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Aqueous zinc-air battery (ZAB) has attractive features as the potential energy storage system such as high safety, low cost and good environmental compatibility. However, the issue of dendrite growth on zinc metal anodes has seriously hindered the development of ZAB. Herein, the N-doped carbon cloth (NC) prepared via magnetron sputtering is explored as the substrate to induce the uniform nucleation of zinc metal and suppress dendrite growth. Results show that the introduction of heteroatoms accelerates the migration and deposition kinetics of Zn2+ by boosting the desolvation process of Zn2+, eventually reducing the nucleation overpotential. Besides, theoretical calculation results confirm the zincophilicity of N-containing functional group (such as pyridine N and pyrrole N), which can guide the nucleation and growth of zinc uniformly on the electrode surface by both promoting the redistribution of Zn2+ in the vicinity of the surface and enhancing its interaction with zinc atoms. As a result, the half-cell assembled with magnetron sputtered carbon cloth achieves a high zinc stripping/plating coulombic efficiency of 98.8% and long-term stability of over 500 cycles at 0.2 mA cm-2. And the Coulombic efficiency reached about 99.5% at the 10th cycle and maintained for more than 210 cycles at a high current density of 5.0 mA cm-2. The assembled symmetrical battery can deliver 220 plating/stripping cycles with ultra-low voltage hysteresis of only 11 mV. In addition, the assembled zinc-air full battery with NC-Zn anode delivers a high special capacity of about 429 mAh gZn-1 and a long life of over 430 cycles. The effectiveness of surface functionalization in promoting the transfer and deposition kinetics of Zn2+ presented in this work shows enlightening significance in the development of metal anodes in aqueous electrolytes.

To improve the thermal properties of aluminum (Al) in the energetic system, a coated structure with ammonium perchlorate (AP) was prepared by a facile approach. And N, N-Dimethylformamide (DMF) was chosen as an ideal solvent based on heterogeneous nucleation theory and molecular dynamics simulation. This coated structure could enlarge the contact area and improve the reaction environment to enhance the thermal properties. The addition of AP could accelerate oxidation temperature of Al with around 17.5 °C. And the heat release of 85@15 composition rises to 26.13 kJ/g and the reaction degree is 97.6% with higher peak pressure (254.6 kPa) and rise rate (1.397 MPa/s). An ideal ratio with 15 wt% AP was probed primarily. The high energy laser-induced shockwave experiment was utilized to simulate the reaction behavior in hot field. And the larger activated mixture of coated powder could release more energy to promote the growth of shockwave with higher speed up to 518.7 ± 55.9 m/s. In conclusion, 85@15 composition is expected to be applied in energetic system as a novel metal fuel.

In this study, metallic glass is designed tunable for promising functional applications via a facile and stable, one-step process. Creative approach about alloy design and process is based on the unique properties of the Ti-Cu-Ni-Sn metallic glass that are afforded by the varying oxygen affinities of the four constituent elements. This metallic glass exhibits homogeneous nucleation of oxides and uniform formation of the various metal oxides. The alloy design and hydrothermal synthesis to customize the metallic glasses are the most critical factors that determine the characteristics of the metal oxides and the resulting nanostructures and photoelectrode properties. This enables the desired element to be selectively grown via a facile single-step process. These results provide a promising road map for the application of metallic glasses to photoelectrochemical (PEC) solar water splitting, as well as various other new possibilities.

Aqueous zinc anodes have attracted the attention of many researchers owing to their high safety, low cost, and high theoretical specific capacity. However, its practical application is severely limited by the dendrite growth on zinc anode. Herein, we develop an intrinsically zincophobic barium-titanate protective layer with a porous structure to suppress the zinc dendrite formation by homogenizing the ion distribution on the anode surface, increasing the nucleation sites, and limiting the irregular zinc growth. Based on these synergistic effects, the coated zinc anode can exhibit long cycle life (840 h at 0.5 mA/cm2 for 0.5 mAh/cm2) and low voltage hysteresis (36 mV). This work can provide a feasible direction for the design of intrinsically zincophobic coating materials to uniformize the zinc stripping and plating.

Homogeneous crystal nucleation is prone to formation of defects and often experiences heterogeneities, the inferences of which are crucial in processing crystalline materials and controlling their physical properties. It has been debated in literature whether the associated heterogeneities are an integral part of the homogenous nucleation. In this study by integrating a probabilistic approach with large-scale molecular dynamics simulations based on the most advanced high-temperature interatomic potentials, we attempt to address the ambiguity over the sources and mechanisms of heterogeneities in homogenous nucleation during solidification of pure melts. Different classes of structured metals are investigated for this purpose, including face-centered cubic aluminum, body-centered cubic iron, and hexagonal close-packed magnesium. The results reveal, regardless of the element type or the solidified crystal structure, that the densification process of liquid metals is accompanied by short-range orderings of atoms prior to the formation of crystals, controlling the heterogeneities during homogenous nucleation.

The microstructure evolution and mechanical properties of Mg–6Zn–0.5Ce–xMn (x = 0 and 1 wt.%) wrought magnesium alloys were researched, and the morphologies and role of Mn element in the experimental alloys were analyzed. The research shows that all of Mn elements form the α-Mn pure phases, which do not participate in the formation of other phases, such as the τ-phases. The mechanical properties of Mn-containing alloys in as-extruded and aged states are superior to Mn-free alloys. During the hot extrusion process, the dispersed fine α-Mn particle phase hinders the migration of grain boundaries and inhibits dynamic recrystallization, which mainly takes effect of grain refining and dispersion hardening. During the aging treatments, the dispersed fine α-Mn particle phase not only hinders the growth of the solution-treated grains, but also becomes the nucleation cores of β 1 ′ rod-like precipitate phase, which is conducive to increasing the nucleation rate of the precipitate phase. For the aged alloy, the Mn addition mainly takes effect of grain refining and promoting aging strengthening.

Metal skeletons, such as Nickel Foam (NF) has attracted worldwide interests as stable host for lithium metal anode because of its high stability, large specific surface area and high conductivity. However, most metal skeletons have lithophobic surface and uneven current distribution that result in sporadic lithium nucleation and uncontrolled dendrites growth. Herein, we describe a sequential immersing strategy to generate interwoven Nickel(II)-dimethylglyoxime (Ni-DMG) nanowires at NF to obtain composite skeleton (NDNF), which can be used as an stable host for Li metal storage. The Ni-DMG has proved effective to realize uniform lithium nucleation and dendrite-free lithium deposition. Combing with the three dimensional (3D) hierarchical porous structure, the composite host shows a significantly improved coulombic efficiency (CE) than pristine commercial nickel foam. Moreover, the corresponding Li||Li symmetrical cells can run more than 700 h with low voltage hysteresis 22 mV at 1.0 mA/cm2, and Li@NDNF||LiFePO4 full-cell exhibits a high capacity retention of 82.03% at 1.0 C during 630 cycles. These results proved the effectiveness of metal-organic complexes in governing Li metal growth and can be employed as a new strategy for dendrite-free Li metal anode and safe Li metal batteries (LMBs).

The development of structural materials resistant to harsh radiation environments requires an in-depth understanding of the early stage of the aging processes. In radiation environments with high transmutation helium production rates such as in fusion and spallation applications, even materials with otherwise acceptable radiation stability may suffer from radiation embrittlement related to helium bubble formation. While theoretical modeling of helium-assisted cavity nucleation in pure metals and simple alloys provides some useful guidelines at the atomic scale level, these, however, do not overlap with the size resolution of available experimental techniques. In this study, we employed slow positron beam spectroscopy to characterize the nucleation and growth of nano-scale helium bubbles in martensitic steels strengthened by thermodynamically stable nano-oxide dispersoids. In combination with transmission electron microscopy, we experimentally characterized the evolution of helium bubbles from small clusters of radiation-induced vacancies to large cavities well resolvable by TEM. Superior radiation resistance of oxide-dispersion strengthened steels dominates only in the early stages of bubble evolution, where positron lifetime measurements provide a missing piece of the microstructural puzzle conventionally constructed by TEM.

This study aims at investigating the effect of the substrate material on growth mechanism and also microstructure of Ta2O5 thin films. For this purpose, atomic force microscopy, scanning electron microscopy, and interferometry analyses were implemented to reveal the influence of silicon wafer and amorphous BK7 glass substrates on the nucleation and growth mechanisms of Ta2O5 thin films deposited via the radio frequency magnetron sputtering technique. Results indicated that those films with finer morphologies had relatively higher nucleation densities. Compared with BK7 glass substrate, crystals formed on the silicon wafer were shown to be finer and had lower mean areas in more nucleation sites. Moreover, optical properties and morphological characteristics of the films on the silicon substrates had much more endurance after the annealing treatment. It was observed that shift in the transmission spectra of the deposited films after the treatment was insignificant, implying high packing density of the films. However, a 6-nm shift in the transmission spectra indicated low density and high porosity of the films. Finally, atomic force microscopy analysis along with the light scattering measurements confirmed the formation of a low-roughness film on the silicon wafer substrates.

To enhance the corrosion resistance of an aluminum (Al) 6082 alloy, our research used electroless deposition to coat a trio sequence of Zn-Cu-Sn layers: zinc, copper and tin. To isolate the reactions and micro-mechanisms in the tin coating, the Zn-Cu layering parameters of time, temperature, and bath concentration were held constant while varying those during the Sn electroless deposition. Microstructures and layer thicknesses of the coated samples were studied using both optical and scanning electron microscopy (SEM). Local chemical compositions were analyzed using energy dispersive spectroscopy (EDS). Tin deposition on the Cu layer starts with a displacement reaction formed by the nucleation of discontinuous bulges that gradually grow into inhomogeneous crowns. During Sn deposition, surface Cu consumption and bath composition varies hindering access to displacement reactants, thus curtailing the significance of displacement. However, deposition continues via reduction and disproportionation directly tied to the solution. Peak layer quality was deposited at a temperature of 45 oC with a 1.5 times concentration for 1200 sec. Anti-corrosion behavior of the Sn-coated sample was examined by Electrochemical Impedance Spectroscopy (EIS) to detect notable enhancement.

The uncontrollable Li dendritic plating and infinite volumetric expansion significantly plague the practical applications of lithium (Li) metal, which is regarded as the most promising high-energy-density anode material for rechargeable batteries. The well regulated Li-ion (Li+) flux distribution and Li deposition is the prerequisite for feasible Li-metal batteries. In this work, the Li migration, nucleation and growth behavior are investigated with a lithiophilic CoP-doped carbon nanofibers (CoP@CNF)-guided self-standing substrate. The high adsorption effect and low migration barrier of CoP to Li+ lead to the reversible conversion reaction between Li and CoP, enabling an even charge transportation and a homogeneous Li+ concentration gradient. The uniform nucleation and dense electrodeposition of Li over through the CoP@CNF is demonstrated via combined in-situ/ex-situ morphologic and electrochemical characterizations. Benefiting from the small nucleation and growth overpotential of Li, the symmetrical cell of CoP@CNF@Li can steadily operate under 0.5 mA cm−2 over 2000 h with a low voltage hysteresis of ca. 12 mV. When paired with a LiFePO4 cathode, a specific capacity exceeding 90 mAh g−1 up to 1000 cycles is achieved at 5 C (1 C = 170 mA g−1), demonstrating the dendritic Li suppression capability of the CoP@CNF@Li composite anode.

Lithium (Li) metal batteries have received extensive research focusing on the dendrite growth issue on account of the high chemical activity of Li anode. While, thermal safety, as one of the important security concerns facing the further application, gets little attention. Here, the high-performance polyimide film is successfully developed to enhance the safety margin based on the excellent mechanical strength and heat resistance corresponding to the traditional separator. And, the polyimide film with the MoS2 coating made by spraying method as the composite separator can not only improve the wettability to the electrolyte, but also in-situ form an artificial layer with the low nucleation barrier for the Li ions. When used in both the coin cell and the pouch cell, all achieve the outstanding cycling stability and the coulombic efficiency. Specially, the in-situ Li ions nucleation behaviors are investigated by optical microscopy in the capillary cell. The electric field intensity at the Li anode surface is also simulated by COMSOL Multiphysics to further elucidate the effect of the coating.

Plant extracts are known to modulate calcium oxalate (CaOx) crystallization. One of these is Globularia, the root and flower. Medicinals plants has been demonstrated to be an efficient inhibitor of CaOx crystal growth; however, its inhibitory activity against other events in CaOx crystallization has not been fully investigated. To assess the potential of Globularia as an effective inhibitor, its effects on CaOx crystal nucleation and aggregation were evaluated. Nucleation and aggregation of CaOx crystals were studied by artificial urine is prepared by mixing and stirring two equal volumes of 50 ml of solutions A and B at constant temperature (37°C). In the nucleation assay, crystallization was induced by mixing calcium chloride and sodium oxalate, The addition of extracts Globularia flower and root , acts on the phase of growth crystallisation ; the rate of inhibition capacity in concentration 100 % is 96.09% , and 96.77% for concentration 75% respectively, On note that these inhibitors developed an inhibition important on the low concentration. Globularia is an efficient inhibitor of crystal nucleation and aggregation. Its presence in the kidneys and urine may protect subjects against CaOx crystallization and kidney stone formation.

In this study, the crystallization behavior of Al86Ni8Y6 upon rapid cooling from the equilibrium melt is investigated and the crystalline phases that compete with the glass formation are identified. Al86Ni8Y6 is one of the best glass formers in the ternary Al-Ni-Y system. Contrary to previous studies suggesting α-Al as the primary phase upon quenching, this study reveals that glass formation is strongly restricted by the formation of the primary precipitating ternary intermetallic compound Al23Ni6Y4. The nucleation of Al23Ni6Y4 appears to be triggered by yttrium oxide particles present in the melt acting as heterogeneous nucleation sites. Once the primary phase Al23Ni6Y4 has been formed, further crystallization of the Ni and Y depleted melt occurs as α-Al. The corresponding results are shown and discussed with respect to their effects on the glass formation.

Uncontrollable Li dendrite growth and infinite volume fluctuation during durative plating and stripping process gravely hinder the application of metallic Li electrode in lithium-oxygen batteries. Herein, oxygen vacancy-rich TiO2 (Vo-TiO2) nanoparticles (NPs) uniformly dispersing on Ti3C2Tx (Vo-TiO2/Ti3C2Tx) with excellent lithiophilicity feature are presented as effective composite anodes, on which a dense and uniform Li growth behavior is observed. Based on electrochemical studies, mutiphysics simulation and theoretical calculation, it is found that Vo-TiO2 coupling with three dimensional (3D) conductive Ti3C2Tx MXene forms highly ordered lithiophilic sites which succeed in guiding Li ions flux and adsorption, thus modulating the uniform Li nucleation and growth. As a result, this composite electrode is capable of preserving Li with high areal capacity of ~10 mAh cm−2 without the presence of dendrites and large volume expansion. Consequently, the as-prepared Vo-TiO2/Ti3C2Tx@Li anode shows outstanding performance including low voltage hysteresis (~19 mV) and superior durability (over 750 h). When assembling with the Vo-TiO2/Ti3C2Tx@Li anodes, lithium-oxygen batteries also deliver enhanced cycling stability and improved rate performance. This work demonstrates the effectiveness of oxygen vacancies in guiding Li nucleating and plating behavior at initial stage and brings a promising strategy for promoting the development of advanced Li metal-based batteries.

Despite its cost-effectiveness and intrinsic safety, the aqueous zinc-iodine battery is still struggling with the rapid performance degradation arising from the uneven deposition of the zinc anode and the dissolution of the iodine cathode. An effective solution of addressing the above issues simultaneously is urgently needed. Here we propose a strategy of using one porous carbon to modify the zinc anode and immobilize the iodine active materials. Zinc citrate-derived porous carbon is selected as a study model. The conductive porous carbon can not only greatly reduce the zinc nucleation barrier, and guide a uniform deposition of zinc ions, but also notably suppress the dissolution of iodine species and enhance the reaction kinetics. As a consequence, the optimized zinc-iodine battery exhibits capacity retention of 88.1% after 3000 cycles at 12C, finishing a cycle within 5 min.

Ti3AlC2/Al2O3 composites were synthesized by aluminothermic reduction of TiO2/Al/C and TiO2/Al/TiC. The effects of carbon sources (carbon black and TiC), steps heating-up profile, and Al-excess of raw materials composition on the Ti3AlC2 content in final products were investigated. The results showed that in contrast with carbon black, TiC used as a carbon source is beneficial to the formation of Ti3AlC2 at lower temperatures. However, Ti3AlC2 content in the product with carbon black was improved by the steps heating-up profile and Al-excess, promoting intermediate phases TiAl3 and TiC. Furthermore, the formation mechanisms of Ti3AlC2 with different carbon sources in aluminothermic reaction systems were also elucidated. For the TiO2/Al/C system, Ti3AlC2 is precipitated from the Ti–Al melt at high temperatures via the dissolution-precipitation mechanism, which has slower nucleation but faster growth. In contrast, in the TiO2/Al/TiC system, Ti3AlC2 is mainly growing from the intact TiC grains through the epitaxial nucleation mechanism, which has faster nucleation but lower growth.

The property evaluation of Aluminum alloys a quite a challenging task and is an essential one to achieve improved mechanical and metallurgical properties during casting. This paves the way for the present research, in which the casting of commercial A356 and A319 Al alloys have been performed under stationary and vibratory state. The vibrational recurrence has been varied between 0 Hz and 400 Hz with a constant amplitude of 15 μm during casting. Thereafter, the quality of both casted materials has been evaluated by measuring their yield strength, ultimate tensile strength and % elongation. Experimental results revealed that the higher intensity of oscillation improves mechanical properties with the reduced grain size of α-Al. It has been also observed that the fraction of nucleation sites is increased due to the vibration.

Copper is a most widely used substrate for Li deposition and dissolution in lithium metal anodes, which are complicated by the formation of solid-electrolyte-interphases (SEIs) whose physical and chemical properties can affect Li deposition and dissolution significantly. However, initial Li nucleation and growth on bare Cu creates Li nuclei that only partially cover the Cu surface so that SEI formation could proceed not only on Li nuclei but also on the bare region of the Cu surface with different kinetics, which may affect the follow-up processes distinctively. In this paper, we employ in-situ atomic force microscopy (AFM) together with X-ray photoelectron spectroscopy (XPS) to investigate how SEIs formed on Cu surface, without Li participation, and on the surface of growing Li nuclei, with Li participation, affect the components and structures of the SEIs, and how the formation sequence of the two kinds of SEIs along with Li deposition affect subsequent dissolution and re-deposition processes in a pyrrolidinium-based ionic liquid electrolyte containing small amount of water. Nanoscale in-situ AFM observations show that sphere-like Li deposits may have differently conditioned SEI-shells, depending on whether Li nucleation is precedent with formation of the SEI on Cu. Models of integrated-SEI shells and segmented-SEI shells are proposed to respectively describe SEI shells formed on Li nuclei and the SEI shells sequentially-formed on Cu and then on Li nuclei. “Top-dissolution” are observed for both types of shelled Li deposits, but the integrated-SEI shells only show wrinkles which can be recovered upon Li re-deposition while the segmented-SEI shells are apparently top-opened due to mechanical stresses introduced at the junctions of the top regions and become “dead” SEIs which forces subsequent Li nucleation and growth in the interstice of the dead SEIs. Our work provides insights on the impact mechanism of SEIs on Li deposition and dissolution on foreign substrates, and reveals that SEIs could be more influential to Li dissolution and spatial integration of SEI shells on Li deposits is important to improving the reversibility of deposition and dissolution cycling.

Aiming to gain insight on the hydrogen storage properties of Mg-based alloys, partial hydrogenation and hydrogen pressure related de-/hydrogenation kinetics of Mg–Ni–La alloys have been investigated. The results indicate that the phase boundaries, such as Mg/Mg2Ni and Mg/Mg17La2, distributed within the eutectics can act as preferential nucleation sites for β-MgH2 and apparently promote the hydrogenation process. For bulk alloy, it is observed that the hydrogenation region gradually grows from the fine Mg–Ni–La eutectic to primary Mg region with the extension of reaction time. After high-energy ball milling, the nanocrystalline powders with crystallite size of 12∼20 nm exhibit ameliorated hydrogen absorption/desorption performance, which can absorb 2.58 wt% H2 at 368 K within 50 min and begin to desorb hydrogen from ∼508 K. On the other side, variation of hydrogen pressure induced driving force significantly affects the reaction kinetics. As the hydrogenation/dehydrogenation driving forces increase, the hydrogen absorption/desorption kinetics is markedly accelerated. The dehydrogenation mechanisms have also been revealed by fitting different theoretical kinetics models, which demonstrate that the rate-limiting steps change obviously with the variation of driving forces.

Black phosphorus (BP) is an emerging two-dimensional semiconductor material, which has interesting structural features and broad application prospects in the fields of optoelectronic devices, energy storage, and biomedicine. However, a large amount of evidence is still needed to clarify the potential mechanism for the synthesis of high-quality BP crystals in chemical vapor transport (CVT) reactions. In this work, High-purity BP crystal was synthesized by CVT method in amorphous Red Phosphorus (aRP), Sn and I2 system. We found that the synthesis of BP experienced three stages of structural transformation of aRP-P4-Hittorf’s Phosphorus (HP)-BP. First, the phase transition of aRP and P4 molecules was reversible in the sublimation stage; then, the P4 molecules were gradually transformed into the HP structure in the transportation and deposition stage; however, the nucleation of BP quickly inhibited the growth of HP and completed the phase transition quickly; Finally, the remaining P4 molecules were transformed into BP structure, which promoted the growth of BP crystals. This crystallization kinetics explained the nucleation mechanism during the formation of BP, and the competitive nucleation between HP and BP provided the possibility for the bottom-up preparation of BP nanobelts.

Metallic zinc has become one of the most potential anodes for aqueous zinc-ion batteries (ZIBs) due to its high capacity and safety. However, uneven Zn deposition and hydrogen evolution at zinc anode severely limit the development and commercialization of aqueous ZIBs. Here, we directly formed a uniform ridge-like ZnMoO4 layer on the Zn anode (denoted as Zn@ZnMoO4) within 20 s by chemical deposition. Due to its special structure and strong binding energy to Zn adatoms, the modified layer can induce uniform zinc nucleation and inhibit dendrite growth. In addition, ZnMoO4 can significantly increase the adsorption free energy of H adatoms (ΔG(H*)), suppressing the evolution of hydrogen. With this synergy effect, Zn@ZnMoO4 delivers strong hydrogen suppression capability that increases the hydrogen evolution overpotential from 27 mV to 137 mV, achieves exciting cycling stability for 10,000 cycles at a high current density of 10 mA cm−2. Meanwhile, the capacity retention rate of the Zn@ZnMoO4/α-MnO2 full battery reaches 87% after 1000 cycles under 1A g − 1.

The reactions of cerium in hydrogen mixed with different concentrations of CO2 were conducted by using a pressure-volume-temperature (PVT) method combined with an in situ hot-stage microscope. CO2 has a great suppression effect on the hydriding reaction of cerium. The existence of CO2 leads to longer induction time, less pitting, and much slower hydriding rate. It is found that the induction time of hydriding reaction grows exponentially as a function of CO2 concentrations. Besides, the nucleation and growth of hydride spots are also suppressed with increase of CO2 concentrations. Scanning electron microscopy (SEM) and in situ optical microscope measurements reveal that the hydride spots formed in H2-CO2 mixture have a prolate hemispherical morphology while the normal hydride spots formed in pure H2 show an oblate hemispherical morphology. Thermal desorption results indicate CO2 preferentially adsorbs on the active sites of CeO2 surface resulting in block of hydrogen dissociation, which is accountable for the observed hydriding inhibition phenomenon. Our studies provide new insights into the CO2 effect on the hydriding process of active metals.

Since recent research indicates that the addition of graphene increases the mechanical and biological properties of calcium phosphates simultaneously, graphene oxide (GO) was used in this research to enhance the properties of brushite cement. The main objective of this study is to investigate the mechanism of nucleation and growth of brushite crystals on GO sheets. Calcium nitrate tetrahydrate and diammonium hydrogenphosphate were used as calcium and phosphate precursors. The brushite chemical precipitation method on graphene sheets was used in this study and computer-assisted modeling was used to understand the process. The results of this study showed that the hybrid powders contained brushite and GO. Brushite crystals were grown after nucleation in proportion to the three main planes containing (020), (12 1 ¯ ), and (141). The final particles were plate shaped. The results of setting time tests showed that increasing the GO% decreases the setting time and this trend continues with an increasing amount of GO. The results of the mechanical evaluation showed that increasing the GO by up to 2% increased the mechanical properties and more than that decreased the mechanical properties.

The working fluid of the hydrogen recirculation ejector in proton exchange membrane fuel cell (PEMFC) systems is humid hydrogen containing water vapour. However, previous studies on the hydrogen recirculation ejector using computational fluid dynamics (CFD) were based on the single-phase flow model without considering the phase change of water vapour. In this study, the characteristics of the phase change and its effect on the ejector performance are analysed according to a two-phase CFD model. The model is established based on a non-equilibrium condensation phase change. The results show that the average deviation of the entrainment ratio predicted by a single-phase flow model is 25.8% compared with experiments involving a hydrogen recirculation ejector, which is higher than the 15.1% predicted by the two-phase flow model. It can be determined that droplet nucleation occurs at the junction of the primary and secondary flow, with the maximum nucleation rate reaching 4.0 × 1020 m−3s−1 at a primary flow pressure of 5.0 bar. The higher temperature, lower velocity, and higher pressure of the gas phase can be found in the mixing region due to condensation, resulting in a lower entrainment performance. The nucleation rate, droplet number, and liquid mass fraction increase remarkably with an increasing primary flow pressure. This study provides a meaningful reference for understanding phase change characteristics and two-phase flow behaviour in hydrogen recirculation ejectors for PEMFC systems.

The non-uniform aggregation of fast-diffused Li on an anode surface would aggravate its tip-effect-induced nucleation/growth, leading to the notorious dendrite growth in Li metal batteries (LMBs). Tuning the Li diffusion on the anode surface has been regarded previously as a mainstream method to induce its uniform deposition, while the diffusion of Li in the anode bulk is usually ignored. Here, conceptually different from the classic surface modification, we propose a molecular tunnelling strategy to construct atomic channels in graphite bulk, which enables the fast diffusion of superdense Li. Density functional theory calculations and ab initio molecular dynamics simulations prove that the bulk diffusion through atomic channels could become a new and dominating path. Its reversible and efficient diffusion has been further visualized by in situ transmission electron microscopy. As a result, when coupled with high-loading LiFePO4 cathodes (20 mg cm−2), a high areal capacity and 100% capacity retention are achieved over 370 cycles. Through this work a new strategy is developed based on the bulk-diffusion of superdense Li for dendrite-free LMBs, which can be pervasive in other high-performance energy storage systems.

Although lithium metal (Li) has been considered as the ideal anode material for next generation batteries, its practical applications are hindered by detrimental dendrite growth due to non-uniform Li deposition. It is reported that the substrate materials and their lattice mismatch have significant roles on Li nucleation. However, the defects such as dislocations resulted from the applied strain on substrate materials, have been seldomly investigated. Hence, strained copper current collectors (CuCCs) are used as the substrate to investigate the defects (mainly dislocations) on the nucleation and growth behaviors of Li. It is found that the variation of dislocation density and structure can significantly influence the nucleation behaviors of Li. The increase of dislocation density can effectively reduce the nucleation energy barrier and favors the uniform nucleation of Li. The lowered nucleation energy barrier and critical nuclei size promote the subsequent growth of Li. The subsequent growth of Li embryos on CuCCs with 5% strain becomes orderly and forms the compact Li thin film through intergranular fusion rather than the generation of dendrites via 1D growth. As anodes in both half and symmetric cells, the compact deposited Li layer exhibits high Coulombic efficiencies and long cycling stability indicating its great potential as a stable Li metal anode.

Lithium metal batteries are considered as high energy density battery systems with very promising prospects and have been widely studied. However, The uncontrollable plating/stripping behavior, infinite volume change and dendrites formation of lithium metal anode restrict the application. The uncontrolled nucleation of lithium caused by the nonuniform multi-physical field distributions, can lead to the undesirable lithium deposition. Herein, a graphene composite uniformly loaded with Ag nano-particles (Ag NPs) is prepared through a facile Gamma ray irradiation method and assembled into self-supported film with layered structure (Ag-rGO film). When such film is used as a lithium metal anode host, the uncontrolled deposition is converted into a highly nucleation-induced process. On one hand, the Ag NPs distributed between the interlayers of graphene can preferentially induce lithium nucleation and enable uniform deposition morphology of lithium between interlayers. On the other hand, the stable layered graphene structure can accommodate volume change, stabilize the interface between anode and electrolyte and inhibit dendrites formation. Therefore, the layered Ag-rGO film as anode host can reach a high Coulombic efficiency over 93.3% for 200 cycle (786 h) at a current density of 1 mA cm−2 for 2 mAh cm−2 in carbonate-based electrolyte. This work proposes a facile Gamma ray irradiation method to prepare metal/3D-skeleton structure as lithium anode host and demonstrates the potential to regulate the lithium metal deposition behaviors via manipulating the distribution of lithiophilic metal (e.g. Ag) in 3D frameworks. This may offer a practicable thinking for the subsequent design of the lithium metal anode.

Carbon quantum dots “CQDs” were investigated as photo-luminescent nanomaterials as it advantageous with nontoxicity to be alternative for metallic-nanomaterials in different purposes. Therefore, the presented report demonstrates an innovative strategy for industrialization of antimicrobial/fluorescent cotton textiles via exploitation of “CQDs”. Unique/novel infrared-assisted technique was currently investigated for clustering “CQDs” form carboxymethyl cellulose. The successive nucleation of “CQDs” (8.0 nm) was affirmed via infra-red, Raman spectroscopy, NMR, TEM and Zeta-potential analysis. The clustered “CQDs” showed antimicrobial and fluorescent characters. The minimal inhibition concentration for “CQDs” (100 mg/mL) against E. coli and C. albicans showed pathogenic reduction of 96% and 82%, respectively. Fluorescent emission spectra for “CQDs” showed two intense peaks at 415–445 nm. “CQDs” were loaded upon pristine and cationized cotton to prepare CQDs@cotton and CQDs@cationized cotton. While, their physical/mechanical properties (air and water vapor permeabilities, tensile strength and elongation %) and thermal stability (TGA & DTG analysis) were studied. The CQDs@cationized cotton exhibited excellent antimicrobial activity with good durability as after ten repretitive washings, inhibition zone diameter against E. coli, was diminished from 21.0 mm to 14.0 mm. The fluorescent emmision intensity was diminished from 741 to 287 after 10 washing cycles. The produced cotton fabrics could be safely used in the medical and military textiles.

Nanodiamonds (NDs) were prepared under ambient pressure by sublimation decomposition of silicon carbide in an intermediate frequency furnace for only 8 min. The synthesis proceeded in the temperature range of 2600-2800°C without any catalyst or highly active gas components (such as H2, alkane, and halogen). The conversion began at 2600°C and produced NDs with particle sizes in the range of 1-5 nm with a uniform particle shape and excellent dispersion. The linear reaction kinetics allowed for rapid transformation to any depth with reasonable control of the temperature. The linear rate constant (Kl) for the reaction at 2800°C was 37.5 mm/h, which is 31.2 times that of the reaction at 2600°C. The SiC sublimation decomposition produced carbon atoms that filled the SiC lattice vacancies or were combined with the suspended carbon chain bonds to form sp3 carbon, while the diffusion of amorphous carbon atoms promoted nucleation and growth of diamond. High-resolution transmission electron microscopy analysis indicated that the NDs were separated from the SiC matrix by break-off due to propagation of the reaction front. This SiC sublimation decomposition method is considered simple, fast, environmentally friendly and promising for industrial-scale production.

Cast multicrystalline silicon (mc-Si) requires high quality at low cost, while fully-melted seed-assisted growth has a reasonable utilization rate but urges better initial grain control. An electrophoretic deposited quartz nucleation layer is introduced to obtain a uniform and oriented nucleation layer. Carrier recombination characterization, including photoluminescence and carrier lifetime mapping, shows that the density of recombination-active structural defects is reduced due to better grain distribution. The average conversion efficiency values of silicon particle, sprayed quartz, and deposited quartz assisted wafers are 20.52%, 20.48%, and 20.68%, respectively Moreover, deposited quartz assisted mc-Si can obtain oriented grains, which offers a potential to apply alkaline texturing on mc-Si wafers.

Cadmium sulfide nanoparticles (CdS NPs) were synthesized by using cadmium acetate and thiourea as precursors and sodium oleate as the surfactant under different cadmium acetate concentrations in anhydrous ethanol. Cadmium (Cd) precursor concentration greatly affected the nucleation-growth of CdS NPs. In extremely dilute solution with a Cd precursor concentration of 0.1 mmol · L−1, an overlapped nucleation and growth corresponding to two pronounced absorption peaks at 310 nm and 350 nm, respectively, was observed. Unparalleled nucleation was dominant within very long reaction time until 10 hours. The nuclei and the resulting magic-sized CdS NPs may be used as seeds to prepare size and shape controllable nanoparticles. On the contrary, at a high Cd precursor concentration (5 mmol · L−1), nucleation and growth were separated. Only one first exciton absorption peak standing for the growth of regular CdS NPs appeared at 440 nm. Many techniques including transmission electron microscopy (TEM), X-ray powder diffraction (XRD), ultraviolet-visible (UV-Vis) absorption and photoluminescence (PL) spectrometers were applied to characterize the morphology, crystalline structure, and optical properties of CdS NPs.

Organic cathodes have emerged as promising candidate for sodium ions batteries (SIBs) because of their high theoretical capacity, molecular diversity, and sustainability. However, the inferior rate performance and poor cycle life still restrict their large-scale applications. Herein, a facile strategy for the synthesis of ultrathin quinone-rich polydopamine (PDA) coating which is tightly adhered on 3D porous carbon surface (PC-PDA-APS) is prepared through a superfast (∼1.5 h) heterogeneous nucleation process. Ammonium persulfate (APS) used as initiating agent can not only restrain the self-nucleation of dopamine, but also promote the transformation from bi-hydroxyl to bi-carbonyl with an ultra-high conversion rate up to 81%. Having benefited from the synergistic effect of inter-connective 3D carbon skeleton, ultrathin PDA coating, and ultrahigh quinone content, the PC-PDA-APS exhibits significantly high specific capacity (322 mA h g−1 at 0.1 A g−1), and excellent rate performance (102 mA h g−1 at 10 A g−1). More specially, the combination of DFT calculations and in-situ FTIR spectroscopy verifies the synergistic Na+ storage mechanisms of reversible enol reaction of C=O groups with Na+ and imine groups (R=N-R') with Na+. This research fundamentally provides a structural engineering method for remarkably improving the performance of sodium-organic cathode.

The ability to combine layers with high mechanical strength and additional physicochemical properties, such as biocompatibility, makes the use of multilayer coatings attractive for various applications. The transition from single layer to nanolaminate architecture can improve the mechanical performance of the coatings by increasing the number of interfaces and decreasing the modulation period of the layers. The microstructural study of the nanolaminate (Al0·5Ti0.5)N/ZrN coating with a modulation period λ of ≃ 20 nm was carried out using the TEM-HRTEM method. It was found that the coatings of (Al0·5Ti0.5)N/ZrN series consisted of two phases: the fcc-(Ti,Al)N solid solution obtained by isomorphic substitution of Ti atoms with Al ones in the TiN crystal lattice and the cubic ZrN phase. ZrN layers had a high texture structure with [111]-preferred growth texture and made a dominant effect on the nucleation and growth of (Al0·5Ti0.5)N layers. The epitaxial growth process was the most pronounced for fcc-(Ti,Al)N (111)||fcc-(ZrN) (111) and fcc-(Ti,Al)N (200)||fcc-(ZrN) (200) grains. Finally, the new coating demonstrated high biocompatibility, failure to toxicity and supported U2OS osteogenic cells proliferation within 7 days of cultivation.

Enabling highly reversible sodium (Na) metal anodes in a polymer electrolyte (PE) system is critical for realizing next-generation batteries with lower cost, higher energy, and improved safety. However, the uneven Na deposition and high Na/PE interphase resistance lead to poor reversibility and short cycle life of Na metal anodes. To tackle these problems, here a variety of metal nanoparticles (M-np, M = Al, Sn, In or Au) are deposited onto copper (Cu) foils to synthesize binder-free M-np@Cu substrates for Na plating/stripping. Notably, the Au-np@Cu substrate provides abundant preferential nucleation/growth sites, decreasing Na nucleation barrier and thus promoting uniform Na deposition. Accordingly, stable Na metal anodes are achieved with high reversible capacities, long cycle life, and high usage of Na. With the Au-np@Cu/Na anode and PE, the full cell using a commercial bulk sulfur cathode exhibits a reversible capacity of >400 mAh g−1 with near-100% Coulombic efficiency over 200 cycles.

Background Magnesium-loaded hydroxyapatite (Mg@HAp) is a potential biomaterial for bone healing application but has not been comprehensively synthesized yet. Methods In this study, we utilize phosphatidylcholine (PC)-assisted method for synthesizing Mg@HAp with controllable Mg amount from 1.44 to 10.64 wt%. It is proposed that the negatively charged phosphate functional group of PC could act on cations (i.e. Mg2+ or Ca2+), which provides stable nucleation for the formation of Mg@HAp. Significant findings By optimizing the synthesis conditions, we successfully prepared a Mg@HAp with a relatively low crystallinity which is similar to human bone structure, as evidenced by XRD measurement. The in vitro test of bone cells (MG-63) shows that the release of Mg2+ ions from Mg@HAp enhances cellular proliferation and differentiation. We believe the synthesized Mg@HAp would be a promising biomaterial in orthopedic applications.

Iron-chromium-aluminum (FeCrAl) alloys with different content of niobium (Nb)—0, 0.4 wt%, 0.8 wt%, and 1.2 wt%—were designed and prepared. All samples were then irradiated with 2.4 MeV Fe2+ ion to the dose of 1 and 15 displacements per atom (dpa) at 400 °C. The formations of dislocation loops induced by self-ion irradiation in these alloys were investigated by transmission electron microscopy (TEM). Nano-indentation tests were used to assess the hardness and irradiation hardening of samples. For the samples before irradiation, the (Fe, Cr)2(Nb, Mo) Laves phases density and the nano-indentation hardness increased with increasing Nb content of the samples. After irradiation to 1 and 15 dpa, both of a/2 and a dislocation loops were produced but no voids or αˊ phase were found in all samples. With increasing Nb content of the samples, the size of dislocation loops increased first and then decreased, while the total volume number density decreased and then increased. The fraction of a dislocation loops increased first and then decreased with increasing Nb content, and increased with increasing irradiation dose. Dislocation networks and the amorphization of the Laves phases were observed in the samples with irradiation dose of 15 dpa. Irradiation hardening of Nb free samples was two to four times that of Nb containing samples, and the irradiation hardening increased with increasing Nb content of Nb containing samples. The experimental results indicate that the increase of Nb content in FeCrAl alloys can increase the density of Laves phases, leading to the decrease of Mo content and increase of Cr content in the matrix. The competition between the two types of solutes affects the nucleation and growth of the dislocation loops.

Two-phase titanium-based alloys are widely used in aerospace and biomedical applications, and they are obtained through phase transformations between a low-temperature hexagonal closed-packed α-phase and a high-temperature body-centred cubic β-phase. Understanding how a new phase evolves from its parent phase is critical to controlling the transforming microstructures and thus material properties. Here, we report time-resolved experimental evidence, at sub-angstrom resolution, of a non-classically nucleated metastable phase that bridges the α-phase and the β-phase, in a technologically important titanium–molybdenum alloy. We observed a nanosized and chemically ordered superstructure in the α-phase matrix; its composition, chemical order and crystal structure are all found to be different from both the parent and the product phases, but instigating a vanishingly low energy barrier for the transformation into the β-phase. This latter phase transition can proceed instantly via vibrational switching when the molybdenum concentration in the superstructure exceeds a critical value. We expect that such a non-classical phase evolution mechanism is much more common than previously believed for solid-state transformations. A full kinetic pathway of a non-classical nucleation-induced phase transformation through metastable states is elucidated at sub-angstrom resolution in a technologically important titanium alloy.

Attention toward aqueous zinc-ion battery has soared recently due to its operation safety and environmental benignity. Nonetheless, dendrite formation and side reactions occurred at the anode side greatly hinder its practical application. Herein, we adopt direct plasma-enhanced chemical vapor deposition strategy to in situ grow N-doped carbon (NC) over commercial glass fiber separator targeting a highly stabilized Zn anode. The strong zincophilicity of such a new separator would reduce the nucleation overpotential of Zn and enhance the Zn-ion transference number, thereby alleviating side reactions. Symmetric cells equipped with NC-modified separator harvest a stable cycling for more than 1,100 h under 1 mA·cm−2/1 mAh·cm−2. With the assistance of NC, the depth of discharge of Zn anode reaches as high as 42.7%. When assembled into full cells, the zinc-ion battery based on NC-modified separator could maintain 79% of its initial capacity (251 mAh·g−1) at 5 A·g−1 after 1,000 cycles.

Fatigue damage to babbitt layers of plain bearings is often manifested during operation. The goal of the study is to develop a model for accumulation of the fatigue damage and destruction of antifriction materials and layers of plain bearings. A generalized fatigue diagram of tin-based babbitts including the main stages of fatigue damage and a diagram of the fatigue damage development in the antifriction layer of plain bearings are presented. The generalized model of V. V. Bolotin for damage accumulation and destruction is modified with regard to antifriction materials containing rather large structural elements. An explicit (direct) modeling of damage processes appeared possible for such materials. The model describes dissipated accumulation of microcracks (interpreted as destruction of the elements of the material structure), initiation and development of a system of short cracks, initiation and development of macro-cracks up to the limit state of the object. The model suggests discretization of the volume into sections with constant levels of complex stress state and discretization of the time axis into the intervals (blocks of loading cycles). The problem of identifying the parameters of a multistage model of the fatigue damage accumulation in the alloy is solved proceeding from the analysis of the results of testing babbitt specimens. We used the simplest optimization procedure, i.e., the method of deformable polyhedron. The parameters of the power function in the dependence of the rate of microdamage accumulation on the level of stresses are obtained. The parameters of the initiation and development of the crack system in the babbitt layer are obtained from the analysis of experimental results of studying steel-babbitt samples. The problem of calculating the durability of antifriction babbitt layers required the development of a new software. The program is examined by comparing calculated and experimental values of the durability of fatigue-tested bearing specimens forced against a rotating shaft by varying cyclic load. The calculated values of the durability match the experimental which confirms the performance of the calculated model.

Sufficient experimental evidence has suggested that polycyclic aromatic hydrocarbons are the building blocks of carbonaceous nanostructures in combustion and circumstellar envelops of carbon-rich stars, but their fundamental formation mechanisms remain elusive. By exploring the reaction kinetics of phenylacetylene with 1-naphthyl/4-phenanthryl radicals, we provide compelling theoretical and experimental evidence for a novel and self-consistent hydrogen-abstraction phenylacetylene-addition (HAPaA) mechanism. HAPaA operates efficiently at both low and high temperatures, leading to the formation, expansion, and nucleation of peri-condensed aromatic hydrocarbons (PCAHs), which are otherwise difficult to synthesis via traditional hydrogen-abstraction acetylene/vinylacetylene-addition pathways. The HAPaA mechanism can be generalized to other α-alkynyl PCAHs and thus provides an alternative covalent bond bridge for PCAH combination via an acetylene linker. The proposed HAPaA mechanism may contribute toward a comprehensive understanding of soot formation, carbonaceous nanomaterials synthesis, and the origin and evolution of carbon in our galaxy.

A copper terephthalate metal organic framework-anchored CoAl-layered double hydroxide nanocomposite [CoAl-LDH/Cu-(tpa) MOF] was synthesized by in situ nucleation and growth of crystalline Cu-(tpa) ...

In order to refine both primary and eutectic Si in the A390 aluminum alloy to improve the mechanical properties, a combined process of the serpentine pouring channel (SPC) and Sb-modifier was developed to prepare a semi-solid slurry for the rheological high pressure die casting (Rheo-HPDC). The results indicate that the refinement of primary Si particles (PSPs) is attributed to the chilling and self-stirring induced by the SPC. Antimony has a negligible effect on the size of the PSPs and plays an important role in the refinement of eutectic Si. The Sb-rich intermetallic compounds (i.e., AlSb and Mg3Sb2) cannot act as a heterogeneous nucleation site for the PSPs. The AlSb phase enclosed in the PSPs becomes the crack initiation of the PSPs. The refinement of primary and eutectic Si as well as the preparation temperature of semi-solid slurry (TPS) are the crucial reasons for improving the mechanical properties of Rheo-HPDC A390-xSb alloy. The optimal ultimate tensile strength (UTS) and elongation (El) are 257 ± 6 MPa and 0.52 ± 0.04%, respectively, for the Rheo-HPDC A390-0.3 wt.% Sb at TPS of 680 °C.

Metal-assisted chemical etching (MACE) of silicon is used in this study to fabricate silicon nanowire arrays (SiNWs) of different length. This method was modeled using gene expression programming (GEP), and GEP was optimized using genetic algorithms (GA). The length of SiNWs has been predicted as a function of parameters like Ag nucleation on Si and etching solution parameters. The SiNWs in the experimental test have a minimum length of 1 μm. According to FE-SEM images, SiNWs are uniformly shaped. It could be used to fabricate electrode materials for micro-supercapacitor.

We show that foreign second phase particles incorporated into the lithium metal-ceramic-electrolyte interface catalyze nucleation of voids, which, at first, lead to higher voltage and then to voltage collapse in constant current experiments. Voltage increases because voids grow the area-specific resistance. The collapse is caused by dendrites. Cell manufacture in high class clean room environments is recommended for the sake of reliability and increased performance.

In this study, the carbide precipitation at 925 °C in austenite (γ) of a 0.04C–1.5Mn–0.10Ti–0.39 W (wt%) low-carbon steel was investigated by stress relaxation (SR) high-resolution transmission electron microscopy and atom probe tomography. First-principles calculations were employed to reveal the precipitation mechanism. Results indicate that a high dispersion of W- and Fe-rich MC-type ultrafine carbides (

Rechargeable lithium metal batteries (LMBs) are faced with concerns of safety and short lifespan because of the uncontrollable growth of lithium (Li) dendrites. Natural biomolecules enriched with diverse polar groups are likely to have high lithiophilicity, showing the potential to suppress the dendrite growth. However, besides the chemical compositions, their structural diversities from nature induce notable impacts on the functions, which has not been studied yet. Here, through experiments and molecular simulations, we discover a natural “relief” for Li dendrites, zein protein, and successfully strengthen its dendrite-suppressing ability by tailoring its configurations to achieve long-life Li anodes. The “strong relief configuration” (SRC-Zein) is generated via drastically unfolding and opening the compact protein structure using a powerful denaturant. Modifying the separator by SRC-Zein results in excellent electrolyte wettability, higher ionic conductivity (2.0 mS/cm), and higher Li+ transference number (0.68), compared with the less unfolded protein. These important properties play the synergistical role in homogenizing the ion deposition and inhibiting the nucleation/growth of Li dendrites. As a result, the symmetrical Li/Li cell exhibits exceptional cycling stability for more than 1400 h at 2 mA/cm2. Furthermore, the half-cell with the SRC-Zein modified separator shows significant enhancement in capacity, cycle stability, and rate performance.

In the electro-deoxidation process, carbon parasitic reaction (CO32– + 4e– = C + 3O2–) usually occurs when using carbon materials as the anode, which leads to increase of the carbon content in the final metal and decrease of the current efficiency of the process. The aim of this work is to reduce the negative effect of carbon parasitic reaction on the electrolysis process by adjusting anode current density. The results indicate that lower graphite anode area can achieve higher current density, which is helpful to increase the nucleation site of CO2 bubbles. Most of CO2 would be released from the anode instead of dissolution in the molten CaCl2 and reacting with O2– to form CO32–, thus decreasing the carbon parasitic reaction of the process. Furthermore, the results of the compared experiments show that when the anode area decreases from 172.78 to 4.99 cm2, CO2 concentration in the released gases increases significantly, the carbon mass content in the final metal product decreased from 1.09% to 0.13%, and the current efficiency increased from 6.65% to 36.50%. This study determined a suitable anode current density range for reducing carbon parasitic reaction and provides a valuable reference for the selection of the anode in the electrolysis process.

The problem of utilizing substantial bamboo residual waste while also improving the quality of building composites was addressed by preparing bamboo scrap/magnesium oxychloride composites using bamboo scraps as a reinforcing material and magnesium oxychloride as a matrix. However, problems remain, such as poor interface compatibility and poor water resistance, which limit its application range. Herein, nano-silica (nSiO2) was found to build a crystal nucleus and a network structure in the composites, such that the bamboo scrap/magnesium oxychloride composites had higher mechanical properties and water resistance. In addition, the nSiO2 crystal nucleus structure promoted the composites hydration process, promoted the growth of the 5-phase crystals and the close arrangement of the cross, thereby improved composites strength. The nSiO2 build a network structure at composites interface, which improved the compatibility of composites interfaces, thus improving water resistance. At the same time, nSiO2 and the crystal nuclei adsorbed a portion of CO2 and CO, which had a certain hindering effect on the release of toxic gases in fire, and provided new ideas for fire safety protection. These results expanded the scope of application of building composites, which can be used in the fields of fireproof materials and building decoration materials, and provided a good solution for bamboo processing waste, thus making a certain contribution to green environmental protection.

Lithium (Li) metal is considered as one of the most promising anode materials to build next-generation high-energy–density batteries. Nonetheless, dendritic Li deposition has dramatically hindered the practical applications of Li metal batteries (LMBs). Uniformizing Li deposition is a prerequisite to achieve safe and practical LMBs. Herein, an underpotential deposition (UPD) process is first proposed to alter the kinetic and uniformity of Li deposition morphology. Based on the strong interaction between the Li adatoms and manganese (Mn) based substrate, a competition between the UPD and bulk Li deposition is observed, on which the predominance of the UPD scenario tends to uniformize Li nucleation and deposition by the surface coverage of Li monolayers at potentials that are more positive than the Nernst potential of Li metal. Inspired by this process, an advanced hybrid Mn-graphene oxide structure is developed for Li protection, not only enabling dendrite-free Li anodes for high-capacity and -current density cycling, but also improving the interfacial kinetic of Li metal anodes at subzero temperatures, showing potential applicability in low temperature conditions.