A series of nitrogen-containing micropore-donimated materials, porous triazine-based frameworks (PTFs), are constructed through the structural evolution of a 2D microporous covalent triazine-based framework. The PTFs feature predictable and controllable nitrogen doping and pore structures, which serve as a model-like system to more deeply understand the heteroatom effect and micropore effect in ionic liquid-based supercapacitors. The experimental results reveal that the nitrogen doping can enhance the supercapacitor performance mainly through affecting the relative permittivity of the electrode materials. Although microspores' contribution is not as obvious as the doped nitrogen, the great performances of the micropore-dominated PTF suggest that micropore-dominated materials still have great potential in ionic liquid-based supercapacitors.

The nanostructuring of silicon (Si) has recently received great attention, as it holds potential to deal with the dramatic volume change of Si and thus improve lithium storage performance. Unfortunately, such transformative materials design principle has generally been plagued by the relatively low tap density of Si and hence mediocre volumetric capacity (and also volumetric energy density) of the battery. Here, we propose and demonstrate an electrode consisting of a textured silicon@graphitic carbon nanowire array. Such a unique electrode structure is designed based on a nanoscale system engineering strategy. The resultant electrode prototype exhibits unprecedented lithium storage performance, especially in terms of volumetric capacity, without the expense of compromising other components of the battery. The fabrication method is simple and scalable, providing new avenues for the rational engineering of Si-based electrodes simultaneously at the individual materials unit scale and the materials ensemble scale.

Tin-core/carbon-sheath coaxial nanocables directly integrated into a reduced graphene oxide (RGO) surface are constructed by a new strategy involving a RGO-mediated procedure. The as-synthesized nanocables, with uniform diameter and high aspect ratio, are versatile and exhibit excellent lithium storage properties, as revealed by electrochemical evaluation.

A bottom-up method is used to construct novel metal-free catalysts for deeper study of oxygen reduction reaction (ORR) catalysis. Through controlling the structural evolution of a 2D covalent triazine-based framework, the conductivity, nitrogen configurations, and multidoping structures of the as-prepared catalysts can be easily tuned, which makes a great platform for both studying the mechanisms of the ORR and optimizing the performances of the metal-free catalysts.

We propose a novel material/electrode design formula and develop an engineered self-supporting electrode configuration, namely, silicon nanoparticle impregnated assemblies of templated carbon-bridged oriented graphene. We have demonstrated their use as binder-free lithium-ion battery anodes with exceptional lithium storage performances, simultaneously attaining high gravimetric capacity (1390 mAh g(-1) at 2 A g(-1) with respect to the total electrode weight), high volumetric capacity (1807 mAh cm(-3) that is more than three times that of graphite anodes), remarkable rate capability (900 mAh g(-1) at 8 A g(-1)), excellent cyclic stability (0.025% decay per cycle over 200 cycles), and competing areal capacity (as high as 4 and 6 mAh cm(-2) at 15 and 3 mA cm(-2), respectively). Such combined level of performance is attributed to the templated carbon bridged oriented graphene assemblies involved. This engineered graphene bulk assemblies not only create a robust bicontinuous network for rapid transport of both electrons and lithium ions throughout the electrode even at high material mass loading but also allow achieving a substantially high material tap density (1.3 g cm(-3)). Coupled with a simple and flexible fabrication protocol as well as practically scalable raw materials (e.g., silicon nanoparticles and graphene oxide), the material/electrode design developed would propagate new and viable battery material/electrode design principles and opportunities for energy storage systems with high-energy and high-power characteristics.

The aim of this study was to explore the application of computer-aided design and rapid prototyping (CAD/RP) for removable partial denture (RPD) frameworks and evaluate the fitness of the technique for clinical application. Materials and Methods: Three-dimensional (3D) images of dentition defects were obtained using a lab scanner. The RPD frameworks were designed using commercial dental software and manufactured using selective laser melting (SLM). A total of 15 cases of RPD prostheses were selected, wherein each patient received two types of RPD frameworks, prepared by CAD/RP and investment casting. Primary evaluation of the CAD/RP framework was performed by visual inspection. The gap between the occlusal rest and the relevant rest seat was then replaced using silicone, and the specimens were observed and measured. Paired t test was used to compare the average thickness and distributed thickness between the CAD/RP and investment casting frameworks. Analysis of variance test was used to compare the difference in thickness among different zones. Results: The RPD framework was designed and directly manufactured using the SLM technique. CAD/ RP frameworks may meet the clinical requirements with satisfactory retention and stability and no undesired rotation. Although the average gap between the occlusal rest and the corresponding rest seat of the CAD/RP frameworks was slightly larger than that of the investment casting frameworks (P < .05), it was acceptable for clinical application. Conclusion: RPD frameworks can be designed and fabricated directly using digital techniques with acceptable results in clinical application.

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