The lithium storage properties of graphene nanosheet (GNS) materials as high capacity anode materials for rechargeable lithium secondary batteries (LIB) were investigated. Graphite is a practical anode material used for LIB, because of its capability for reversible lithium ion intercalation in the layered crystals, and the structural similarities of GNS to graphite may provide another type of intercalation anode compound. While the accommodation of lithium in these layered compounds is influenced by the layer spacing between the graphene nanosheets, control of the intergraphene sheet distance through interacting molecules such as carbon nanotubes (CNT) or fullerenes (C60) might be crucial for enhancement of the storage capacity. The specific capacity of GNS was found to be 540 mAh/g, which is much larger than that of graphite, and this was increased up to 730 mAh/g and 784 mAh/g, respectively, by the incorporation of macromolecules of CNT and C60 to the GNS.

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Self-assembled functional molecules in mesostructured materials (MM) are synthesized directly either by coassembly of dye-bound surfactant of ferrocenyl TMA with silicate or by Pc (phthalocyanine) molecules doped within C 16 TMA micelles assembled with oxides framework such as vanadia (VO x ), MoO 3 , WO 3 , and SiO 2 to produce Pc-doped mesostructured materials. The process provides well-organized molecular doped mesostructured materials by a direct and simple procedure.

Blending a certain proportion of basalt fiber into concrete improves the toughness of concrete, which prevents cracking and avoids the brittle behaviors. In this paper, the compressive, tensile, and flexural tests of concrete with different basalt fiber contents were carried out. Then the test phenomena, failure modes, and mechanical properties were compared and analyzed to derive the relationship between the basalt fiber contents and mechanical properties. The toughness and crack resistance performance of basalt fiber reinforced concrete were evaluated by the fracture energy, advanced toughness parameters, and characteristic length proposed by Hillerborg. The correlation coefficient of basalt fiber was introduced to establish the calculation formula for mechanical properties of basalt fiber reinforced concrete. The results indicated that basalt fiber significantly improved the toughness and crack resistance performance of concrete. The enhancing effect of the basalt fiber on the compressive strength of concrete is lower than that of tensile strength and flexural strength. Moreover, the improvement effect was the highest with the basalt fiber content was 0.3% and 0.4%.

Self-ordered and structure-controlled transparent films of tin-modified mesoporous silica (Sn/Si ratio of 0.5-3%) were first prepared using a molecule surfactant template method employing spin coating. A surface photovoltage (SPV) NO(2) gas sensor was then fabricated using these self-ordered tin-modified mesoporous silica thin films based on a metal-insulator-semiconductor structure. Highly sensitive tin-modified mesoporous silica was obtained that could detect NO(2) gas concentrations of as low as 300 ppb at room temperature. The detection mechanism for NO(2) is believed to involve both the surface area, which contributes to the change in dielectric constant, and the amount of tin incorporated, which contributes to the change in charge. It was found that, in this SPV sensor, the optimal Sn/Si ratio of 0.5% delivered record-high sensing performance.

Solid-state control of the thermal conductivity of materials is of exceptional interest for novel devices such as thermal diodes and switches. Here, we demonstrate the ability to continuously tune the thermal conductivity of nanoscale films of La0.5Sr0.5CoO3-δ (LSCO) by a factor of over 5, via a room-temperature electrolyte-gate-induced non-volatile topotactic phase transformation from perovskite (with δ ≈ 0.1) to an oxygen-vacancy-ordered brownmillerite phase (with δ = 0.5), accompanied by a metal-insulator transition. Combining time-domain thermoreflectance and electronic transport measurements, model analyses based on molecular dynamics and Boltzmann transport equation, and structural characterization by X-ray diffraction, we uncover and deconvolve the effects of these transitions on heat carriers, including electrons and lattice vibrations. The wide-range continuous tunability of LSCO thermal conductivity enabled by low-voltage (below 4 V) room-temperature electrolyte gating opens the door to non-volatile dynamic control of thermal transport in perovskite-based functional materials, for thermal regulation and management in device applications.