MATERIALS CHEMISTRY AND PHYSICS
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2021
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IF 4.094
Yanxia Zeng,Xiashi Zhu,Yuheng Zhang,Songqing Chen,Wei Zhang,Lei Wang
Electrochemical water electrolysis is an efficient important way to produce hydrogen. In this work, durable and low-cost Co 2 P/CoP was synthesized by a facile one-step calcination reaction. Subsequently, Co 2 P/CoP was characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microcopy (TEM), X-ray photoelectron spectra (XPS). To evaluate the electrocatalytic hydrogen evolution activity, Co 2 P/CoP was measured by electrochemical tests. Co 2 P/CoP exhibited excellent HER performance with a small overpotential of 196 mV at a current density of 10 mA cm −2 and a smaller Tafel slope of 53 mV dec −1 in alkaline media. Moreover, Co 2 P/CoP exhibited superior stability with long-term operation of 24 h.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2022
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IF 9.965
Dingzhou Xiang,Xuqiang Hao,Zhiliang Jin
Amorphous/crystalline heterostructures show excellent potential in the hydrogen evolution reaction (HER) as they can significantly facilitate surface adsorption and redox reactions. Herein, a unique amorphous Co 2 P/crystalline CoP quantum dots (Co 2 P/CoP QDs) Type-II surface heterojunction was derived from amorphous Co 3 O 4 QDs via phosphorization. The intimate contact between Co 2 P QDs and CoP QDs was conducive to charge transfer, thereby promoting surface reaction kinetics. The unique structure and properties were beneficial to providing more active sites and controlling the electronic structures thus making amorphous/crystalline composites show superior photocatalytic hydrogen (H 2 ) production performance. Additionally, the amorphous Co 2 P QDs had a plethora of unsaturated bonds and abundant defects; the disordered structure led to increased active sites that promoted surface reaction kinetics. Due to the synergistic effect of the quantum confinement of QDs and the surface heterojunction, the charge transfer efficiency of Co 2 P/CoP QDs was extremely high, and high H 2 evolution activity and photostability were achieved. The maximum H 2 generation rate over the Co 2 P/CoP QDs composite reached 11.88 mmol h −1 g −1 with an apparent quantum efficiency (AQE) of 3.88 % at 420 nm, which is roughly 20-times that of the pure Co 3 O 4 QDs. In addition, high photostability was realized; even the photocatalyst that stood for a week reached initial photoactivity. This work offers a novel idea for reasonably establishing amorphous/crystalline photocatalysts to achieve efficient H 2 evolution.
研究领域:
材料科学
·
能源化学
✓ 已验证
DOI
高影响因子
Materials
·
2023
·Vol. 17
·期 1
·87
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IF 3.4
Ying Lei,Feng Lin,Nengyu Hong,Jian Zhang,Yulin Wang,Haijie Ben,Jianguang Li,Liyong Ding,Liang Lv
Noble metal-free electrocatalysts have received widespread attention in a hydrogen evolution reaction (HER) due to the importance of renewable energy development. Herein, a Co2P/CoP heterojunction embedded on an N-doped carbon (Co2P/CoP/NC) electrocatalyst was prepared via an in situ pyrolysis method. The as-prepared electrocatalyst exhibited efficient electrocatalytic activity for HER in an acidic solution. The Co2P/CoP/NC catalyst displayed an overpotential of 184 mV at 10 mA cm−2and a low Tafel slope of 82 mV dec−1, which could be attributed to the tight Co2P/CoP heterojunction and the synergetic effect of Co2P/CoP and N-doped carbon. In addition, the electrochemical active surface area of Co2P/CoP/NC was 75.2 m2g−1, which indicated that more active regions can be applied for the HER process. This report may pave a new way for the design of efficient and low-cost N-doped-carbon-supported 3d transition metal phosphide electrocatalysts.
研究领域:
材料科学
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电化学
·
可再生能源
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2023
·
IF 6.2
Shao-Bo Guo,Wei-Bin Zhang,Ze-Qin Yang,Shan-Shan Chai,Xian-Li Zhang,Xia Zhou,Xiong-Wei Han,Jianping Long
It has become a consensus to study transition metal phosphides with abundant earth reserves and good electrochemical properties as electrode materials for supercapacitors . Among them, cobalt phosphide is particularly attractive because of its good electrical conductivity and theoretical specific capacity. Therefore, cobalt phosphide composites were prepared by hydrothermal reaction and phosphating reaction in this paper. Due to the synergistic effect of different components and the interfacial effect between the components, the ion transport and charge transfer kinetics of the prepared Co/Co 2 P/CoP electrode are both improved, which exhibits excellent electrochemical performance. At the current density of 1 A g −1 , the prepared Co/Co 2 P/CoP electrode material has a specific capacitance of 193.3 mA h g −1 , after 6000 cycles of charge and discharge at the current density of 2 A g −1 , the specific capacitance maintains at 80 %. An asymmetric supercapacitor was assembled with the prepared material as the positive electrode and activated carbon as the negative electrode, which can provide an energy density of 37.87 W h kg −1 at a power density of 799.6 W kg −1 . At the current density of 1 A g −1 , the assembled supercapacitor can maintain 80 % of the initial specific capacitance after 5000 cycles. This provides ideas for future research on this type of energy storage materials .
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 CATALYSIS
·
2020
·
IF 7.888
Guoju Huang,Wanli Liang,Yinlong Wu,Jiawang Li,Yan Qi Jin,Hongbin Zeng,Hao Zhang,Fangyan Xie,Jian Chen,Nan Wang,Yanshuo Jin,Hui Meng
Due to the rapid development of alkaline polymer electrolyte fuel cells and water splitting, it is becoming increasingly urgent to develop non-precious metal electrocatalysts for the hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) in alkaline medium. Herein, Co 2 P/CoP hybrid is synthesized from cobalt carbonate hydroxide (CoCH) precursor, and further evaluated for the electrocatalytic HOR and HER in alkaline electrolytes. Specifically, benefiting from the reasonable hybrid structure that integrate suitable hydrogen adsorption energy of CoP and excellent conductivity of Co 2 P, Co 2 P/CoP hybrid exhibits excellent catalytic activities. The Co 2 P/CoP@NF hybrid has impressive HER activity, with a current density of −10 mA cm −2 at the overpotentials of −61 mV and the Tafel slope of 55.1 mV dec −1 , which can compete with recently reported transition metal phosphides and cobalt-based catalysts. In addition, the exchange current density of Co 2 P/CoP@NF hybrid is ~ 0.82 mA cm −2 for HOR, which is close to commercial Pt/C catalyst (~1.14 mA cm −2 ).
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2025
·
IF 6.4
Chongxi Zhang,Fengting Li,Dong Wu,Qingmeng Guo,Zhanning Liu,Zhikun Wang,Zixi Kang,Lili Fan,Daofeng Sun
Integration of cobalt phosphides (Co2P and CoP) in a carbon matrix shows great promise for developing high-performance catalysts for water electrolysis. Nevertheless, the controlled synthesis of these two phases with an effective interface, uniform dispersion, and a simplified synthesis process is still challenging. Herein, we proposed a strategy that involves pre-construction of the Co/CoO@C heterostructure followed by post-conversion by phosphorization to achieve the precise synthesis of the Co2P/CoP@C heterostructure, which was realized by utilizing a MOF as the self-sacrificial template. The oxygen-coordinated MOF that shows advantages in building the Co/CoO heterostructure was employed in this work and grown into a high-quality membrane via cathodic electrodeposition on the graphite substrate (Gss). The obtained catalyst (Gss-Co2P/CoP@C-800) requires 146 and 365 mV overpotentials to achieve a current density of 100 mA cm−2 for the HER and OER, respectively, and 1.54 V to achieve a current density of 10 mA cm−2 for water electrolysis. Beyond the significantly enhanced conductivity that originates from the robust interaction between the MOF and Gss, the establishment of an effective Co2P/CoP interface also plays a pivotal role in contributing to the high performance of Gss-Co2P/CoP@C-800. As revealed by density functional theory (DFT) calculations, the unique d-orbital electron distribution of Co2P/CoP and the enhanced state density near the Fermi level facilitate its efficient electron transport and render the Co2P/CoP heterostructure region a crucial active site for water electrolysis. This study will provide new insights into the rational design and construction of heterostructures based on MOFs for efficient and green energy conversions.
研究领域:
材料科学
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电化学
·
催化
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Xinli Yi,Lizhu Song,Shuxin Ouyang,Ning Wang,Huayu Chen,Jianbo Wang,Jun Lv,Jinhua Ye
The development of electrocatalysts for efficient water splitting is a pivotal and challenging task. Transition-metal phosphides (TMPs) have been known as one of the most promising candidates for the efficient hydrogen evolution reaction (HER) due to their favorable intrinsic reactivity. However, structural engineering related to the gas bubbles evolution and tiny regulation of components concerned with the electronic structure remained as a significant challenge that requires further optimization. Herein, the nanoarrays (NAs) composed of ultrasmall Co2P and CoP nanoparticle-embedded N-doped carbon matrix (Co2P&CoP@N–C) are prepared and demonstrated an overpotential of 62.8 ± 4.7 mV at 10 mA cm–2 in 1.0 M KOH. The nanoarray-structured electrocatalyst revealed the superaerophobicity and facilitates the detachment of the in situ formed hydrogen gas bubbles, ensuring abundant catalytic sites and electrode–electrolyte interface for the mass transfer process. The amount of P doping modulated the local electron density around Co and P atoms, which attains a favorable compromise to afford sufficient electrons for the electrocatalysis and inhibit the negative influence of H2 desorption. Significantly, the lowered overpotential induced by the electrocatalyst surface architecture is much stronger than that of the component content and promotes the electrocatalytic activity.
研究领域:
材料科学
·
能源工程
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Xu Yu,Xinyu Wang,Pinyi He,Guohui Yang,Lijing Gao,Fu Qin,Yongkang Yao,Jianliang Bai,Lili Ren
The interfacial electron modulation of electrocatalysts is a useful technique for promoting catalyst performance for the water-related dissociation reactions. Herein, a high-efficient Fe-doped allotropic Co 2 P/CoP heterojunction nanoparticles embedded in N, P co-doped carbon matrix was constructed. The intense electrical interfacial contacts between the allotropic heterojunction optimized the reaction kinetics by boosting efficient charged active centers, regulating the intermediate adsorption/desorption. The incorporation of Fe atoms further enhancing the heterointerface contact between CoP and Co 2 P by providing favorable electronic properties and special coordination environment, causing the interfacial coupling enhancement. Therefore, Fe-Co 2 P/CoP possesses outstanding performance in both hydrogen evolution reaction and oxygen evolution reaction, with small overpotentials of 174 mV and 286 mV at 10 mA·cm −2 in alkaline medium, respectively. And only 1.71 V battery voltage is needed for the Fe-Co 2 P/CoP (+, −) cell device with satisfactory durability. This finding provides valuable insights into the engineering of electronic structures of well-designed metal phosphides for water electrolysis.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）