Ni–P coatings on carbon steel were plated by a mechanically assisted electroplating technique, which combines the conventional electroplating technique with mechanical ball-rolling. The mechanical ...ball-rolling was conducted by vibrating the sample being plated with glass balls on it. For comparison, the conventional Ni–P electroplating technique without mechanical ball-rolling was also used to deposit Ni–P coatings under the same coating conditions as those adopted in the mechanically assisted electroplating. The experimental results show that the Ni–P coatings electroplated with mechanical assistance were smoother in surface, thinner in thickness, harder in hardness, more positive in corrosion potential, and greater in polarization resistance in comparison with the Ni–P coatings electroplated without mechanical assistance. The mechanical ball-rolling made the Ni–P coatings crystallized in-situ during the coating process, thereby avoiding crystallization-induced cracking, which was observed during the crystallization of the amorphous Ni–P coatings electroplated without mechanical assistance. A simple phase transformation model explains qualitatively the Ni–P in-situ crystallization during the mechanically assisted electroplating.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Display omitted
•A facile and controllable preparation method was adopted.•The detailed mechanism of hydrogenation process was elucidated.•The prepared electrocatalyst exhibits outstanding catalytic ...activity.•DFT calculations further verify the underlying mechanisms of catalytic performance.
Exploration of high-efficiency non-noble-metal-based electrocatalysts towards Hydrogen evolution reaction (HER) is critical for water electrolysis. In this work, we adopt a facile hydrothermal deposition plus hydrogen reduction strategy to fabricate self-supported Co@CoO core/shell nanowire arrays as a high-performance electrocatalyst for HER. The Co@CoO nanowire arrays are firmly anchored on the nickel foam substrate, forming an integrated electrode with excellent stability. The formation mechanism of the unique Co@CoO core/shell nanowire arrays is also explored. By virtue of the superior intrinsic catalytic activity of CoO shell and excellent electrical conductivity of Co core, the Co@CoO electrode exhibits significantly promoted catalytic activity for HER with an ultra-low overpotential (76 mV at 10 mA cm-2) in alkaline solution, which is superior to almost all the reported CoO-based electrocatalysts. Moreover, the Co@CoO electrode also yields superior long-term durability without any significant performance degradation. DFT calculations further verify the underlying mechanisms. Our proposed optimization strategy sheds light on the development of high activity earth-abundant-metal-based electrocatalyst for hydrogen evolution.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Ti incorporated amorphous carbon (a-C) films with variant Ti contents were prepared by the unbalanced magnetron sputtering process. Scanning electron microscopy, ultraviolet Raman spectroscopy, X-ray ...photoelectron spectroscopy and transmission electron microscopy were used to characterize the microstructure of a-C films. The hardness and lubricated tribological properties were assessed using nanoindentation and ball-on-disk tribometer. As the Ti content in a-C films increases from 0 to 15.2
at.%, the
sp
3 volume fraction, the internal stress and the hardness of the films decreases gradually, while the disorder of
sp
2 bond increases. The electrochemical tests reveal that the a-C films with lower than 1.5
at.% Ti possess good corrosion resistance in Hanks’ solution, while the a-C film with 15.2
at.% Ti is susceptible to crevice corrosion. The reduced friction of the a-C films is due to the
sp
2 bonded film surface and boundary lubrication of the Hanks’ solution. The a-C film with 3.1
at.% Ti exhibits the best wear resistance in Hanks’ solution among the studied films.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Thermochemical Energy Storage
In article number 2315529, Gang Xiao and co‐workers essentially provide an innovative insight into the development of metal oxides that are both sinter‐resistant and ...highly reactive. Changing the surface properties promotes the formation of porous structure, and changing its crystal structure introduces vacancies to accelerate oxygen diffusion. The constructed oxygen vacancy‐rich porous Cu2MgO3/Mg0.78Cu0.22O composite retains 99.9% and 97.1% reactivity after 3000 cycles.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
High‐temperature thermochemical energy storage based on metal oxides is the key technology to reducing the levelized costs of electricity of the next‐generation concentrated solar power plants. ...CuO/Cu2O has wide availability and high energy density, but severe sintering leads to low reactivity. In this study, an innovative approach to modulate the oxygen vacancy content to change the surface properties and crystal structure to enhance the sintering resistance and redox reversibility is proposed. The re‐oxidation degree is increased from 46% to 99%, and the energy release rate is increased by 3.5 times. It remains 99.9% reduction and 97.1% oxidation activity after 3000 cycles, which is very valuable for engineering applications. Cu2MgO3 and Mg0.78Cu0.22O are prone to form oxygen vacancies, which promotes the formation of porous structures. Mg0.78Cu0.22O helps Cu2MgO3/CuO/Cu2O deliver more O through the surface. Mg0.78Cu0.22O is firmly and uniformly dispersed on the CuO/Cu2O surface after long cycling. They have a large binding energy, more charge transfer and enhanced bond energy at the interface. The mechanism of composite in increasing the sintering temperature and long‐term reaction stability is revealed from experimental and theoretical calculations, which provides a new idea for the rational design of thermochemical energy storage materials.
Severe sintering of metal oxides at high temperatures leads to short cycle life. An innovative approach is proposed. Change the surface properties to form the porous structure. Vacancies are introduced into the crystal to accelerate oxygen diffusion. Cu2MgO3/Mg0.78Cu0.22O composite remains 99.9 % and 97.1 % redox activity after 3000 cycles. The reaction mechanism is revealed by DFT and experiment.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract High‐temperature thermochemical energy storage based on metal oxides is the key technology to reducing the levelized costs of electricity of the next‐generation concentrated solar power ...plants. CuO/Cu 2 O has wide availability and high energy density, but severe sintering leads to low reactivity. In this study, an innovative approach to modulate the oxygen vacancy content to change the surface properties and crystal structure to enhance the sintering resistance and redox reversibility is proposed. The re‐oxidation degree is increased from 46% to 99%, and the energy release rate is increased by 3.5 times. It remains 99.9% reduction and 97.1% oxidation activity after 3000 cycles, which is very valuable for engineering applications. Cu 2 MgO 3 and Mg 0.78 Cu 0.22 O are prone to form oxygen vacancies, which promotes the formation of porous structures. Mg0 .78 Cu 0.22 O helps Cu 2 MgO 3 /CuO/Cu 2 O deliver more O through the surface. Mg 0.78 Cu 0.22 O is firmly and uniformly dispersed on the CuO/Cu 2 O surface after long cycling. They have a large binding energy, more charge transfer and enhanced bond energy at the interface. The mechanism of composite in increasing the sintering temperature and long‐term reaction stability is revealed from experimental and theoretical calculations, which provides a new idea for the rational design of thermochemical energy storage materials.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Concentrated solar power plant needs to be equipped with large-scale high-temperature heat storage module.Metal oxides can store and release heat through reversible redox reaction.Manganese oxides is ...non-toxic and cheap,showing great potential for applying in solar power plant,but it displays poor reversibility.Here,a manganese-based oxides with high reversibility by deep eutectic solvent（DES） ionic thermal synthesis was proposed,and effects of synthesis parameters and iron doping on heat storage performance were studied.MnCO3,as the raw material,was used to produce manganese oxides by ionic thermal decomposition at high temperature and released CO2,which could also form abundant pore structure,providing great channels for oxygen transmission and diffusionfor redox.Although this Mn2O3 synthesis method showed better reactivity than commercial Mn2O3,its oxidation rate was low.It is worth noting that oxidation rate of manganese iron oxide doped with 20% Fe,synthesized at 150 ℃,was fast.Its heat storage density reached 300.66 J/g,and reversibility of the reaction was the best,which could realize long-term stable cycle.Our results demonstrated that ionic thermal synthesis can increase the lattice oxygen ratio in manganese oxides,promoting migration of oxygen vacancies,and further improving reversibility and cyclic stability.
SnO2 has been extensively studied as an anode material for sodium-ion batteries, which, however, has long been subjected to poor conductivity and large volume expansion accompanied with an ...unsatisfactory electrochemical performance. Here, novel interlaced SnO2 nanoflakes are synthesized directly on a carbon cloth collector via hydrothermal and annealing treatment and then coated with polypyrrole (PPy) via electrodeposition. The as-prepared flexible SnO2@PPy on the carbon cloth exhibits a high initial capacity of 1172.1 mAh g–1 and an outstanding cycling stability with 85% capacity retention after 300 cycles at 0.1 A g–1, which can be contributed to the interlaced SnO2 nanoflakes as well as the coating of PPy. This result shows promising potential for construction of an electrode in high-performance energy storage fields.
Full text
Available for:
IJS, KILJ, NUK, PNG, UL, UM
Due to the high theoretical capacity and low reduction potential, metallic lithium is a promising anode material for the next generation of high‐energy‐density batteries. However, the dynamic Li ...plating/stripping process can easily destroy the unstable solid electrolyte interphase (SEI) and cause dendrite growth. Here, an artificial lithium sulfide nanoparticle composed SEI layer with superior stability and high ionic conductivity is designed by a spray quenching method. The artificial SEI layer on Li surface can effectively minimize the side reactions and suppress Li dendrite growth, and the metal electrode delivers stable cycling for 500 cycles in the symmetrical cell with carbonate electrolyte. Moreover, when this SEI‐modified Li anode is coupled with a LiFePO4 cathode, the full cell shows promoted cycling stability and rate capability. This work provides a broadly applicable and facile strategy to address the intrinsic issues of lithium metal anodes.
An artificial lithium sulfide nanoparticles (LSNP) composed solid electrolyte interphase (SEI) layer with superior stability and high ionic conductivity is prepared via a facile spray quenching method. This artificial SEI layer on Li surface could effectively minimize the side reactions and suppress Li dendrite growth. Thus, the LSNP layer‐protected anodes showed superior cycling performance both in the symmetrical cells and full cells.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
