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1.
Liling Liao Jingying Sun Dongyang Li Fang Yu Yijun Zhu Yi Yang Jinjian Wang Weichang Zhou Dongsheng Tang Shuo Chen Haiqing Zhou 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(13)
Developing efficient non‐noble and earth‐abundant hydrogen‐evolving electrocatalysts is highly desirable for improving the energy efficiency of water splitting in base. Molybdenum disulfide (MoS2) is a promising candidate, but its catalytic activity is kinetically retarded in alkaline media due to the unfavorable water adsorption and dissociation feature. A heterogeneous electrocatalyst is reported that is constructed by selenium‐doped MoS2 (Se‐MoS2) particles on 3D interwoven cobalt diselenide (CoSe2) nanowire arrays that drives the hydrogen evolution reaction (HER) with fast reaction kinetics in base. The resultant Se‐MoS2/CoSe2 hybrid exhibits an outstanding catalytic HER performance with extremely low overpotentials of 30 and 93 mV at 10 and 100 mA cm–2 in base, respectively, which outperforms most of the inexpensive alkaline HER catalysts, and is among the best alkaline catalytic activity reported so far. Moreover, this hybrid catalyst shows exceptional catalytic performance with very low overpotentials of 84 and 95 mV at 10 mA cm–2 in acidic and neutral electrolytes, respectively, implying robust pH universality of this hybrid catalyst. This work may provide new inspirations for the development of high‐performance MoS2‐based HER electrocatalysts in unfavorable basic media for promising catalytic applications. 相似文献
2.
Using electrochemical water splitting to produce hydrogen is still a grand challenge due to the lack of economical and efficient Pt‐free catalysts. Herein, a single‐atom Ru supported on MoS2 (SA‐Ru‐MoS2) electrocatalyst for the hydrogen evolution reaction (HER) is reported. Results indicate that single‐atom Ru doping induces phase transition of MoS2 and generation of S vacancies, which significantly improve the performance of inert 2D MoS2 for HER. In particular, the SA‐Ru‐MoS2 electrocatalyst exhibits a low overpotential of 76 mV at 10 mA cm−2 in alkaline media, which is superior to most electrocatalysts previously reported in the literature. Combining experimental results with density functional theory (DFT) calculations, it is further revealed that the origin of high HER activity is mainly attributed to the synergy effects of single‐atom Ru doping and S vacancies and phase transition of local structure of MoS2, which efficiently tailors the electronic structure of SA‐Ru‐MoS2 and extremely reduces the energy barrier of the Volmer step and the adsorption/desorption of H* intermediate step. In short, this work provides a single‐atom doping strategy to transfer the inert MoS2 into the highly efficient electrocatalysts. 相似文献
3.
Minki Baek Guan‐Woo Kim Taiho Park Kijung Yong 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(49)
Complementary water splitting electrocatalysts used simultaneously in the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) can simplify water splitting systems. Herein, earth‐abundant NiMoFe (NMF) and phosphorized NiMoFeP (NMFP) are synthesized as complementary overall water splitting (OWS) catalysts. First, NMF is tested as both the HER and OER promoter, which exhibits low overpotentials of 68 (HER) and 337 mV (OER). A quaternary NMFP is then prepared by simple phosphorization of NMF, which shows a much lower OER overpotential of 286 mV. The enhanced OER activity is attributed to the unique surface/core structure of NMFP. The surface phosphate acts as a proton transport mediator and expedites the rate‐determining step. With the application of OER potential, the NMFP surface is composed of Ni(OH)2 and FeOOH, active sites for OER, but the inner core consists of Ni, Mo, and Fe metals, serving as a conductive electron pathway. OWS with NMF‐NMFP requires an applied voltage of 1.452 V to generate 10 mA cm?2, which is one of the lowest values among OWS results with transition‐metal‐based electrocatalysts. Furthermore, the catalysts are combined with tandem perovskite solar cells for photovoltaic (PV)‐electrolysis, producing a high solar‐to‐hydrogen (STH) conversion efficiency of 12.3%. 相似文献
4.
Jun Yang Yifan Cao Shuyu Zhang Qingwen Shi Siyu Chen Shengcai Zhu Yunsong Li Jianfeng Huang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(29):2207295
Tungsten oxide (WO3) is an appealing electrocatalyst for the hydrogen evolution reaction (HER) owing to its cost-effectiveness and structural adjustability. However, the WO3 electrocatalyst displays undesirable intrinsic activity for the HER, which originates from the strong hydrogen adsorption energy. Herein, for effective defect engineering, a hydrogen atom inserted into the interstitial lattice site of tungsten oxide (H0.23WO3) is proposed to enhance the catalytic activity by adjusting the surface electronic structure and weakening the hydrogen adsorption energy. Experimentally, the H0.23WO3 electrocatalyst is successfully prepared on reduced graphene oxide. It exhibits significantly improved electrocatalytic activity for HER, with a low overpotential of 33 mV to drive a current density of 10 mA cm−2 and ultra-long catalytic stability at high-throughput hydrogen output (200 000 s, 90 mA cm−2) in acidic media. Theoretically, density functional theory calculations indicate that strong interactions between interstitial hydrogen and lattice oxygen lower the electron density distributions of the d-orbitals of the active tungsten (W) centers to weaken the adsorption of hydrogen intermediates on W-sites, thereby sufficiently promoting fast desorption from the catalyst surface. This work enriches defect engineering to modulate the electron structure and provides a new pathway for the rational design of efficient catalysts for HER. 相似文献
5.
Rahele Meshkian Martin Dahlqvist Jun Lu Björn Wickman Joseph Halim Jimmy Thörnberg Quanzheng Tao Shixuan Li Saad Intikhab Joshua Snyder Michel W. Barsoum Melike Yildizhan Justinas Palisaitis Lars Hultman Per O. Å. Persson Johanna Rosen 《Advanced materials (Deerfield Beach, Fla.)》2018,30(21)
Structural design on the atomic level can provide novel chemistries of hybrid MAX phases and their MXenes. Herein, density functional theory is used to predict phase stability of quaternary i‐MAX phases with in‐plane chemical order and a general chemistry (W2/3M21/3)2AC, where M2 = Sc, Y (W), and A = Al, Si, Ga, Ge, In, and Sn. Of over 18 compositions probed, only two—with a monoclinic C2/c structure—are predicted to be stable: (W2/3Sc1/3)2AlC and (W2/3Y1/3)2AlC and indeed found to exist. Selectively etching the Al and Sc/Y atoms from these 3D laminates results in W1.33C‐based MXene sheets with ordered metal divacancies. Using electrochemical experiments, this MXene is shown to be a new, promising catalyst for the hydrogen evolution reaction. The addition of yet one more element, W, to the stable of M elements known to form MAX phases, and the synthesis of a pure W‐based MXene establishes that the etching of i‐MAX phases is a fruitful path for creating new MXene chemistries that has hitherto been not possible, a fact that perforce increases the potential of tuning MXene properties for myriad applications. 相似文献
6.
In the near future, sustainable energy conversion and storage will largely depend on the electrochemical splitting of water into hydrogen and oxygen. Perceiving this, countless research works focussing on the fundamentals of electrocatalysis of water splitting and on performance improvements are being reported everyday around the globe. Electrocatalysts of high activity, selectivity, and stability are anticipated as they directly determine energy‐ and cost efficiency of water electrolyzers. Amorphous electrocatalysts with several advantages over crystalline counterparts are found to perform better in electrocatalytic water splitting. There are plenty of studies witnessing performance enhancements in electrocatalysis of water splitting while employing amorphous materials as catalysts. The harmony between the flexibility of amorphous electrocatalysts and electrocatalysis of water splitting (both the oxygen evolution reaction [OER] and the hydrogen evolution reaction [HER]) is one of the untold and unsummarized stories in the field of electrocatalytic water splitting. This Review is devoted to comprehensively discussing the upsurge of amorphous electrocatalysts in electrochemical water splitting. In addition to that, the basics of electrocatalysis of water splitting are also elaborately introduced and the characteristics of a good electrocatalyst for OER and HER are discussed. 相似文献
7.
Xuesi Wang Anthony Vasileff Yan Jiao Yao Zheng Shi‐Zhang Qiao 《Advanced materials (Deerfield Beach, Fla.)》2019,31(13)
Since first being reported as possible electrocatalysts to substitute platinum for the oxygen reduction reaction (ORR), carbon‐based metal‐free nanomaterials have been considered a class of promising low‐cost materials for clean and sustainable energy‐conversion reactions. However, beyond the ORR, the development of carbon‐based catalysts for other electrocatalytic reactions is still limited. More importantly, the intrinsic activity of most carbon‐based metal‐free catalysts is inadequate compared to their metal‐based counterparts. To address this challenge, more design strategies are needed in order to improve the overall performance of carbon‐based materials. Herein, using water splitting as an example, some state‐of‐the‐art strategies in promoting carbon‐based nanomaterials are summarized, including graphene, carbon nanotubes, and graphitic‐carbon nitride, as highly active electrocatalysts for hydrogen evolution and oxygen evolution reactions. It is shown that by rationally tuning the electronic and/or physical structure of the carbon nanomaterials, adsorption of reaction intermediates is optimized, consequently improving the apparent electrocatalytic performance. These strategies may facilitate the development in this area and lead to the discovery of advanced carbon‐based nanomaterials for various applications in energy‐conversion processes. 相似文献
8.
Converting solar energy into hydrogen via photoelectrochemical (PEC) water splitting is one of the most promising approaches for a sustainable energy supply. Highly active, cost‐effective, and robust photoelectrodes are undoubtedly crucial for the PEC technology. To achieve this goal, transition‐metal‐based electrocatalysts have been widely used as cocatalysts to improve the performance of PEC cells for water splitting. Herein, this Review summarizes the recent progresses of the design, synthesis, and application of transition‐metal‐based electrocatalysts as cocatalysts for PEC water splitting. Mo, Ni, Co‐based electrocatalysts for the hydrogen evolution reaction (HER) and Co, Ni, Fe‐based electrocatalysts for the oxygen evolution reaction (OER) are emphasized as cocatalysts for efficient PEC HER and OER, respectively. Particularly, some most efficient and robust photoelectrode systems with record photocurrent density or durability for the half reactions of HER and OER are highlighted and discussed. In addition, the self‐biased PEC devices with high solar‐to‐hydrogen efficiency based on earth‐abundant materials are also addressed. Finally, this Review is concluded with a summary and remarks on some challenges and opportunities for the further development of transition‐metal‐based electrocatalysts as cocatalysts for PEC water splitting. 相似文献
9.
Shengqi Ding Liang Wu Fang Zhang Xianxia Yuan 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(27):2300602
Introducing heteroatom into catalyst lattice to modulate its intrinsic electronic structure is an efficient strategy to improve the electrocatalytic performance in Li–O2 batteries. Herein, Cu-doped CoS2 (Cu–CoS2) nanoparticles are fabricated by a solvothermal method and evaluated as promising cathode catalysts for Li–O2 batteries. Based on physicochemical analysis as well as density functional theory calculations, it is revealed that doping Cu heteroatom in CoS2 lattice can increase the covalency of the Co S bond with more electron transfer from Co 3d to S 3p orbitals, thereby resulting in less electron transfer from Co 3d to O 2p orbitals of Li–O species, which can weaken the adsorption strength toward Li–O intermediates, decrease the reaction barrier, and thus improve the catalytic performance in Li–O2 batteries. As a result, the battery using Cu–CoS2 nanoparticles in the cathode exhibits superior kinetics, reversibility, capacity, and cycling performance, as compared to the battery based on CoS2 catalyst. This work provides an atomic-level insight into the rational design of transition-metal dichalcogenide catalysts via regulating the electronic structure for high-performance Li–O2 batteries. 相似文献
10.
Hui Li Qi Li Peng Wen Trey B. Williams Shiba Adhikari Chaochao Dun Chang Lu Dominique Itanze Lin Jiang David L. Carroll George L. Donati Pamela M. Lundin Yejun Qiu Scott M. Geyer 《Advanced materials (Deerfield Beach, Fla.)》2018,30(9)
Highly efficient and stable electrocatalysts, particularly those that are capable of multifunctionality in the same electrolyte, are in high demand for the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). In this work, highly monodisperse CoP and Co2P nanocrystals (NCs) are synthesized using a robust solution‐phase method. The highly exposed (211) crystal plane and abundant surface phosphide atoms make the CoP NCs efficient catalysts toward ORR and HER, while metal‐rich Co2P NCs show higher OER performance owing to easier formation of plentiful Co2P@COOH heterojunctions. Density functional theory calculation results indicate that the desorption of OH* from cobalt sites is the rate‐limiting step for both CoP and Co2P in ORR and that the high content of phosphide can lower the reaction barrier. A water electrolyzer constructed with a CoP NC cathode and a Co2P NC anode can achieve a current density of 10 mA cm?2 at 1.56 V, comparable even to the noble metal‐based Pt/C and RuO2/C pair. Furthermore, the CoP NCs are employed as an air cathode in a primary zinc–air battery, exhibiting a high power density of 62 mW cm?2 and good stability. 相似文献
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12.
Yanshuo Jin Haotian Wang Junjie Li Xin Yue Yujie Han Pei Kang Shen Yi Cui 《Advanced materials (Deerfield Beach, Fla.)》2016,28(19):3785-3790
13.
Recent studies show that the Pt electrode can be slowly dissolved into the acidic media and regenerate on the working electrode along with the long‐time hydrogen evolution reaction (HER) test. However, to date, the relationship between the Pt deposition and the intrinsic properties of the working electrode remains elusive. Herein, for the first time, the edge selectivity of in situ electrochemical Pt deposition on layered 2H‐WS2 nanosheets, whose edge surface with rich dangling bonds is chemically active to regulate their properties, especially the interfacial reaction occurring between the electrode surface and the adjacent thin layer of the solution, is theoretically elucidated and experimentally verified by controlling the cathode polarization test using Pt wire as the counter electrode in H2SO4 solution. It is revealed that the layered WS2 nanosheets with rich exposed edges show much stronger interaction with Pt atoms because the terminated S22? or S2? ligands on the edge exhibit much lower binding energy for Pt atoms compared with the apical S2? ligands on the terrace surface. The in situ electrochemical Pt‐deposited WS2 nanosheets with rich exposed edges can act as a highly active hybrid electrocatalyst to accelerate HER kinetics and exhibit commercial Pt‐like HER performance, especially in the alkaline media. 相似文献
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15.
Junfeng Xie Haichao Qu Jianping Xin Xinxia Zhang Guanwei Cui Xiaodong Zhang Jian Bao Bo Tang Yi Xie 《Nano Research》2017,10(4):1178-1188
Designing efficient electrocatalysts for the hydrogen evolution reaction (HER) has attracted substantial attention owing to the urgent demand for clean energy to face the energy crisis and subsequent environmental issues in the near future.Among the large variety of HER catalysts,molybdenum disulfide (MoS2) has been regarded as the most famous catalyst owing to its abundance,low price,high efficiency,and definite catalytic mechanism.In this study,defect-engineered MoS2 nanowall (NW) catalysts with controllable thickness were fabricated and exhibited a significantly enhanced HER performance.Benefiting from the highly exposed active edge sites and the rough surface accompanied by the robust NW structure,the defect-rich MoS2 NW catalyst with an optimized thickness showed an ultralow onset overpotential of 85 mV,a high current density of 310.6 mA·cm-2 at η =300 mV,and a low potential of 95 mV to drive a 10 mA.cm-2 cathodic current.Additionally,excellent electrochemical stability was realized,making this freestanding NW catalyst a promising candidate for practical water splitting and hydrogen production. 相似文献
16.
Changchun Sun Chao Wang Haijiao Xie Guangting Han Yuanming Zhang Haiguang Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(35):2302056
The development of high-efficiency non-precious metal electrocatalysts for alkaline electrolyte hydrogen evolution reactions (HER) is of great significance in energy conversion to overcome the limited supply of fossil fuels and carbon emission. Here, a highly active electrocatalyst is presented for hydrogen production, consisting of 2D CoSe2/Co3S4 heterostructured nanosheets along Co3O4 nanofibers. The different reaction rate between the ion exchange reaction and redox reaction leads to the heterogeneous volume swelling, promoting the growth of 2D structure. The 2D/1D heteronanostructures enable the improved the electrochemical active area, the number of active sites, and more favorable H binding energy compared to individual cobalt chalcogenides. The roles of the different composition of the heterojunction are investigated, and the electrocatalysts based on the CoSe2/Co3S4@Co3O4 exhibited an overpotential as low as 165 mV for 10 mA cm−2 and 393 mV for 200 mA cm−2 in 1 m KOH electrolyte. The as-prepared electrocatalysts remained active after 55 h operation without any significant decrease, indicating the excellent long-term operation stability of the electrode. The Faradaic efficiency of hydrogen production is close to 100% at different voltages. This work provides a new design strategy toward Co-based catalysts for efficient alkaline HER. 相似文献
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18.
《Advanced Materials Interfaces》2018,5(16)
For the growth of 2D transition metal dichalcogenides, such as molybdenum (MoS2) and tungsten disulfides (WS2), metalorganic chemical vapor deposition (MOCVD) routes are favorable due to their superior scalability, the possibility to tune the processing temperatures by a proper choice of reactants thus avoiding the need for a postdeposition treatment. Herein, the first example of a promising MOCVD route for the direct fabrication of MoS2 and WS2 layers under moderate process conditions is reported. This straightforward route is successfully realized by the combination of metalorganic precursors of Mo or W bearing the amidinato ligand with just elemental sulfur. The formation of stoichiometric hexagonal 2H‐MoS2 and 2H‐WS2 is demonstrated which is confirmed by Raman, X‐ray diffraction, and X‐ray photoelectron spectroscopy studies. The deposited layers are evaluated for their electrocatalytic activity in hydrogen evolution reaction as a proof of principle for application in water splitting devices. 相似文献
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20.
Akbar I. Inamdar Harish S. Chavan Bo Hou Chi Ho Lee Sang Uck Lee SeungNam Cha Hyungsang Kim Hyunsik Im 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(2)
To generate hydrogen, which is a clean energy carrier, a combination of electrolysis and renewable energy sources is desirable. In particular, for both the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in electrolysis, it is necessary to develop nonprecious, efficient, and durable catalysts. A robust nonprecious copper–iron (CuFe) bimetallic composite is reported that can be used as a highly efficient bifunctional catalyst for overall water splitting in an alkaline medium. The catalyst exhibits outstanding OER and HER activity, and very low OER and HER overpotentials (218 and 158 mV, respectively) are necessary to attain a current density of 10 mA cm?2. When used in a two‐electrode water electrolyzer system for overall water splitting, it not only achieves high durability (even at a very high current density of 100 mA cm?2) but also reduces the potential required to split water into oxygen and hydrogen at 10 mA cm?2 to 1.64 V for 100 h of continuous operation. 相似文献