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Jin-Tao Ren Lei Wang Lei Chen Xin-Lian Song Qing-Hui Kong Hao-Yu Wang Zhong-Yong Yuan 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(5):2206196
Heterogeneous electrocatalysis typically depends on the surface electronic states of active sites. Modulating the surface charge state of an electrocatalysts can be employed to improve performance. Among all the investigated materials, nickel (Ni)-based catalysts are the only non-noble-metal-based alternatives for both hydrogen oxidation and evolution reactions (HOR and HER) in alkaline electrolyte, while their activities should be further improved because of the unfavorable hydrogen adsorption behavior. Hereto, Ni with exceptional HOR electrocatalytic performance by changing the d-band center by metal oxides interface coupling formed in situ is endowed. The resultant MoO2 coupled Ni heterostructures exhibit an apparent HOR activity, even approaching to that of commercial 20% Pt/C benchmark, but with better long-term stability in alkaline electrolyte. An exceptional HER performance is also achieved by the Ni-MoO2 heterostructures. The experiment results are rationalized by the theoretical calculations, which indicate that coupling MoO2 with Ni results in the downshift of d-band center of Ni, and thus weakens hydrogen adsorption and benefits for hydroxyl adsorption. This concept is further proved by other metal oxides (e.g., CeO2, V2O3, WO3, Cr2O3)-formed Ni-based heterostructures to engineer efficient hydrogen electrocatalysts. 相似文献
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Yu Zhou Joshua V. Pondick Jose Luis Silva John M. Woods David J. Hynek Grace Matthews Xin Shen Qingliang Feng Wen Liu Zhixing Lu Zhixiu Liang Barbara Brena Zhao Cai Min Wu Liying Jiao Shu Hu Hailiang Wang Carlos Moyses Araujo Judy J. Cha 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(19)
Using the MoS2‐WTe2 heterostructure as a model system combined with electrochemical microreactors and density function theory calculations, it is shown that heterostructured contacts enhance the hydrogen evolution reaction (HER) activity of monolayer MoS2. Two possible mechanisms are suggested to explain this enhancement: efficient charge injection through large‐area heterojunctions between MoS2 and WTe2 and effective screening of mirror charges due to the semimetallic nature of WTe2. The dielectric screening effect is proven minor, probed by measuring the HER activity of monolayer MoS2 on various support substrates with dielectric constants ranging from 4 to 300. Thus, the enhanced HER is attributed to the increased charge injection into MoS2 through large‐area heterojunctions. Based on this understanding, a MoS2/WTe2 hybrid catalyst is fabricated with an HER overpotential of ?140 mV at 10 mA cm?2, a Tafel slope of 40 mV dec?1, and long stability. These results demonstrate the importance of interfacial design in transition metal dichalcogenide HER catalysts. The microreactor platform presents an unambiguous approach to probe interfacial effects in various electrocatalytic reactions. 相似文献
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Dongdong Zhu Jinlong Liu Yongqiang Zhao Yao Zheng Shi‐Zhang Qiao 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(14)
2D metal–organic frameworks (MOFs) have been widely investigated for electrocatalysis because of their unique characteristics such as large specific surface area, tunable structures, and enhanced conductivity. However, most of the works are focused on oxygen evolution reaction. There are very limited numbers of reports on MOFs for hydrogen evolution reaction (HER), and generally these reported MOFs suffer from unsatisfactory HER activities. In this contribution, novel 2D Co‐BDC/MoS2 (BDC stands for 1,4‐benzenedicarboxylate, C8H4O4) hybrid nanosheets are synthesized via a facile sonication‐assisted solution strategy. The introduction of Co‐BDC induces a partial phase transfer from semiconducting 2H‐MoS2 to metallic 1T‐MoS2. Compared with 2H‐MoS2, 1T‐MoS2 can activate the inert basal plane to provide more catalytic active sites, which contributes significantly to improving HER activity. The well‐designed Co‐BDC/MoS2 interface is vital for alkaline HER, as Co‐BDC makes it possible to speed up the sluggish water dissociation (rate‐limiting step for alkaline HER), and modified MoS2 is favorable for the subsequent hydrogen generation step. As expected, the resultant 2D Co‐BDC/MoS2 hybrid nanosheets demonstrate remarkable catalytic activity and good stability toward alkaline HER, outperforming those of bare Co‐BDC, MoS2, and almost all the previously reported MOF‐based electrocatalysts. 相似文献
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Qian Liu Ziqian Xue Baoming Jia Qinglin Liu Kang Liu Yiyang Lin Min Liu Yinle Li Guangqin Li 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(32)
Hierarchical nanostructures with tailored component and architectures are attractive for energy‐related applications. Here, the delicate design and construction of hierarchical MoS2/MoP (H‐MoS2/MoP) nanorods for the hydrogen evolution reaction (HER) are demonstrated. This multiscale design rationally combines the compositional and structural advantages of MoS2/MoP heterojunction into a hierarchical architecture, which can modulate electronic structure of S, remarkably facilitating the electrocatalytic HER. Benefitting from their unique architecture and electronic structure, the H‐MoS2/MoP nanorods exhibit excellent performance for HER with ultralow overpotential of 92 mV at current density of 10 mA cm?2 in 1 m KOH and high stability. This work not only provides an efficient approach to constructing hierarchical heterojunctions, but also a multiscale strategy for all‐round regulation of the electronic structure and hierarchical morphology of nanomaterials for energy‐related applications. 相似文献
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Weiwei Yang Shuqing Zhang Qian Chen Chao Zhang Yi Wei Huaning Jiang Yunxiang Lin Mengting Zhao Qianqian He Xingguo Wang Yi Du Li Song Shubin Yang Anmin Nie Xiaolong Zou Yongji Gong 《Advanced materials (Deerfield Beach, Fla.)》2020,32(30):2001167
Lack of effective strategies to regulate the internal activity of MoS2 limits its practical application for hydrogen evolution reactions (HERs). Doping of heteroatoms without forming aggregation or an edge enrichment is still challenging, and its effect on the HER needs to be further explored. Herein, a two-step method is developed to obtain multi-metal-doped H-MoS2, which includes intercalation of the layered MoO3 precursor with a following sulfurization. Benefiting from the capability of the intercalation method to uniformly and simultaneously introduce different elements into the van der Waals gap, this method is universal to obtain multi-heteroatoms co-doped MoS2 without forming clusters, phase separation, and an edge enrichment. It is demonstrated that the doping of adjacent cobalt and palladium monomers on MoS2 greatly enhances the HER catalytic activity. The overpotential at 10 mA cm−2 and Tafel slope of Co and Pd co-doped MoS2 is found to be 49.3 mV and 43.2 mV dec−1, respectively, representing a superior acidic HER catalytic activity. This intercalation-assisted method also provides a new and general strategy to synthesize uniformly doped transition metal dichalcogenides for various applications. 相似文献
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Closest Packing Polymorphism Interfaced Metastable Transition Metal for Efficient Hydrogen Evolution
Xinyue Tan Shize Geng Yujin Ji Qi Shao Ting Zhu Pengtang Wang Youyong Li Xiaoqing Huang 《Advanced materials (Deerfield Beach, Fla.)》2020,32(40):2002857
Metastable materials are promising because of their catalytic properties, high-energy structure, and unique electronic environment. However, the unstable nature inherited from the metastability hinders further performance improvement and practical applications of these materials. Herein, this limitation is successfully addressed by constructing an in situ polymorphism interface (inf) between the metastable hexagonal-close-packed (hcp) phase and its stable counterpart (face-centered cubic, fcc) in cobalt–nickel (CoNi) alloy. Calculations reveal that the interfacial synergism derived from the hcp and fcc phases lowers the formation energy and enhances stability. Consequently, the optimized CoNi-inf exhibits an exceptionally low potential of 72 mV at 10 mA cm−2 and a Tafel slope of 57 mV dec−1 for the hydrogen evolution reaction (HER) in 1.0 m KOH. Furthermore, it is superior to most state-of-the-art non-noble-metal-based HER catalysts. No noticeable activity decay or structural changes are observed even over 14 h of catalysis. The computational simulation further rationalizes that the interface of CoNi-inf with a suitable d-band center provides uniform sites for hydrogen adsorption, leading to a distinguished HER catalytic activity. This work, therefore, presents a new route for designing metastable catalysts for potential energy conversion. 相似文献
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Pu Cheng liangliang Shi Wenqi Li Xiaorong Fang Dianliang Cao Yonggang Zhao Peng Cao Dequan Liu Deyan He 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(16):2206083
The notorious shuttle effect and sluggish conversion of polysulfides seriously hinder the practical application of Lithium-sulfur (Li-S) batteries. In this study, a novel architecture of MoS2/MoO3 heterostructure uniformly distributed on carbon nanotubes (MoS2/MoO3@CNT) is designed and introduced into Li-S batteries via decorating commercial separator to regulate the redox reactions of polysulfides. Systematic experiments and theoretical calculations showed that the heterostructure not only provides sufficient surface affinity to capture polysulfides and acts as an active catalyst to promote the conversion of polysulfides, but also the highly conductive CNT enables rapid electron/ion migration. As a result, Li-S batteries with the MoS2/MoO3@CNT-PP separator deliver an impressive reversible capacity (1015 mAh g−1 at 0.2 A g−1 after 100 cycles), excellent rate capacity (873 mAh g−1 at 5 A g−1), and low self-discharge capacity loss (94.6% capacity retention after 7 days of standing). Moreover, even at an elevated temperature of 70 °C, it still exhibits high-capacity retention (800 mAh g−1 at 1 A g−1 after 100 cycles). Encouragingly, when the sulfur load is increased to 8.7 mg cm−2, the high reversible areal capacity of 6.61 mAh cm−2 can be stably maintained after 100 cycles, indicating a high potential for practical application. 相似文献
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Yangyang Feng Ting Zhang Jiahui Zhang Hao Fan Cheng He Jiangxuan Song 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(33)
Metallic phase (1T) MoS2 has been regarded as an appealing material for hydrogen evolution reaction. In this work, a novel interface‐induced strategy is reported to achieve stable and high‐percentage 1T MoS2 through highly active 1T‐MoS2/CoS2 hetero‐nanostructure. Herein, a large number of heterointerfaces can be obtained by interlinked 1T‐MoS2 and CoS2 nanosheets in situ grown from the molybdate cobalt oxide nanorod under moderate conditions. Owing to the strong interaction between MoS2 and CoS2, high‐percentage of metallic‐phase (1T) MoS2 of 76.6% can be achieved, leading to high electroconductivity and abundant active sites compared to 2H MoS2. Furthermore, the interlinked MoS2 and CoS2 nanosheets can effectively disperse the nanosheets so as to enlarge the exposed active surface area. The near zero free energy of hydrogen adsorption at the heterointerface can also be achieved, indicating the fast kinetics and excellent catalytic activity induced by heterojunction. Therefore, when applied in hydrogen evolution reaction (HER), 1T‐MoS2/CoS2 heterostructure delivers low overpotential of 71 and 26 mV at the current density of 10 mA cm?2 with low Tafel slops of 60 and 43 mV dec?1, respectively in alkaline and acidic conditions. 相似文献
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Temperature‐Triggered Sulfur Vacancy Evolution in Monolayer MoS2/Graphene Heterostructures
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Mengxi Liu Jianping Shi Yuanchang Li Xiebo Zhou Donglin Ma Yue Qi Yanfeng Zhang Zhongfan Liu 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(40)
The existence of defects in 2D semiconductors has been predicted to generate unique physical properties and markedly influence their electronic and optoelectronic properties. In this work, it is found that the monolayer MoS2 prepared by chemical vapor deposition is nearly defect‐free after annealing under ultrahigh vacuum conditions at ≈400 K, as evidenced by scanning tunneling microscopy observations. However, after thermal annealing process at ≈900 K, the existence of dominant single sulfur vacancies and relatively rare vacancy chains (2S, 3S, and 4S) is convinced in monolayer MoS2 as‐grown on Au foils. Of particular significance is the revelation that the versatile vacancies can modulate the band structure of the monolayer MoS2, leading to a decrease of the bandgap and an obvious n‐doping effect. These results are confirmed by scanning tunneling spectroscopy data as well as first‐principles theoretical simulations of the related morphologies and the electronic properties of the various defect types. Briefly, this work should pave a novel route for defect engineering and hence the electronic property modulation of three‐atom‐thin 2D layered semiconductors. 相似文献
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二维层状二硫化钼(MoS_(2))是一种非常有前景的替代贵金属铂的电水解制氢催化剂。然而,MoS_(2)电子导电性较差,且在碱性氢析出反应(HER)中对水分子吸附/裂解的活化能垒较高,限制其在碱性电水解的应用。通过一步水热法将MoS_(2)纳米片均匀生长在三维导电碳布(CC)上,以有效提高电极导电性。随后在RuCl_(3)的乙醇溶液中通过溶剂热法可控制备超小Ru纳米颗粒负载MoS_(2)纳米片,形成CC@MoS_(2)/Ru异质结构。Ru的负载能有效促进水吸附/裂解反应,从而和MoS_(2)协同催化HER。采用X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)等方法对MoS_(2)/Ru进行结构和形貌表征。结果表明:MoS_(2)呈纳米片状交错生长在碳布上,并且超小Ru纳米颗粒(平均粒径2.5 nm)均匀负载在MoS_(2)纳米片上。将CC@MoS_(2)/Ru作为工作电极,石墨棒和Hg/HgO电极分别为对电极和参比电极进行碱性HER测试。在电流密度为-10 mA·cm^(-2)下的过电位仅为71.3 mV,Tafel斜率为104.8 mV·dec^(-1)。通过对其进行计时电位滴定法稳定性测试,发现在恒电流密度-10 mA·cm^(-2)下能够维持至少35 h而没有明显性能衰减。 相似文献
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Wencui Zhang Xiaobin Liao Xuelei Pan Mengyu Yan Yanxi Li Xiaocong Tian Yan Zhao Lin Xu Liqiang Mai 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(31)
In the hydrogen evolution reaction (HER), energy‐level matching is a prerequisite for excellent electrocatalytic activity. Conventional strategies such as chemical doping and the incorporation of defects underscore the complicated process of controlling the doping species and the defect concentration, which obstructs the understanding of the function of band structure in HER catalysis. Accordingly, 2H‐MoS2 and 1T‐MoS2 are used to create electrocatalytic nanodevices to address the function of band structure in HER catalysis. Interestingly, it is found that the 2H‐MoS2 with modulated Fermi level under the application of a vertical electric field exhibits excellent electrocatalytic activity (as evidenced by an overpotential of 74 mV at 10 mA cm?2 and a Tafel slope of 99 mV per decade), which is superior to 1T‐MoS2. This unexpected excellent HER performance is ascribed to the fact that electrons are injected into the conduction band under the condition of back‐gate voltage, which leads to the increased Fermi level of 2H‐MoS2 and a shorter Debye screen length. Hence, the required energy to drive electrons from the electrocatalyst surface to reactant will decrease, which activates the 2H‐MoS2 thermodynamically. 相似文献
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P‐GaSe/N‐MoS2 Vertical Heterostructures Synthesized by van der Waals Epitaxy for Photoresponse Modulation
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Nan Zhou Renyan Wang Xing Zhou Hongyue Song Xing Xiong Yao Ding Jingtao Lü Lin Gan Tianyou Zhai 《Small (Weinheim an der Bergstrasse, Germany)》2018,14(7)
The important role of p–n junction in modulation of the optoelectronic properties of semiconductors is widely cognized. In this work, for the first time the synthesis of p‐GaSe/n‐MoS2 heterostructures via van der Waals expitaxial growth is reported, although a considerable lattice mismatching of ≈18% exists. According to the simulation, a significant type II p–n junction barrier located at the interface is expected to be formed, which can modulate optoelectronic properties of MoS2 effectively. It is intriguing to reveal that the presence of GaSe can result in obvious Raman and photoluminescence (PL) shift of MoS2 compared to that of pristine one, more interestingly, for PL peak shift, the effect of GaSe‐induced tensile strain on MoS2 has overcome the p‐doping effect of GaSe, evidencing the strong interlayer coupling between GaSe and MoS2. As a result, the photoresponse rate of heterostructures is improved by almost three orders of magnitude compared with that of pristine MoS2. 相似文献
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Plasmon‐Enhanced Photoelectrical Hydrogen Evolution on Monolayer MoS2 Decorated Cu1.75S‐Au Nanocrystals
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Jiabin Cui Rui Jiang Wenli Lu Suying Xu Leyu Wang 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(8)
Hydrogen production from water splitting through an efficient photoelectrochemical route requires photoinduced electron transfer from light harvesters to efficient electrocatalysts. Here, the plasmon‐enhanced photoelectrical nanocatalysts (NCs) have been successfully developed by coating a monolayer MoS2 on the Cu1.75S‐Au hetero‐nanoparticle for hydrogen evolution reaction (HER). The plasmonic NCs dramatically improve the HER, leading to 29.5‐fold increase of current under 650 nm excitation (1.0 W cm?2). These NCs generate an exceptionally high current density of 200 mA cm?2 at overpotential of 182.8 mV with a Tafel slope of 39 mV per decade and excellent stability, which is better than or comparable to the Pt‐free catalysts with carbon rod as counter electrode. The enhanced HER performance can be attributed to the significantly improved broad light absorption (400–3000 nm), more efficient charge separation and abundant active edge sites of monolayer MoS2. The studies may provide a facile strategy for the fabrication of efficient plasmon‐enhanced photoelectrical NCs for HER. 相似文献
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Xinyue Li Dian Luo Fan Jiang Kuanjian Zhang Shaoxia Wang Shifeng Li Qingqing Zha Yucheng Huang Yonghong Ni 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(28):2301850
Designing excellent electrocatalysts for the hydrogen evolution reaction (HER) is extremely significant in producing clean and sustainable hydrogen fuel. Herein, a rational strategy is developed to fabricate a promising electrocatalyst by introducing atomically dispersed Ru into a cobalt-based metal-organic framework (MOF), Co-BPDC (Co(bpdc)(H2O)2, BPDC: 4,4'-Biphenyldicarboxylic acid). The obtained CoRu-BPDC nanosheet arrays exhibit remarkable HER performance with an overpotential of 37 mV at a current density of 10 mA cm−2 in alkaline media, which is superior to most of the MOF-based electrocatalysts and comparable to the commercial Pt/C. Synchrotron radiation-based X-ray absorption fine structure (XAFS) spectroscopy studies verify that the isolated Ru atoms are dispersed in Co-BPDC nanosheets with the formation of five-coordinated Ru-O5 species. XAFS spectroscopy combined with density functional theory (DFT) calculations unravels that atomically dispersed Ru can modulate the electronic structure of the as-obtained Co-BPDC, contributing to the optimization of binding strength for H* and the enhancement of HER performance. This work opens a new avenue to rationally design highly-active single-atom modified MOF-based HER electrocatalysts via modulating electronic structures of MOF. 相似文献
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Zhe Li Yi Feng Yu-Lin Liang Chuan-Qi Cheng Cun-Ku Dong Hui Liu Xi-Wen Du 《Advanced materials (Deerfield Beach, Fla.)》2020,32(25):1908521
Water electrolysis in alkaline electrolyte is an attractive way toward clean hydrogen energy via the hydrogen evolution reaction (HER), whereas the sluggish water dissociation impedes the following hydrogen evolution. Noble metal oxides possess promising capability for catalyzing water dissociation and hydrogen evolution; however, they are never utilized for the HER due to the instability under the reductive potential. Here it is shown that compressive strain can stabilize RhO2 clusters and promote their catalytic activity. To this end, a strawberry-like structure with RhO2 clusters embedded in the surface layer of Rh nanoparticles is engineered, in which the incompatibility between the oxide cluster and the metal substrate causes intensive compressive strain. As such, RhO2 clusters remain stable at a reduction potential up to −0.3 V versus reversible hydrogen electrode and present an alkaline HER activity superior to commercial Pt/C. 相似文献
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Jinlong Liu Zhenyu Wang Jun Li Lujie Cao Zhouguang Lu Dongdong Zhu 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(4)
Oxygen and phosphorus dual‐doped MoS2 nanosheets (O,P‐MoS2) with porous structure and continuous conductive network are fabricated using a one‐pot NaH2PO2‐assisted hydrothermal approach. By simply changing the precursor solution, the chemical composition and resulting structure can be effectively controlled to obtain desired properties toward the hydrogen evolution reaction (HER). Thanks to the beneficial structure and strong synergistic effects between the incorporated oxygen and phosphorus, the optimal O,P‐MoS2 exhibit superior electrocatalytic performances compared with those of oxygen single‐doped MoS2 nanosheets (O‐MoS2). Specifically, a low HER onset overpotential of 150 mV with a small Tafel slope of 53 mV dec?1, excellent conductivity, and long‐term durability are achieved by the structural engineering of MoS2 via O and P co‐doping, making it an efficient HER electrocatalyst for water electrocatalysis. This work provides an alternative strategy to manipulate transition metal dichalcogenides as advanced materials for electrocatalytic and related energy applications. 相似文献
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Tao Ling Tong Zhang Binghui Ge Lili Han Lirong Zheng Feng Lin Zhengrui Xu Wen‐Bin Hu Xi‐Wen Du Kenneth Davey Shi‐Zhang Qiao 《Advanced materials (Deerfield Beach, Fla.)》2019,31(16)
The practical scale‐up of renewable energy technologies will require catalysts that are more efficient and durable than present ones. This is, however, a formidable challenge that will demand a new capability to tailor the electronic structure. Here, an original electronic structure tailoring of CoO by Ni and Zn dual doping is reported. This changes it from an inert material into one that is highly active for the hydrogen evolution reaction (HER). Based on combined density functional theory calculations and cutting‐edge characterizations, it is shown that dual Ni and Zn doping is responsible for a highly significant increase in HER activity of the host oxide. That is, the Ni dopants cluster around surface oxygen vacancy of the host oxide and provide an ideal electronic surface structure for hydrogen intermediate binding, while the Zn dopants distribute inside the host oxide and modulate the bulk electronic structure to boost electrical conduction. As a result, the dual‐doped Ni, Zn CoO nanorods achieve current densities of 10 and 20 mA cm?2 at overpotentials of, respectively, 53 and 79 mV. This outperforms reported state‐of‐the‐art metal oxide, metal oxide/metal, metal sulfide, and metal phosphide catalysts. 相似文献