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Owing to the high energy density of phase change materials, latent heat storage systems have been an effective strategy for the improvement of energy efficiency. The severe limitations of their extensive application are the potential leakage and low thermal conductivity. Herein, we developed a facile dual-encapsulation method to solve the abovementioned problems in the phase change composite composed of octadecanol, a high thermal/electrical conductive macroporous graphite foam and a thin waterborne polyurethane (WPU) film. After dual-encapsulation, the thermal conductivity of the composite was 20 times higher than that of pure phase change material (PCM) octadecanol. As a result, the composite exhibited a reduced supercooling degree and rapid thermal energy charging behaviors, as well as electro-to-heat conversion ability. This study gives a new perspective for the synergistic enhancement of both the thermal and electric conductivity of functional PCMs for thermal energy storage and conversion.

A simple electrochemical corrosion synthesis route using hot and concentrated alkaline aqueous solution is demonstrated for the first time to fabricate high yield crystalline magnetite mesocrystal microdisks without adding any organic additives. According to the results of time-dependent experiments, the self-assembly mechanism of mesocrystals is revealed as crystallization–dissolution–recrystallization. The mesocrystals with large sizes of 30 μm show hierarchical architectures. They are piled up with several thin layers and each layer is composed of small nanoparticles with an average size of 20 nm. Moreover, room temperature ferrimagnetic behavior with large coercivity value of 182.88 Oe (∼0.01829 T) is recorded.

LiNi1/3Co1/3Mn1/3O2 hollow nano-micro hierarchical microspheres (NCM-HS) are synthesized using MnCO3 both as a self-template and Mn source. The hollow microspheres with diameters of about 1 μm have walls about 250 nm thick, which are composed of approximately 100 nm primary nanoparticles. NCM-HS cathodes have an initial discharge capacity of 212 mA h g−1 at 0.1 C between 2.5 and 4.5 V. After 40 charge–discharge cycles, the capacity retention at 0.1 C is 85.1%. At higher rates, the reversible capacities of the NCM-HS cathodes are 208.9 (0.5 C), 204.8 (1 C), 180.7 (2 C), 155.7 (5 C) and 135.9 mA h g−1 (10 C). The high performances can be attributed to the distinctive hollow microspherical structures with the 100 nm building blocks, which could effectively reduce the path of Li ion diffusion, increase the contact area between electrodes and electrolyte and buffer the volume changes during the Li ion intercalation/deintercalation processes.

We synthesized unexplored activator-Fe doped silicon oxynitride microwires by a simple CVD method. This microwire can generate SPP when induced by photons/electrons. It exhibits three significant features, a stable emission peak, the ability to act as a plasmon nonlinear laser and displays mutual light beams interference. The absorption and external quantum efficiency of the Fe doped silicon oxynitride are 73.2% and 51.8%, respectively. Upon controlling the O/N ratio, the emission band can be tuned from 670 nm to 735 nm.

We have utilized the lattice mismatch between two adjacent nanocrystals in polycrystalline BFO ceramics to introduce a layer of highly strained BFO phase by taking advantage of crystal growth course. Therefore, a spin-valve like structure has been fabricated that consists of ferromagnetic phase (highly strained BFO phase)/antiferromagnetic phase (bulk BFO nanoparticles), without any substrates or alloy layers. BFO ceramics can present an exchange biasing effect ((|HEB|) ∼ 36 Oe) with an enhanced magnetic moment (Ms ∼ 0.11 μB Fe−1) and in addition saturated polarization (2Pr ∼ 57.4 μC cm−2) at room temperature. A low working electric field (Ec ∼ 4.8 kV cm−1) shows an advantage of low energy consumption in application. These results imply that there is potential for room temperature applications of single phase BFO with exchange biasing, enhanced magnetization and saturated polarization.

This paper reports on the non-traditional corrosion method for the synthesis of hematite mesocrystals in the size range of 30 μm. The results clearly show that the self-assembly of hematite mesocrystals were consisted of many small building units which were densely packed. The formation mechanism for hematite mesocrystals is proposed, which belongs to nonclassical crystallization. Ammonium chloride (NH4Cl), as a reagent in the reaction, has played a key role in the formation of hematite mesocrystals. The high coercivity of hematite mesocrystals of 4437.80 Oe was recorded. The origin of the large coercivity is also discussed. The size of the building units is the main reason, the anisotropies of the mesocrystals, defects, strain and exchange coupling are attributed to the enhancement of the large coercivity. All of the reasons for the explanation of the large coercivity can be attributed to the presence of N. The synthesis route is economical and environmentally friendly and is a promising way to fabricate other kinds of mesocrystals.