Highly fine, dispersive, and active catalysts are essential for lowering the operating temperature of MgH2, a promising high-capacity material for solid-state hydrogen storage. In this work, ultrafine Ni nanoparticles (2–6 nm) are synthesized from the precursor nickel acetylacetonate (C10H14NiO4) on the surface of MgH2 by H2 plasma reduction process, followed by further ball milling. The obtained composite could rapidly release more than 6.5 wt % H within 10 min at 275 °C. Even at a low temperature of 225 °C, up to 6 wt % H could be desorbed. The MgH2–Ni composite also exhibits excellent low-temperature hydrogenation kinetics and almost no capacity degradation over nine hydrogenation/dehydrogenation cycles. The significant improvement in the hydrogen-storage properties is attributed to the in situ formation of ultrafine and stable Mg2NiH0.3 nanocrystals during cycling. This work provides a convenient approach to synthesize ultrafine metal nanoparticles for catalytic applications in the field of high energy storage density hydride materials.

Anodes made of molybdenum trioxide (MoO3) suffer from insufficient conductivity and low catalytic reactivity. Here, we demonstrate that by using a dealloying method, we were able to fabricate anode of Ti-doped MoO3 (Ti-MoO3), which exhibits high catalytic reactivity, along with enhanced rate performance and cycling stability. We found that after doping, interestingly, the Ti-MoO3 forms nanosheets and assembles into a micrometer-sized flowerlike morphology with enhanced interlayer distance. The density functional theory result has further concluded that the band gap of the Ti-doped anode has been reduced significantly, thus greatly enhancing the electronic conductivity. As a result, the structure maintains stability during the Li+ intercalation/deintercalation processes, which enhances the cycling stability and rate capability. This engineering strategy and one-step synthesis route opens up a new pathway in the design of anode materials.

As non-precious-metal catalysts for the hydrogen evolution reaction (HER), molybdenum carbides have attracted extensive attention in recent years. Molybdenum carbides usually require high synthesis temperatures (>700 °C), which leads to a high cost. In this study, we report a controllable synthesis of heterophase molybdenum carbides (MoC/Mo2C) using a simple ball milling method without external thermal input. The as-obtained MoC/Mo2C catalysts exhibit excellent HER electrocatalytic activity and durability at all pH conditions in comparison with MoC or Mo2C alone. The interface of MoC/Mo2C formed in situ is the key factor in improving the electrocatalytic activity. This fabrication method is cheap and effective in generating heterophase interfaces, which can be employed in many other fields where interface engineering is needed.

Tin monosulfide (SnS), showing great prospect for lithium-ion batteries (LIBs), is restricted by its low conductivity and severe volume change during cycling. Moreover, severe agglomeration of SnS grains is ineluctable in the synthesis processes. Herein, the composite with both amorphous carbon and reduced graphene oxide (rGO) has been considered as an effective strategy to solve these problems. We have constructed a layered-structure of SnS particles anchored on rGO sheets with Ndoped carbon coated on the grain surface. This dual-carbon structure successfully achieves uniform dispersion and restricted growth of grains, which is demonstrated by XRD, SEM, and TEM analyses. Besides, the introduction of N-doped carbon coating and rGO supporting effectively mitigates drastic volume change as well as enables excellent electronic conductivity of SnS during discharge/charge processes. Therefore, as anode for LIBs, the N-doped carbon coated SnS/rGO composite (SnS@N-C/rGO) shows outstanding rate capability and cycling performance. At 0.1 A g −1 , it delivers a high initial reversible capacity of 1068.9 mAh g −1 . Even at 1.0 A g −1 , it also shows a high initial reversible capacity of 885.3 mAh g −1 and maintains 824 mAh g −1 after 550 cycles. Thus, the dual-carbon modification is a feasible strategy to promote the electrochemical properties of SnS and contribute alternative anodes for LIBs.

Silicon has emerged as a competitive candidate for hydrolytic hydrogen production due to its high theoretical hydrogen yield, low cost, and on-demand availability. However, the hydrolysis reaction is extremely restrained by passivated SiO2, including the original one on the Si surface and the generated one during hydrolysis, and almost no hydrogen is produced in pure water. Herein, the original SiO2 surface has been effectively removed by milling micro-Si mixed with a small amount of Li metal and NaCl. An artificial soluble interface on Si has been established containing Li2SiO3, Li, and NaCl. Once micro-Si is placed into water, fresh Si surface can be exposed and a weak LiOH solution can be generated due to the fast dissolution of the interface layer, resulting in the rapid liberation of hydrogen gas. Accordingly, the modified micro-Si displays a significantly enhanced hydrogen production in pure water at 30 °C (1213 mL g–1 H2 within 3.0 h), which is 2.0 and 4.7 times higher than that observed for ball-milled Si and raw Si in 0.06 M LiOH solution, respectively. In addition, it also exhibited an outstanding operation compatibility for practical uses. This work has proposed a green, effective, and scalable strategy to promote hydrogen production from the hydrolysis of Si-based systems.