INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2021
·
IF 5.816
Min Mao,Jing Xu,Lingjiao Li,Sheng Zhao,Xuanhao Li
Using sunlight to catalyze water to produce H 2 is a key technology to solve the problem of energy shortage. In this research, perovskite-type NiMnO 3 and Ni 3 S 4 was recombined through secondary hydrothermal treatment . The optimal hydrogen evolution for composite materials NiMnO 3 /Ni 3 S 4 is 3.76 μmol mg −1 h −1 , that 3.7 and 4 times more than that of two monomer materials, respectively. After four cycles of catalytic experiments, proving the high efficiency and stability of the composite catalyst. The characteristics of fluorescence spectroscopy and electrochemistry have confirmed the existence of p-n heterostructures , the excellent catalytic performance is related to the built-in electric field (accelerating the separation and utilization of photocharges) generated by the combination of NiMnO 3 and Ni 3 S 4 . Strengthening the performance of the catalyst by constructing a heterostructure is an effective modification strategy and has positive application value in the fields of sensors and optoelectronics .
研究领域:
材料科学
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能源科学
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光电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Xiaobo He,Fengxiang Yin,Yanhui Li,Hao Wang,Jinnan Chen,Yanhong Wang,Biaohua Chen
This work develops the NiMnO3/NiMn2O4 ilmenite/spinel hybrid oxides as highly efficient bifunctional catalysts toward both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). They are prepared with the aid of pollen, using a two-step annealing method. The interaction between NiMnO3 and NiMn2O4 nanoparticles results in an enhanced charge transfer between nanoparticles and active species in electrolytes, which is favorable for their electrocatalytic activities. The surface oxidation states of Ni and Mn for the hybrid oxides can be tuned by pollen, which greatly influences the OER and ORR activities and the overall bifunctional activity. The surface Ni3+ facilitates OER activity, while the surface Mn3+ with a small amount of Mn4+ favors ORR processes. Through optimization, 0.61NiMnO3/NiMn2O4 shows the highest OER activity, while 1.57NiMnO3/NiMn2O4 can outperform the others in promoting ORR processes. Between them, 0.61NiMnO3/NiMn2O4 exhibits the higher overall bifunctional activity. Furthermore, both of the optimized hybrid oxides show excellent durability during both OER and ORR processes. They can be considered as promising bifunctional catalysts for OER/ORR.
研究领域:
材料化学
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电化学
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纳米催化
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能源材料
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无机功能材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Yuanting Wu,Jingyue Hu,Qiujun Liu,Xinmeng Zhang,Yunlong Xue,Bocheng Zhang,Xuhua Liu
Power density is one of the important factors affecting the performance of electrode materials, which is hampered by ion/electron transport and agglomeration build-up problems. In this study, a novel 3D NiMnO 3 /Ni(OH) 2 /Ag NWs composite is synthesized via the introduction of Ag NWs. The introduction of Ag NWs synergistically influences the crystal structure and micro-morphology of the NiMnO 3 /Ni(OH) 2 /Ag NWs composite. The unique pentatwinned structure of Ag NWs facilitates the enhancement of the (110) and (101) crystal planes, which induces the movement of Ni 2p 3/2 , leading to a significant increase of Ni 2+ concentration in the composites. This ensures an abundance of ion adsorption sites, generating materials conducive to reactive activity. This new structure increases the density of active sites and establishes a conductive network, which optimizes the electron and ion transport paths, greatly reduces the diffusion resistance at the electrode-electrolyte interface, and improves the charge transfer efficiency, thus effectively increasing the specific capacity and energy density of the material. The NiMnO 3 /Ni(OH) 2 /Ag NWs//AC device exhibits a remarkable specific capacity of 350.478 mAh·g −1 at a current density of 0.01 A cm −2 , and its Ragone plot reveals a peak energy density of 81.107 Wh kg −1 at a power density of 1699.871 W kg −1 . Additionally, it achieves an energy density of 60.532 Wh kg −1 at a power density of 8490.072 W kg −1 . This study explores the design and application of 3D structured electrode materials, which effectively improves the specific capacity of the materials and provides a new idea to further improve the energy density of supercapacitors.
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
IONICS
·
2023
·Vol. 29
·期 7
·2853-2864
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IF 2.8
Wang Wenping,Zhao Zhiyi,Deng Jiayao,Lang Wei,Zhen Lipeng,Lu Huimin
The oxygen reduction reaction of the cathode in an Al-air battery plays a key role in the performance of the entire battery. Generally, Pt and its alloys are recognized as catalysts with high oxygen reduction catalytic performance, but their application is limited by the rare earth content and high cost. In this paper, α-MnO 2 nanotubes are prepared using a hydrothermal method and used as a template. Nano-Ni–Mn bimetallic oxides with different compositions are prepared with different NiO and α-MnO 2 ratios by calcination. The effects of morphology, phase, and Mn 3+ /Mn 4+ and Ni 3+ /Ni 2+ ratios on electrochemical performance and battery discharge performance are analyzed. The results show that the contents of α-MnO 2 and Ni 6 MnO 8 in NM-12 catalyst are low, and the molar ratio of Mn 3+ /Mn 4+ and Ni 3+ /Ni 2+ is high. Also, the specific surface area of NM-12 is relatively high. Finally, the catalyst prepared with a NiO to α-MnO 2 ratio of 1:2 shows better electrochemical catalytic performance and battery discharge performance that is comparable to that obtained for a commercial 20 wt% Pt/C catalyst.
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
✓ 已验证
产品关联
DOI
高影响因子
Nanoscale
·
2023
·Vol. 15
·期 8
·4071-4079
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IF 6.7
Heen Li,Xiaoyue Xu,Xiaohu Lin,Jianmin Chen,Kunling Zhu,Fei Peng,Faming Gao
The sluggish breakage of the N–N triple bond, as well as the existence of a competing hydrogen evolution reaction (HER), restricts the nitrogen reduction reaction process. Modification of the catalyst surface to boost N2 adsorption and activation is essential for nitrogen fixation. Herein, we introduced surface oxygen vacancies in bimetal oxide NiMnO3 by pyrolysis at 450 °C (450-NiMnO3) to achieve remarkable NRR activity. The NiMnO3 3D nanosphere with a rough surface could increase catalytically active metal sites and introduce oxygen vacancies that are able to enhance N2 adsorption and further improve the reaction rate. Benefiting from the introduced oxygen vacancies in NiMnO3, 450-NiMnO3 showed excellent performance for nitrogen reduction to ammonia with a high NH3 yield of 31.44 μg h−1 mgcat−1 (at −0.3 V vs. RHE) and a splendid FE of 14.5% (at −0.1 V vs. RHE) in 0.1 M KOH. 450-NiMnO3 also shows high long-term electrochemical stability with excellent selectivity for NH3 formation. 15N isotope labeling experiments further verify that the source of produced ammonia is derived from 450-NiMnO3. The present study opens new avenues for the rational construction of efficient electrocatalysts for the synthesis of ammonia from nitrogen.
研究领域:
电化学
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催化
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材料科学
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化学工程
✓ 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）