The solution synthetic method can produce large quantities of silicon nanowires (SiNWs) for various applications, such as energy storage, texturing and composites materials, etc. However, solution-grown SiNWs exhibit very low conductivity compared to chemical vapor deposition (CVD)-grown SiNWs due to their poor crystallinity or reaction byproducts such as insulating polysiliane or polyphenylsilane. Here, we report the large-scale synthesis of phosphorus-hyperdoped Si nanowires (PH-SiNWs) with atomic ratios of the P content ranging from 1 to 2 atom % via the tin­(Sn)-seeded supercritical fluid–liquid–solid (SFLS) through the use of red P nanoparticles as dopant precursors. The resistivity of PH-SiNWs is 4.3 × 10–3 Ω·m, which is about 6 orders of magnitude lower than bulk silicon (Si) (1.86 × 103 Ω·m) and about 3 orders of magnitude lower than intrinsic SiNWs (1.19 Ω·m). PH-SiNWs can be assembled on fabrics used as active materials for lithium-ion batteries, and combined with carbon nanotube fabric as current collectors, the bilayer fabrics can be used as freestanding independent lithium-ion battery anodes without the need for binders and additive. The PH-SiNWs/carbon nanotube (CNT) bilayer fabric anode reaches 820 mAh g–1 after 1000 cycles at a charge/discharge rate of 2 A g–1, whereas the intrinsic SiNWs/CNT bilayer fabric only sustains its performance at the first 20 cycles. The PH-SiNWs/CNT bilayer fabric anode shows the first example of a solution-grown Si nanowire anode with a 1000-cycle life. The ex situ transmission electron microscopy (TEM) image shows that an evolved PH-SiNWs nanopore structure was formed after the cycle, whereas the intrinsic SiNWs anodes did not develop holes. This result can be attributed to the uniform doping of P in the Si nanowire, which enables the formation of nanopores for rapid lithium-ion transport tunnels.

To eliminate surface defects and improve the quality of molded parts, increasing the mold temperature is one of the solutions. Using high mold temperature can eliminate weld lines, reduce molding pressure, residual stress, clamping force and improve part surface quality. However, with the increasing of mold temperature, the cycle time will also be increased. Hence, people have paid the attention to mold temperature control technologies. Among them, the variotherm molding technologies, including Rapid Heat Cycle Molding (RHCM), Induction Heating Molding (IHM), and Electricity Heating Mold (E-mold), are some effective methods. Although those variotherm technologies have been proposed, how does the external or internal heating source affect the injection molding process and the final product? The true function and the efficiency study of each technology still remain vague. Hence, in this paper, we have systematically conducted various technologies, including Conventional Injection Molding (CIM), RHCM, IHM, and Emold by using true 3D transient cool technology. Through the inside mechanism investigation from time to time, the functions and the heating-cooling efficiency for each technology can be visualized. Finally, experimental study and verification of IHM is also performed.

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At present, greenhouses are used to grow a variety of crops around the world. However, with the change of climate, the increasingly harsh weather makes it more and more disadvantageous for people to work inside, and plants are difficult to grow. Previous research has illustrated that radiative cooling can be realized by using certain nonmetal oxide particles created for emission in an infrared atmospheric transparency window, which is an environmentally friendly cooling method due to reducing energy consumption. Polyethylene (PE)-based formulations with a UV stabilizer and nonmetal oxide particles (NOP) were first granulated and then formed a monolayer film by co-injection molding. The experimental results show that due to passive radiative cooling, under the environmental conditions of 35 °C, and only considering the natural convection heat transfer, the net cooling power of the greenhouse film developed in this study is 28 W·m−2 higher than that of the conventional PE film. The temperature inside the simulated greenhouse cladded with the new greenhouse covering was on average 2.2 °C less than that of the greenhouse with the conventional PE film.

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