pd. The resultant COF-TpDb-TZ-Co displays a higher oxygen evolution reaction activity with a lower overpotential of 390 mV at a current density of 10 mA cm −2 , which is much enhanced compared with COF-TpDb-TZ. The tactic for the fabrication of tetrazole-functionalized COFs with abundant nitrogen atoms implements rational design for the construction of functional COFs and expands the promising application of metal-coordinated COF materials in electrocatalysis .
研究领域:
材料科学
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电化学
·
催化
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2023
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IF 7.2
Fushan Wen,Le Pang,Tao Zhang,Xiaoli Huang,Yuan Xu,Yajie Li
The exploitation of the superior oxygen evolution reaction (OER) electrocatalysts is of great paramount importance to the investigation of developing hydrogen production from water splitting to alleviate the energy crisis. Herein, Fe 3+ ion doped NiS 2 for OER electrocatalysts obtained from a metal-organic framework (MOF) as a self-template, with the graphitic phase carbon nitride (g-C 3 N 4 ) as a chain armor, was prepared by the two-step solvothermal-pyrolysis method. The MOF-derived Fe–NiS 2 @g-C 3 N 4 composite achieves a current density of 10 mA cm −2 at a tiny OER overpotential (280 mV) and shows good stability in duration tests over 60 h. Compared with the undoped sample, the overpotential is significantly lower by 60 mV and the stability is substantially improved. In this study, two strategies, iron ion doping and g-C 3 N 4 coating, were implemented to target the defects of NiS 2 , promoting its catalytic activity and achieving a significant improvement in stability at the cost of a bit of activity. Balancing activity and stability maximized has been achieved by our work. This study presents a potential approach to improve the catalyst activity and stability in an integrated strategy.
研究领域:
材料科学
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能源化学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2020
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IF 10.652
Yulin Xing,Jiangang Ku,Weng Fu,Lianzhou Wang,Huihuang Chen
Oxygen evolution reaction (OER) remains the bottleneck of many energy transformation and storage technologies due to the sluggish kinetics. Transition-metal (TM) hydroxide nanosheets with high-valent TM ions possess high intrinsic catalytic activity toward OER. Herein, by taking advantage of the inductive effect, this work presents a facile and universal strategy to fabricate atomic iridium (Ir) incorporated TM hydroxide nanosheets as highly active OER electrocatalysts . As a representative, the fabricated Ir-Ni(OH) 2 (4 wt% Ir) exhibits remarkable OER performance with a low overpotential (235 mV at 10 mA cm −2 ), a small Tafel slope (58.4 mV dec −1 ), and excellent durability (60 h) in alkaline solution, significantly outperforming the benchmark IrO 2 and Ni(OH) 2 . Mechanism studies unveil that the inductive effect between Ni and Ir endows Ni(OH) 2 with high-valent Ni species, which facilitate the adsorption of nucleophilic intermediates and boost the OER activity and long-term stability of Ir-Ni(OH) 2 . More importantly, the reported strategy could be extended to synthesize other monometallic/bimetallic TM hydroxide nanosheets (Co, CoMn) as highly efficient OER electrocatalysts. This work should pave a universal and promising avenue to rationally design and controllably synthesize efficient yet robust OER electrocatalysts in energy-related fields.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2023
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IF 6.2
Yuanjun Liu,Yuyu Liu,Binbin Li,Xingmei Guo,Junhao Zhang,Guoxing Zhu
Rational reconstruction of oxygen evolution reaction (OER) pre-catalysts and the performance index is crucial but still challenging. Herein, a coordination compound composed by ferrocenedicarboxylic acid and Co 2+ was prepared, which was then treated by NaBH 4 solution for the rational reconstruction. The electrochemical activation of the treated product results in the generation of oxyhydroxides with unique microstructure acting as the catalytic active phase, which exhibits excellent electrocatalytic activity with a low overpotential of 256 mV for 10 mA cm −2 towards OER and a half-wave potential of 0.69 V ( vs RHE) for oxygen reduction (ORR). Ru species was then loaded on the treated product to further improve the catalytic activity for oxygen reduction. The annealed product (Ru-CoFe/C) presents a core-shell structure with carbon layer on the surface. The product presents an increased half-wave potential of 0.744 V ( vs RHE) for ORR with the OER/ORR overpotential gap of 0.776 V for 10 and 1 mA cm −2 , respectively, showing the bifunctional catalytic activity. Ru species with small size improves the catalytic activity for ORR; the carbon shell provides the high stability. A Zn-air battery was then fabricated with the Ru-CoFe/C catalyst, which delivers a high power density of 88 mW cm −2 and a large specific capacity of 709 mAh g −1 , as well as an excellent cycling stability over 65 h, surpassing commercial Pt/C + RuO 2 based counterpart, demonstrating its feasibility in the field of renewable electronic devices. This work affords valuable guidelines for the application of ferrocene-based materials in OER and for the exploring of advanced bifunctional ORR/OER catalysts in rational construction of high-quality Zn-air batteries.
研究领域:
材料科学
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电化学
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能源存储与转换
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DOI
高影响因子
Nature Communications
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2019
·Vol. 10
·期 1
·1-11
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IF 11.878
Ma Kaijie,Zhang Yunong,Liu Le,Xi Jingyu,Qiu Xinping,Guan Tian,He Yonghong
Understanding spatial distribution difference and reaction kinetics of the electrode is vital for enhancing the electrochemical reaction efficiency. Here, we report a total internal reflection imaging sensor without background current interference to map local current distribution of the electrode in a vanadium redox flow battery during cyclic voltammetry (CV), enabling mapping of the activity and reversibility distribution with the spatial resolution of a single fiber. Three graphite felts with different activity are compared to verify its feasibility. In long-term cyclic voltammetry, the oxygen evolution reaction is proved to enhance activity distribution, and homogeneity of the electrode and its bubble kinetics with periodic fluctuation is consistent with the cyclic voltammetry curve, enabling the onset oxygen evolution/reduction potential determination. Higher activity and irreversibility distribution of the electrode is found in favor of the oxygen evolution reaction. This sensor has potential to detect in situ, among other processes, electrochemical reactions in flow batteries, water splitting, electrocatalysis and electrochemical corrosion.
研究领域:
电化学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）