Journal of Physical Chemistry C
·
2021
·
IF 4.126
Yao Li,Le Xin Song,Wei Ping Wang,Yue Teng,Juan Xia,Nan Ning Liu
In this work, we prepared a series of Fe-MOF polyhedra [metal organic framework (MOF)-1 ∼ −13] by introducing β-cyclodextrin (CD) as a morphology modifier using an interaction between ferric chloride and terephthalic acid in dimethylformamide. A novel structural evolution from a hexagonal bipyramid to a bipyramidal hexagonal prism was clearly observed. This evolution was gradual and could be well reflected by the height ratio of the prism and pyramid in these polyhedral structures. It is the relative concentration of β-CD that drives this structural evolution. Although the reaction temperature and time can also affect the height ratio to some extent, their influence can only be realized in the presence of β-CD. In the absence of β-CD, only hexagonal bipyramid structures were obtained. It is worth noting that Fe-MOF-1 with a bipyramidal hexagonal prism structure (prism height, ∼130 nm) showed typical paramagnetic characteristics, and its saturation magnetization was determined to be 23.1 emu·g–1. Furthermore, we found that Fe-MOF-1 exhibited good photocatalytic performance for different types of dyes (crystal violet with positives and methyl orange with negative charges). At the same time, a possible photocatalytic mechanism was proposed to explain the difference of degradation efficiency between the two dyes. Also, we use the combination of specific surface area and zeta potential to explain the differences in the catalytic properties of a series of Fe-MOF materials. In addition, MOF-1 shows the same electrocatalytic oxygen evolution reaction performance as some bimetallic MOFs such as Fe-Co-MOF. For example, the overpotential of MOF-1 is 398 mV at 10 mA·cm–2 current density, while that of Fe-Co-MOF is 410 mV. We believe that the current work can contribute to the adjustment, modification, and application of MOF nanostructures.
研究领域:
材料科学
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化学工程
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环境科学
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产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2018
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IF 4.229
Chongjun Zhao,Pengwei Li,Danmin Shao,Ruizhi Zhang,Shengqi Wang,Zhaoqiang Zhu,Chunhua Zhao
A phytic acid-derived Co 2-x Ni x P 2 O 7 -C/RGO composite was designed and facilely synthesized, in which phytic acid acted as both a phosphoric source and carbon source. Both carbon derived from phytic acid and reduced graphene oxide (RGO) in composite, enhanced the conductivity and thus improve its electrocatalytical capability. As-synthesized Co 1.22 Ni 0.78 P 2 O 7 -C/RGO composite exhibited excellent oxygen evolution reaction (OER) catalytic performances: At the current density of 10 mA cm −2 , only a low overpotential of 283 mV and a small Tafel slope of 51 mV dec −1 were observed. Good OER catalytic performance was retained even after 10 h continuously running at a constant voltage, which is even comparable to those of first-rate noble metal catalyst RuO 2 . In addition, the performances of Co 2-x Ni x P 2 O 7 -C/RGO catalysts were also strongly dependent on Ni content.
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
Small
·
2023
·Vol. 19
·期 10
·2206698
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IF 13.3
Tongtong Liu,Hengyu Guo,Yanan Chen,Zhengping Zhang,Feng Wang
Pyrochlore ruthenate (Y 2 Ru 2 O 7–δ ) is highlighted as a promising oxygen evolution reaction (OER) catalyst for water splitting in polymer electrolyte membrane electrolyzers. However, an efficient electronic modulation strategy for Y 2 Ru 2 O 7–δ is required to overcome its electrochemical inertness. Herein, a surface manipulation strategy involving implanting MoO x moieties on nano Y 2 Ru 2 O 7–δ (Mo–YRO) using wet chemical peroxone method is demonstrated. In contrast to electronic structure regulation by intramolecular charge transfer (i.e., substitutional strategies), the heterogeneous Mo−O−Ru micro-interfaces facilitate efficient intermolecular electron transfer from [RuO 6 ] to MoO x . This eliminates the bandgap by inducing Ru 4 d delocalization and band alignment rearrangement. The MoO x modifiers also alleviate distortion of [RuO 6 ] by shortening Ru−O bond and enlarging Ru−O−Ru bond angle. This electronic and geometric structure tailoring enhances the OER performance, showing a small overpotential of 240 mV at 10 mA cm −2 . Moreover, the electron-accepting MoO x moieties provide more electronegative surfaces, which serve as a protective “fence” to inhibit the dissolution of metal ions, thereby stabilizing the electrochemical activity. This study offers fresh insights into the design of new-based pyrochlore electrocatalysts, and also highlights the versatility of surface engineering as a way of optimizing electronic structure and catalytic performance of other related materials.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of the Taiwan Institute of Chemical Engineers
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2023
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IF 5.7
Mengbi Zhang,Yun Zhang,Hong Zhong,Liqing Li,Zhanfang Cao
Background Water electrolysis is one of the most competitive approaches to generate hydrogen. The economical stainless steel, which consists of transition metals such as Ni and Fe, has impressive catalytic tunability and tremendous application potential in hydrogen production . Methods In this work, a hydrothermal activation strategy is proposed for breaking the inert oxide layer of stainless steel and producing an active catalytic layer dominated by NiFe 2 O 4 spinel nanoparticles on the surface. The molybdate further complexes with the metal ions, disrupting the initial regular crystals of NiFe 2 O 4 and exposing more defects. At the same time, Mo atoms can further optimize the electronic structure, which is conducive to the kinetic process of the reaction. Significant Findings Consequently, the modified stainless steel requires only 270 mV to achieve a current density of 10 mA·cm −2 , much lower than 387 mV of bare 304 stainless steel (SS304). Moreover, the robust catalytic layer, evolved from the stainless steel's own elements, grows firmly on the surface and shows excellent stability in the test of 120 h. This work provides a novel strategy for developing low-cost stainless steel electrodes with superior performance and stability for oxygen evolution.
研究领域:
材料科学
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电化学
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能源转化
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
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IF 6.707
Jie Wang,Guicai Lv,Cheng Wang
Hydrogen production by electrochemical overall water splitting is considered as a clean and renewable approach for greener energy. However, the efficiency of water electrolysis suffers from the sluggish kinetics and high overpotential of OER. Although NiFe LDH is regarded as a promising OER catalyst, it faces the problem of poor conductivity, resulting in the limitations of HER performance. Herein, a hybrid nano-architecture of CoNiN@NiFe LDH as a bifunctional electrocatalyst for overall water splitting is fabricated via in-situ electrochemically assembling hierarchical NiFe LDH nanosheets on the surface of CoNiN. CoNiN@NiFe LDH shows excellent activities for OER with the overpotentials of 227 and 291 mV to deliver the current densities of 10 and 100 mA cm −2 , respectively. Moreover, an alkaline electrolyzer with CoNiN@NiFe LDH as anode and cathode requires a cell voltage of 1.63 V to achieve 10 mA cm −2 . In addition, the excellent stability with 100 h towards overall water splitting outperforms most transition metal-based bifunctional electrocatalysts. The superior performance is attributed to the abundant active sites, the strong electronic interaction, and the corresponding metal (oxy)hydroxides species generated by in situ surface reconstruction and phase transformation.
研究领域:
材料科学
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电化学
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能源转换
✓ 已验证
DOI
高影响因子
Batteries-Basel
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2022
·Vol. 8
·期 12
·259
·
IF 5.938
Kaixin Li,Zhanhua Dong,Zhe Lü
The development of robust and efficient electrocatalysts for use in fuel cells and metal–air batteries has garnered a great deal of interest due to the quest for clean and renewable energy sources. In this paper, a promising Co-doped Pr0.5Ba0.4Ca0.1Fe1-xCoxO3-δ(x = 0, 0.2, 0.4, 0.6, 0.8; denoted as PBCFC-x, x = 0, 2, 4, 6, 8) with enhanced durability and electrocatalytic ORR/OER activity for zinc–air battery cathode catalysts is presented. Particularly, PBCFC-6 exhibits the best bifunctional catalytic activity in alkaline media among several materials, according to research using the RDE. The zinc–air battery with PBCFC-6 as the cathode catalyst delivered the smallest discharge–charge voltage difference at the current density of 10 mA·cm−2and only increased by 0.031 V after 220 cycles (220 h), demonstrating its superior bifunctional catalytic activity and durability. The optimized electrochemical performance of both OER and ORR as well as stability in zinc–air batteries might result from the higher electrical conductivity, increasing concentration of adsorbed oxygen, and the greater proportion of Fe4+(t2g3eg1) with optimal electron occupancy, owing to the partial replacement of Fe with Co.Keywords:Pr0.5Ba0.4Ca0.1Fe1-xCoxO3-δ;rechargeable zinc–air batteries;ORR/OER;bifunctional catalyst
研究领域:
材料科学
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电化学
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能源技术
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
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IF 16.683
Pengfei Zhang,Yaoda Liu,Tingting Liang,Edison Huixiang Ang,Xu Zhang,Fei Ma,Zhengfei Dai
Efficient, inexpensive and stable electrocatalysts are challenging and desperately required in order to complement the water electrolysis of noble metal catalysts. Herein, a porous nitrogen-doped carbon wrapped Co-Mo 2 C dual Mott–Schottky heterostructure has been successfully fabricated by carbonization of Co-Zn bimetal metal-organic framework (MOF) for water electrolysis. The heterostructure is found to feature with Co and Mo 2 C nanoparticles uniformly encapsulated in the highly porous leaf-like N-doped carbon nanosheet matrix. Such a thin porous dual-Mott–Schottky configuration can afford abundant surface active sites and the boosted electron transfer to promote the water splitting. As for hydrogen/oxygen evolution reaction (HER/OER), it has demonstrated fast kinetics and low overpotentials of 92 mV (HER) and 338 mV (OER) at a current density of 10 mA cm −2 in 1 M KOH. Furthermore, the overall water splitting is stably delivered with a low cell voltage of 1.68 V at 10 mA cm -2 in 1 M KOH. Density function theory (DFT) calculations demonstrate that the interface correlation is favorable to water transfer by electron and speeds up adsorption and water dissociation. The work here opens up interesting possibilities for the rational design and innovation of MOF derived Mott–Schottky electrocatalysts for highly efficient water electrolysis.
研究领域:
材料科学
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电化学
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催化
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2017
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IF 6.395
Bo Xu,He Yang,Lincheng Yuan,Yiqiang Sun,Zhiming Chen,Cuncheng Li
Development of low-cost, highly active bifunctional catalyst for efficient overall water splitting based on earth-abundant metals is still a great challenging task. In this work, we report a NiFe-Se/C composite nanorod as efficient non-precious-metal electrochemical catalyst derived from direct selenylation of a mixed Ni/Fe metal-organic framework. The as-obtained catalyst requires low overpotential to drive 10 mA cm −2 for HER (160 mV) and OER (240 mV) in 1.0 M KOH, respectively, and its catalytic activity is maintained for at least 20 h. Moreover, water electrolysis using this catalyst achieves high water splitting current density of 10 mA cm −2 at cell voltage of 1.68 V.
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
Nanoscale
·
2021
·Vol. 13
·期 42
·17953-17960
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IF 7.79
Yuanyuan Wu,Junqiang Yin,Wei Jiang,Hongji Li,Chunbo Liu,Guangbo Che
Developing efficient and promising non-noble catalysts that can promote both the HER and OER in the same electrolyte is vital. Currently, these reported bifunctional catalysts show only moderate electrocatalytic water-splitting performance, which is much lower than expected. In addition, most of these promising nonprecious electrocatalysts work well only at small current densities (e.g. 10 mA cm−1), but at large current densities their stability and activity are far from satisfactory for practical applications. Herein, we have successfully constructed an urchin-like Ni3S2@Ni3B heterostructure electrocatalyst on Ni plates. The resulting material exhibits great catalytic activities for both the HER and OER, even at large current densities, reaching a current density of 1000 mA cm−l at relatively low applied overpotentials of 517 and 632 mV, respectively. The excellent catalytic performance of Ni3S2@Ni3B/NP is found to benefit from the effective integration of the unique surface structure and the interface electronic structure.
研究领域:
电化学
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材料科学
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催化
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
·
IF 9.965
Xinyu Chen,Jiexi Song,Yifei Xing,Yanqing Qin,Jianbin Lin,Xiao Qu,Bianjing Sun,Shiyu Du,Diwei Shi,Chuntao Chen,Dongping Sun
Designing transition metal-oxide-based bifunctional electrocatalysts with excellent activity and stability for OER/HER to achieve efficient water splitting is of great importance for renewable energy technologies. Herein, a highly efficient bifunctional catalysts with oxygen-rich vacancies of nickel-decorated RuO 2 (NiRuO 2−x ) prepared by a unique one-pot glucose-blowing approach were investigated. Remarkably, the NiRuO 2−x catalysts exhibited excellent HER and OER activity at 10 mA cm −2 in alkaline solution with only a minimum overpotential of 51 mV and 245 mV, respectively. Furthermore, the NiRuO 2−x overall water splitting exhibited an ultra-low voltage of 1.6 V to obtain 10 mA cm −2 and stability for more than 10 h. XPS measurement and theoretical calculations demonstrated that the introduction of Ni-dopant and oxygen vacancies make the d-band center to lie close to the Fermi energy level, the chemical bonds between the active site and the adsorbed oxygen intermediate state are enhanced, thereby lowering the reaction activation barriers of HER and OER. The assembly of solar-driven alkaline electrolyzers facilitate the application of the NiRuO 2−x bifunctional catalysts.
研究领域:
材料科学
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可再生能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Baoxin Ge,Pengyang Jiang,Caijin Huang,Biyi Chen,Xiaoqing Qiu
The effective activation of lattice oxygen can be triggered by modulating the metal–O covalency to activate the lattice oxygen oxidation mechanism (LOM) for the OER. In this work, we perform a systematic and comprehensive DFT screening across the entire lanthanide series to modulate the Ni–O covalency by constructing Ln–O–Ni orbital gradient coupling. We found that the Ni–O covalency can be maximized by the Gd(4f)–O(2p)–Ni(3d) gradient orbital coupling structure formed by Gd doping. Moreover, this structure effectively activates lattice oxygen for reaction participation by elevating the Ni 3d/O 2p band centers and promoting the formation of oxygen vacancies. Therefore, the OER mechanism changes from the adsorbate evolution mechanism to LOM, accelerating the generation of *OO intermediates, which, in turn, significantly lowers the reaction energy barrier. The as-prepared 2% Gd–NiO sample exhibited remarkable stability (180 h) and a low OER overpotential (235 mV@10 mA cm–2), outperforming most of the reported Ni-based alkaline OER electrocatalysts. Moreover, the Zn–air battery constructed with 2% Gd–NiO achieved an excellent energy conversion efficiency and cycling stability. This work provides a theoretical framework for the design of advanced LOM catalysts.
研究领域:
电催化
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材料科学
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能量转换
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计算化学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 7
·1847
·
IF 5.076
Yan Ma,Yujie Miao,Guomei Mu,Dunmin Lin,Chenggang Xu,Wen Zeng,Fengyu Xie
Great expectations have been held for the electrochemical splitting of water for producing hydrogen as a significant carbon-neutral technology aimed at solving the global energy crisis and greenhouse gas issues. However, the oxygen evolution reaction (OER) process must be energetically catalyzed over a long period at high output, leading to challenges for efficient and stable processing of electrodes for practical purposes. Here, we first prepared Fe-MOF nanosheet arrays on nickel foam via rare-earth erbium doping (Er0.4Fe-MOF/NF) and applied them as OER electrocatalysts. The Er0.4Fe-MOF/NF exhibited wonderful OER performance and could yield a 100 mA cm−2current density at an overpotential of 248 mV with outstanding long-term electrochemical durability for at least 100 h. At large current densities of 500 and 1000 mA cm−2, overpotentials of only 297 mV and 326 mV were achieved, respectively, revealing its potential in industrial applications. The enhancement was attributed to the synergistic effects of the Fe and Er sites, with Er playing a supporting role in the engineering of the electronic states of the Fe sites to endow them with enhanced OER activity. Such a strategy of engineering the OER activity of Fe-MOF via rare-earth ion doping paves a new avenue to design other MOF catalysts for industrial OER applications.Keywords:rare-earth doping;MOFs;large current;electronic structure
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
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