Constructing unique mesoporous 2D Si nanostructures to shorten the lithium-ion diffusion pathway, facilitate interfacial charge transfer, and enlarge the electrode-electrolyte interface offers exciting opportunities in future high-performance lithium-ion batteries. However, simultaneous realization of 2D and mesoporous structures for Si material is quite difficult due to its non-van der Waals structure. Here, the coexistence of both mesoporous and 2D ultrathin nanosheets in the Si anodes and considerably high surface area (381.6 m g ) are successfully achieved by a scalable and cost-efficient method. After being encapsulated with the homogeneous carbon layer, the Si/C nanocomposite anodes achieve outstanding reversible capacity, high cycle stability, and excellent rate capability. In particular, the reversible capacity reaches 1072.2 mA h g at 4 A g even after 500 cycles. The obvious enhancements can be attributed to the synergistic effect between the unique 2D mesoporous nanostructure and carbon capsulation. Furthermore, full-cell evaluations indicate that the unique Si/C nanostructures have a great potential in the next-generation lithium-ion battery. These findings not only greatly improve the electrochemical performances of Si anode, but also shine some light on designing the unique nanomaterials for various energy devices.

Hydroxyapatite (HA) bioceramic scaffolds were fabricated by using digital light processing (DLP) based additive manufacturing. Key issues on the HA bioceramic scaffolds, including dispersion, DLP fabrication, sintering, mechanical properties, and biocompatibility were discussed in detail. Firstly, the effects of dispersant dosage, solid loading, and sintering temperature were studied. The optimal dispersant dosage, solid loading, and sintering temperature were 2 wt%, 50 vol%, and 1250 ℃, respectively. Then, the mechanical properties and biocompatibility of the HA bioceramic scaffolds were investigated. The DLP-prepared porous HA bioceramic scaffold was found to exhibit excellent mechanical properties and degradation behavior. From this study, DLP technique shows good potential for manufacturing HA bioceramic scaffolds.

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Two-dimensional amorphous MoS x (a-MoS x ) has been confirmed to be a highly active and economic electrocatalyst for hydrogen evolution reaction (HER). The development of its hybrid cocatalyst is envisioned to bestow more active sites with appropriate crystal engineering and modified electronic properties for enhancing catalytic performance. In this work, a composite cocatalyst comprising a-MoS x (x = 1.78) and well-ordered anodized TiO2 nanotube arrays (TNAs) is successfully developed through a facile electrodeposition route. The synergistic coupling of the unique vector charge transfer effect of TNAs and proliferation of active sites in a-MoS x derived from the space confinement effect and curved interface growth of TNAs lead to a significant enhancement of HER activity, compared to those of other forms of MoS2-based electrodes that have been previously reported. The MoS x /TNAs electrode exhibits the relatively small onset overpotential of 88 mV and presents an overpotential of 157 mV at 10 mA cm–2 HER current density. The composite electrodes also show an excellent stability with no performance degradation after undergoing 1000 times successive linear sweep voltammetry. The deposition of a-MoS x onto the curved sidewall in a confined space of TNAs is demonstrated to be an effective method to induce the growth of a-MoS x , leading to an enhanced catalytic activity toward HER.

Nanostructure engineering has been extensively applied to ZnO in an effort to improve its performance in thermoelectric material, solar cell, and nanogenerator applications. Nano-structured ZnO bulks are limited by their inherently low mobility caused by the high density of grain boundaries and interfaces. In this study, a hybrid micro/nano structure composed of nearly coherent grain boundaries with a low misorientation degree among the nanograins was successfully fabricated in Zn 1Àx Al x O (x ¼ 0, 0.01, 0.02, 0.03, 0.04 mol) bulks via hydrothermal synthesis and spark plasma sintering. Despite the large amount of nanograin boundaries and interfaces in the resulting material, a high carrier mobility value (50.7 cm 2 V À1 s À1 ) was obtained in the x ¼ 0.2 sampleclose to the level shown by ZnO single crystals and far higher than that of its ordinary nano-structured counterparts (<15 cm 2 V À1 s À1 ). A reduced thermal conductivity value of 2.1 W m À1 K À1 at 1073 K was also obtained in the micro/nano-structured x ¼ 0.02 bulk due to extremely effective scattering at boundaries and interfaces also present in the nano-structured counterparts. After the simultaneous optimization of both electrical and thermal transport properties, the micro/nanostructured x ¼ 0.02 sample showed a high ZT value (up to 0.36) at 1073 K. The proposed micro/nanostructure may also be applicable to other thermoelectric materials for further ZT enhancement.

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