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Recently, due to high price, resource shortage and unstable supply of cobalt, the development of low-cost cobalt-free Ni-rich cathodes has attracted extensive attention with the ever-increasing lithium-ion batteries (LIBs) industry. Selecting cost-effective elements to replace cobalt in Ni-rich cathodes is urgent. However, the principle of structural design of Ni-rich cathode remains unclear, hampering the selection of alternative elements. Herein, the cobalt-free cathodes of LiNi0.95Mg0.05O2 (NiMg) and LiNi0.95Mn0.05O2 (NiMn) are designed as alternatives to LiNi0.96Co0.04O2 (NiCo). NiMg has comparable cycle stability with NiCo, while NiMn has inferior cycle performance. Reverse Monte Carlo modelling was used to generate structural model and uncover local structure by fitting pair distribution function. It reveals Mn causes more severe Jahn-Teller distortions and disordered lattice host framework (Ni0.95M0.05O2, M = Co/Mn/Mg) than Co and Mg due to the strong size effect and coulomb interactions of Mn in Ni0.95Mn0.05O2 layer. The outstanding cycle stability of NiMg and NiCo originates from the ordered lattice host frameworks, which relieve stress and inhibit particle breakage during cycle. Meanwhile, the ordered lattice host framework induced guest Li+ disordering reduces Li+ diffusion energy barrier, improving the rate capability. This study provides a new perspective for the structural design of cobalt-free Ni-rich cathodes.
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Structurally ordered L10-PtM (M = Fe, Co, Ni and so on) intermetallic nanocrystals, benefiting from the chemically ordered structure and higher stability, are one of the best electrocatalysts used for fuel cells. However, their practical development is greatly plagued by the challenge that the high-temperature (>600 °C) annealing treatment necessary for realizing the ordered structure usually leads to severe particle sintering, morphology change and low ordering degree, which makes it very difficult for the gram-scale preparation of desirable PtM intermetallic nanocrystals with high Pt content for practical fuel cell applications. Here we report a new concept involving the low-melting-point-metal (M' = Sn, Ga, In)-induced bond strength weakening strategy to reduce Ea and promote the ordering process of PtM (M = Ni, Co, Fe, Cu and Zn) alloy catalysts for a higher ordering degree. We demonstrate that the introduction of M' can reduce the ordering temperature to extremely low temperatures (≤450 °C) and thus enable the preparation of high-Pt-content (≥40 wt%) L10-Pt-M-M' intermetallic nanocrystals as well as ten-gram-scale production. X-ray spectroscopy studies, in situ electron microscopy and theoretical calculations reveal the fundamental mechanism of the Sn-facilitated ordering process at low temperatures, which involves weakened bond strength and consequently reduced Ea via Sn doping, the formation and fast diffusion of low-coordinated surface free atoms, and subsequent L10 nucleation. The developed L10-Ga-PtNi/C catalysts display outstanding performance in H2-air fuel cells under both light- and heavy-duty vehicle conditions. Under the latter condition, the 40% L10-Pt50Ni35Ga15/C catalyst delivers a high current density of 1.67 A cm-2 at 0.7 V and retains 80% of the current density after extended 90,000 cycles, which exceeds the United States Department of Energy performance metrics and represents among the best cathodic electrocatalysts for practical proton-exchange membrane fuel cells.
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Na4Fe3(PO4)2(P2O7) (NFPP) is regarded as a promising cathode material for sodium-ion batteries (SIBs) owing to its low cost, easy manufacture, environmental purity, high structural stability, unique three-dimensional Na-ion diffusion channels, and appropriate working voltage. However, for NFPP, the low conductivity of electrons and ions limits their capacity and power density. The generation of NaFeP2O7 and NaFePO4 inhibits the diffusion of sodium ions and reduces reversible capacity and rate performance during the manufacturing process in synthesis methods. Herein, we report an entropy-driven approach to enhance the electronic conductivity and, concurrently, phase purity of NFPP as the superior cathode in sodium-ion batteries. This approach was realized via Ti ions substituting different ratios of Fe-occupied sites in the NFPP lattice (denoted as NTFPP-X, T is the Ti in the lattice, X is the ratio of Ti-substitution) with the configurational entropic increment of the lattice structures from 0.68 R to 0.79 R. Specifically, 5% Ti-substituted lattice (NTFPP-0.05) inducing entropic augmentation not only improves the electronic conductivity from 7.1 × 10-2 S/m to 8.6 × 10-2 S/m but also generates the pure-phase of NFPP (suppressing the impure phases of the NaFeP2O7 and NaFePO4) of the lattice structure, which is validated by a series of characterizations, including powder X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR), X-ray photoelectron spectroscopy (XPS), and density functional theory (DFT). Benefiting from the Ti replacement in the lattice, the optimal NTFPP-0.05 composite shows a high first discharge capacity (118.5 mAh g-1 at 0.1 C), superior rate performance (70.5 mAh g-1 at 10 C), and excellent long cycling life (1200 cycles at 10 C with capacity retention of 86.9%). This research proposes a new entropy-driven approach to improve the electrochemical performance of NFPP and reports a low-cost, ultrastable, and high-rate cathode material of NTFPP-0.05 for SIBs.
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As a potential catalyst for hydrogen evolution reaction (HER), tungsten nitride (W2N) has attracted extensive attention, due to its Pt-like characteristic. Nevertheless, insufficient active sites, slow electron transfer, and lack of scale-up nano-synthesis methods significantly limit its practical application. Constructing multi-component active centers and interface-rich heterojunctions to increase exposed active sites and modulate interface electrons is a very effective modification strategy. Therefore, a nano-heterostructure formed from tungsten nitride, tungsten phosphide and tungsten encapsulated in N, P co-doped carbon nanofiber (W2N/WP/W@NPC) was synthesized by a flexible and scalable electrospinning technology. Experimental results reveal that abundant heterojunctions are formed, electron transfer occurs between tungsten nitride and tungsten phosphide, and carbon nanofibers play a confinement role. The optimized W2N/WP/W@NPC-3 electrocatalyst demonstrates excellent HER catalytic activity and robust stability in both acidic and base media. Furthermore, the overall water splitting performance is tested using W2N/WP/W@NPC as the cathode through a two-electrode electrolyzer, which also exhibits impressive electrochemical performance.
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The optimal electrolyte for ultrahigh energy density (>400 Wh/kg) lithium-metal batteries with a LiNi0.8Co0.1Mn0.1O2 cathode is required to withstand high voltage (≥4.7 V) and be adaptable over a wide temperature range. However, the battery performance is degraded by aggressive electrode-electrolyte reactions at high temperature and high voltage, while excessive growth of lithium dendrites usually occurs due to poor kinetics at low temperature. Accordingly, the development of electrolytes has encountered challenges in that there is almost no electrolyte simultaneously meeting the above requirements. Herein, a high chaos electrolyte design strategy is proposed, which promotes the formation of weak solvation structures involving multiple anions. By tailoring a Li+-EMC-DMC-DFOB--PO2F2--PF6- multiple-anion-rich solvation sheath, a robust inorganic-rich interphase is obtained for the electrode-electrolyte interphase (EEI), which is resistant to the intense interfacial reactions at high voltage (4.7 V) and high temperature (45 °C). In addition, the Li+ solvation is weakened by the multiple-anion solvation structure, which is a benefit to Li+ desolventization at low temperature (-30 °C), greatly improving the charge transfer kinetics and inhibiting the lithium dendrite growth. This work provides an innovative strategy to manipulate the high chaos electrolyte to further optimize solvation chemistry for high voltage and wide temperature applications.
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NaClO4 and NaPF6, the most universally adopted electrolyte salts in commercial sodium-ion batteries (SIBs), have a decisive influence on the interfacial chemistry, which is closely related to electrochemical performance. The complicated and ambiguous interior mechanism of microscopic interfacial chemistry has prevented reaching a consensus regarding the most suitable sodium salt for high-performance SIB electrolytes. Herein, we reveal that the solvation structure induced by different sodium salt anions determines the Na+ desolvation kinetics and interfacial film evolution process. Specifically, the weak interaction between Na+ and PF6- promoted sodium desolvation and storage kinetics. The solvation structure involving PF6- induced the anion's preferential decomposition, generating a thin, inorganic compound-rich cathode-electrolyte interphase that ensured interface stability and inhibited solvent decomposition, thereby guaranteeing electrode stability and promoting the charge transfer kinetics. This study provides clear evidence that NaPF6 is not only more compatible with industrial processes but also more conducive to battery performance. Commercial electrolyte design employing NaPF6 will undoubtedly promote the industrialization of SIBs.
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Superior specific capacity, high-rate capability, and long-term cycling stability are essential to anode materials in sodium-ion batteries, and conductive metal-organic frameworks (cMOF) with good electronic and ionic conductivity may satisfy these requirements. Herein, conductive neodymium cMOF (Nd-cMOF) produced in situ on the zeolitic imidazolate framework (ZIF)-derived carbon fiber (ZIF-CFs) platform is used to synthesize the Nd-cMOF/ZIF-CFs hierarchical structure. Four types of ZIFs with different pore diameters are prepared by electrospinning. In this novel structure, ZIF-CFs provide the electroconductivity, flexible porous structure, and mechanical stability, while Nd-cMOF provides the interfacial kinetic activity, electroconductivity, ample space, and volume buffer, consequently giving rise to robust structural integrity and excellent conductivity. The sodium-ion battery composed of the Nd-cMOF/ZIF-10-CFs anode has outstanding stability and electrochemical properties, such as a specific capacity of 480.5 mAh g-1 at 0.05 A g-1 as well as capacity retention of 84% after 500 cycles.
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How to enhance the sense of meaning in life is a topic deserving of extensive research. The impact of creativity on finding meaning in life, however, has not been thoroughly explored in empirical research. This paper studies the relationship between creativity and meaning in life, and the cognitive and emotional factors underlying this relationship. The participants of this study were 359 Chinese college students (38 males and 321 females; aged from 17 to 41 years) in learning English as a foreign language (EFL). Four instruments were utilized in the survey, namely, the Kaufman Domains of Creativity Scale (K-DOCS), the Positive Affect Scale, the General Self-Efficacy Scale (GSES), and the Meaning in Life Questionnaire (MLQ). The correlation analysis shows that creativity, positive affect, general self-efficacy, and meaning in life are all positively correlated. According to a bootstrap method to assess the significance of the indirect effect, general self-efficacy and positive affect play multiple mediating roles in the relationship between creativity and meaning in life via three mediating pathways: general self-efficacy alone, positive affect alone, and the effect of general self-efficacy on positive affect. The mediating effect accounts for nearly half (44.18%) of the total effect. This study examines the theoretical connection between creativity and meaning in life, and uncovers the psychological process that underlies this connection. On a practical level, these results indicate that stimulating Chinese college students to engage in creative activities in various fields can enhance their sense of meaning in life.
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The harsh working environments of proton exchange membrane fuel cells (PEMFCs) pose huge challenges to the stability of Pt-based alloy catalysts. The widespread presence of metallic bonds with significantly delocalized electron distribution often lead to component segregation and rapid performance decay. Here we report L10 -Pt2 CuGa intermetallic nanoparticles with a unique covalent atomic interaction between Pt-Ga as high-performance PEMFC cathode catalysts. The L10 -Pt2 CuGa/C catalyst shows superb oxygen reduction reaction (ORR) activity and stability in fuel cell cathode (mass activity=0.57â A mgPt -1 at 0.9â V, peak power density=2.60/1.24â W cm-2 in H2 -O2 /air, 28â mV voltage loss at 0.8â A cm-2 after 30 000â cycles). Theoretical calculations reveal the optimized adsorption of oxygen intermediates via the formed biaxial strain on L10 -Pt2 CuGa surface, and the durability enhancement stems from the stronger Pt-M bonds than those in L11 -PtCu resulted from Pt-Ga covalent interactions.
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Sodium metal, with a high theoretical specific capacity of 1165 mAh g-1 , is the ultimate anode for sodium batteries, yet how to deal with the inhomogeneous and dendritic sodium deposition and the infinite relative dimension change of sodium metal anodes during sodium depositing/stripping is still challenging. Here, a facile fabricated sodiuphilic 2D N-doped carbon nanosheets (N-CSs) are proposed as sodium host material for sodium metal batteries (SMBs) to prevent dendrite formation and eliminate volume change during cycling. Revealing from combined in situ characterization analyses and theoretical simulations, the high nitrogen content and porous nanoscale interlayer gaps of the 2D N-CSs can not only concede dendrite-free sodium stripping/depositing but also accommodate the infinite relative dimension change. Furthermore, N-CSs can be easily process into N-CSs/Cu electrode via traditional commercial battery electrode coating equipment that pave the way for large-scale industrial applications. On account of the abundant nucleation sites and sufficient deposition space, N-CSs/Cu electrodes demonstrate a superior cycle stability of more than 1500 h at a current density of 2 mA cm-2 with a high coulomb efficiency of more than 99.9% and ultralow nucleation overpotential, which enable reversible and dendrites-free SMBs and shed light on further development of SMBs with even higher performance.
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The electrochemical performances of lithium metal batteries are determined by the kinetics of interfacial de-solvation and ion transport, especially at low-temperature environments. Here, a novel electrolyte that easily de-solvated and conducive to interfacial film formation is designed for low-temperature lithium metal batteries. A fluorinated carboxylic ester, diethyl fluoromalonate (DEFM), and a fluorinated carbonate, fluoroethylene carbonate (FEC) are used as solvents, while high concentrated lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) is served as the solute. Through tailoring the electrolyte formulation, the lithium ions in the high concentrated fluorinated carboxylic ester electrolyte are mainly combined with anions, which weakens the bonding strength of lithium ions and solvent molecules in the solvation structure, beneficial to the de-solvation process at low temperature. The fluorinated carboxylic ester (FCE) electrolyte enables the LiFePO4 (LFP) | Li half-cell achieves a high capacity of 91.9 mAh g-1 at -30 °C, with high F content in the interface. With optimized de-solvation kinetics, the LFP | Li full cell remains over 100 mAh g-1 at 0 °C after cycling 100 cycles. Building new solvents with outstanding low-temperature properties and weaker solvation to match with Li metal anode, this work brings new possibilities of realizing high energy density and low temperature energy storage batteries.
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Li-rich and Ni-rich layered oxides as next-generation high-energy cathodes for lithium-ion batteries (LIBs) possess the catalytic surface, which leads to intensive interfacial reactions, transition metal ion dissolution, gas generation, and ultimately hinders their applications at 4.7 V. Here, robust inorganic/organic/inorganic-rich architecture cathode-electrolyte interphase (CEI) and inorganic/organic-rich architecture anode-electrolyte interphase (AEI) with F-, B-, and P-rich inorganic components through modulating the frontier molecular orbital energy levels of lithium salts are constructed. A ternary fluorinated lithium salts electrolyte (TLE) is formulated by mixing 0.5 m lithium difluoro(oxalato)borate, 0.2 m lithium difluorophosphate with 0.3 m lithium hexafluorophosphate. The obtained robust interphase effectively suppresses the adverse electrolyte oxidation and transition metal dissolution, significantly reduces the chemical attacks to AEI. Li-rich Li1.2 Mn0.58 Ni0.08 Co0.14 O2 and Ni-rich LiNi0.8 Co0.1 Mn0.1 O2 in TLE exhibit high-capacity retention of 83.3% after 200 cycles and 83.3% after 1000 cycles under 4.7 V, respectively. Moreover, TLE also shows excellent performances at 45 °C, demonstrating this inorganic rich interface successfully inhibits the more aggressive interface chemistry at high voltage and high temperature. This work suggests that the composition and structure of the electrode interface can be regulated by modulating the frontier molecular orbital energy levels of electrolyte components, so as to ensure the required performance of LIBs.
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Dopants and defects are crucial for multifunctional carbon-based metal-free electrocatalysts, but the rational design and facile production remain as a big challenge. Herein, we report a novel strategy using salt-assisted pyrolysis of derivatized fullerenes to fabricate defect-rich and N-doped carbon nanosheets. Molecular level modification of C60 via amination and hydroxylation gives rise to well-defined fullerol molecules bearing N-containing groups (FNG). Subsequent calcination of FNG and NaCl at 750 °C generates porous carbon nanosheets (FNCNs-750) and turns the N-containing groups into high-level N dopants (12.43â at.%). Further pyrolysis of FNCNs-750 at 900 °C (FNCNs-900) leads to a reduced N content populated by graphitic-N. Meanwhile, abundant intrinsic defects (e. g., topological defects and edges) are created due to the breakdown of fullerene cages and partial removal of edged N atoms. These structural features endow FNCNs-900 with outstanding trifunctional catalytic performance, better than or close to the noble metal-based benchmark catalysts.
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Fe-N-C represents the most promising non-precious metal catalysts (NPMCs) for the oxygen reduction reaction (ORR) in fuel cells, but often suffers from poor stability in acid due to the dissolution of metal sites and the poor oxidation resistance of carbon substrates. In this work, silicon-doped iron-nitrogen-carbon (Si/Fe-N-C) catalysts were developed by inâ situ silicon doping and metal-polymer coordination. It was found that Si doping could not only promote the density of Fe-Nx /C active sites but also elevated the content of graphitic carbon through catalytic graphitization. The best-performing Si/Fe-N-C exhibited a half-wave potential of 0.817â V vs. reversible hydrogen electrode in 0.5 m H2 SO4 , outperforming that of undoped Fe-N-C and most of the reported Fe-N-C catalysts. It also exhibited significantly enhanced stability at elevated temperature (≥60 °C). This work provides a new way to develop non-precious metal ORR catalysts with improved activity and stability in acidic media.
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T helper 17 (Th17) cells contribute to the pathogenesis of inflammatory bowel diseases (IBD). However, their heterogeneity and regulatory mechanisms in IBD are not completely disclosed. A mouse colitis model was established. Th17 cells were enriched from the mesenteric lymph nodes (mLN) and lamina propria (LP). The phenotypes and functions of Th17 subsets were analyzed by flow cytometry, Immunoblotting, and real-time RT-PCR. The contributions of the Th17 subsets to colitis pathogenesis were evaluated by histology, ELISA, and flow cytometry after adoptive transfer. Smoothened (SMO), GLI family zinc finger 1 (Gli1), and GLI family zinc finger 3 (Gli3) were markedly up-regulated while Patched 1 (PTCH1) was down-regulated in LP Th17 cells in colitic lamina propria. Based on the expression of PTCH1 and C-C motif chemokine receptor 6 (CCR6), LP Th17 cells were divided into a PTCH1lowCCR6low Th17 subset and a PTCH1highCCR6high Th17 subset. The former expressed higher T-bet, IFN-γ, TNF-α, IL-1ß, and GM-CSF but lower IL-17A, IL-22, IL-17F, and Gli3 than the latter. The PTCH1highCCR6high Th17 subset was more resistant to polarization towards T helper 1 (Th1) than the PTCH1lowCCR6low Th17 subset. Moreover, the PTCH1highCCR6high Th17 subset was more competent to maintain Th17 identity. The PTCH1highCCR6high Th17 subset induced less severe colitis than the PTCH1lowCCR6low Th17 subset. PTCH1highCCR6high Th17 cells are Th17 cells whereas PTCH1lowCCR6low Th17 cells are Th1-like Th17 cells. Our study deepens the understanding of Th17 heterogeneity and plasticity in colitis.
Asunto(s)
Colitis , Enfermedades Inflamatorias del Intestino , Ratones , Animales , Colitis/metabolismo , Membrana Mucosa/metabolismo , Membrana Mucosa/patología , Células Th17/metabolismo , Receptores de Quimiocina/metabolismoRESUMEN
The LiNi0.8Co0.1Mn0.1O2 (Ni-rich NCM) cathode materials suffer from electrochemical performance degradation upon cycling due to detrimental cathode interface reactions and irreversible surface phase transition when operating at a high voltage (≥4.5 V). Herein, a traditional carbonate electrolyte with lithium difluoro(oxalato)borate (LiDFOB) and tris(trimethylsilyl)phosphate (TMSP) as dual additives that can preferentially oxidize and decompose to form a stable F, B and Si-rich cathode-electrolyte interphase (CEI) that effectively inhibits continual electrolyte decomposition, transition metal dissolves, surface phase transition and gas generation. In addition, TMSP also removes trace H2O/HF in the electrolyte to increase the electrolyte stability. Owing to the synergistic effect of LiDFOB and TMSP, the Li/LiNi0.8Co0.1Mn0.1O2 half cells exhibit the capacity retention 76.3% after 500 cycles at a super high voltage of 4.7 V, the graphite/LiNi0.8Co0.1Mn0.1O2 full cells exhibit high capacity retention of 82.8% after 500 cycles at 4.5 V, and Li/LiNi0.8Co0.1Mn0.1O2 pouch cells exhibit high capacity retention 94% after 200 cycles at 4.5 V. This work is expected to provide an effective electrolyte optimizing strategy compatible with high energy density lithium-ion battery manufacturing systems.
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A one-step coprecipitation process is designed to synthesize zinc hexacyanoferrate (ZnHCF) cathodes in aqueous zinc-ion batteries (ZIBs). The morphology of the cathode is influenced by the concentration of the precursor solution and valence of iron ions. The rhombohedral ZnHCF sample exhibits high crystallinity on the microscale in the cut-angle cubic structure, whereas Na-rich NaZnHCF contains many interstitial water molecules in the rhombic nanoplates. Both samples show effective insertion of Zn ions in the aqueous ZnSO4 solution. ZnHCF shows a specific capacity of 66.7 mA h g-1, a redox voltage of 1.73 V, and fast decline in a few cycles. On the other hand, NaZnHCF has a lower specific capacity of 48.2 mA h g-1, showing two voltage platforms and robust cycling stability. However, owing to serious side reactions, both samples have low Columbic efficiency. To improve the properties such as Coulombic efficiency, specific capacity, and cycling stability, Ni ions are introduced by adding 10 wt % NiSO4 to the ZnSO4 electrolyte. The ZnHCF cathode in the Ni-containing electrolyte has the best properties such as a high specific capacity of 71.2 mA h g-1 at a current density of 100 mA g-1, 93% retention of the Coulombic efficiency, and a good rate performance manifested by a reversible capacity of 58.2 mA h g-1 at 1 A g-1. The results reveal a strategy to improve the electrochemical properties of aqueous ZIBs by modifying the electrolytes.
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Successful intelligence theory suggests that creativity is necessary for personal achievement outside of intelligence. Unlike intelligence, creativity can develop in a supportive environment. People should consider the situation of disadvantaged groups, which are characterized by low personal achievement and a bad growth environment in creativity evaluation from a caring perspective. This study focuses on the effect of the creator's situation on creative evaluation and the role of the rater's empathy (i.e., cognitive empathy and affective empathy) and sympathy in creative evaluation. Four pairs of creator's situations (by age, physical state, family situation, and economic state) were designed to represent people with disadvantages or advantages. A between-subject design was used with 590 undergraduate students randomly assigned to eight sub-conditions. The participants were asked to assess three products in eight situations. The rater's empathy and sympathy in creativity evaluation were explored in the overall disadvantage (N = 300) and advantage (N = 290) conditions. The results showed that the participants only provided significantly higher ratings to the creative product made by a child. Cognitive empathy only predicted a creative rating under disadvantaged conditions, and affective empathy negatively moderated this effect. Affective empathy only predicted a creative rating under advantage conditions, and cognitive empathy positively moderated this effect. Affective empathy only predicted a creative rating under advantage conditions, and cognitive empathy positively moderated this effect. The possible mechanisms of the effect and implications for the establishment of a supportive environment for creativity and creativity teaching practice were discussed.
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The small energy density and chemomechanical degradation of layered manganese oxide limit practical application to sodium-ion batteries (SIBs). Typically, Na2Mn3O7 shows a low redox plateau at 2.1 V versus Na/Na+, and the oxygen redox reaction at a high voltage causes structural collapse. Herein, a Na vacancy-induced boron doping strategy is demonstrated to improve the properties. Boron is incorporated into selective sites in the lattice in the center of the MnO6 octahedral ring at the O-layer. Bonding of boron in the TM layer enhances the electrochemical activity of low-valence Mn, giving rise to two reversible redox peaks at 2.45 and 2.55 V to enhance the average redox voltage. At the same time, the O 2p chemical state becomes weaker around the Fermi level, thus suppressing oxygen overoxidation for the high charge state and strengthening the layered structure during the redox reactions. The reduced Mn-O covalency and small diffusion barrier energy stemming from bonding of boron in the oxygen layer produce excellent rate characteristics. Modulation of the Mn 3d and O 2p orbital in Na2Mn3O7 by Na vacancies leads to selective doping of boron at different sites, and our results reveal that it is an important strategy for studying transition-metal-oxide-layered electrode materials.
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The development of highly efficient and durable water electrolysis catalysts plays an important role in the large-scale applications of hydrogen energy. In this work, protrusion-rich Cu@NiRu core@shell nanotubes are prepared by a facile wet chemistry method and used for catalyzing hydrogen evolution reaction (HER) in an alkaline environment. The protrusion-like RuNi alloy shells with accessible channels and abundant defects possess a large surface area and can optimize the surface electronic structure through the electron transfer from Ni to Ru. Moreover, the unique 1D hollow structure can effectively stabilize RuNi alloy shell through preventing the aggregation of nanoparticles. The synthesized catalyst can achieve a current density of 10 mA cm-2 in 1.0 m KOH with an overpotential of only 22 mV and show excellent stability after 5000 cycles, which is superior to most reported Ru-based catalysts. Density functional theory calculations illustrate that the weakened hydrogen adsorption on Ru sites induced by the alloying with Ni and active electron transfer between Ru and Ni/Cu are the keys to the much improved HER activity.