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This paper investigates two types of wafer arrangements, vertical and horizontal, in a multi-wafer atomic layer deposition (ALD) reactor. The growth rate of ALD deposited alumina thin film is characterized and compared experimentally and numerically. It's found that the wafer layout influences the deposition process significantly. Vertical multi-wafer arrangement is shown superior to the horizontal arrangement in terms of film deposition rate because of the enhanced collisions between precursor molecules and wafer surfaces in vertical arrangement. Studies using three-dimensional transient numerical model of fluid dynamics and surface reaction kinetics in multi-wafer batch ALD reveal the self-limiting details on the physical and chemical nature of ALD process. First, the deposition process is shown highly "self-limited": surface reactions in ALD are completely terminated once surface species conversion comes to the end. Second, deposition process is found under a joint influence of precursor concentration and surface site saturation status. Before deposition rate reaches its peak, the precursor concentration is dominant in determining the deposition rate, but it is largely confined by the available surface reactive sites after the peak. Position dependence of deposition rate as shown by both experiments and simulations is weak and negligible.

Development of high performance anode materials is of critical importance for advanced lithium-ion batteries. Herein, we report a novel 3D hybrid composed of well-dispersed Co 2 P nanoparticles embedded in N-doped carbon nanotubes grown on porous carbon polyhedral (Co 2 P/NCNTFs) as advanced electrode for lithium-ion batteries. The Co 2 P/NCNTF electrode is synthesized with a facile pyrolysis and phosphidation method derived from a cobalt-based zeolitic imidazolate framework. The resultant Co 2 P/NCNTFs hybrid demonstrates superior electrochemical performance in lithium-ion batteries, with a large discharge capacity of 906 mA h g −1 at 100 mA g −1 , excellent rate performance of 508 mA h g −1 at 6.4 A g −1 , high Coulombic efficiency of 99.4% after 300 cycles at 100 mA g −1 , and high cycling performance with a capacity retention of 94.7%, which is among the best obtained results for Co 2 P-based anode materials.

An electrochemically stable hybrid structure material consisting of porous silicon (Si) nanoparticles, carbon nanotubes (CNTs), and reduced graphene oxide (rGO) is developed as an anode material (Si/rGO/CNT) for full cell lithium-ion batteries (LIBs). In the developed hybrid material, the rGO provides a robust matrix with sufficient void space to accommodate the volume change of Si during lithiation/delithiation and a good electric contact. CNTs act as a mechanically stable and electrically conductive support to enhance the overall mechanical strength and conductivity. The developed Si/rGO/CNT composite anode has been first tested in half cell and then in full cell lithium-ion batteries. In half cell, the composite anode shows a high reversible capacity of 1100 mAh g−1 with good capacity retention over 500 cycles when cycled at 1 A g−1. In a full cell lithium-ion battery paired up with LiNi1/3Mn1/3Co1/3O2 (NMC) cathodes, the composite anode shows a specific charge capacity of 161.4 mAh g−1 and a discharge capacity of 152.8 mAh g−1, respectively, with a Coulombic efficiency of 94.7%.

Silicon nanowires (SiNWs) with three different average diameters of 90, 120, and 140 nm were synthesized by a metal-assisted chemical etching (MACE) method. Environmental sustainability of the MACE process was studied by investigating material consumptions, gas emissions, and silver nanoparticle concentrations in nitric acid solutions for 1 g of SiNWs and 1 kW h of lithium-ion battery (LIB) electrodes. It was found that the process for 90 nm SiNWs has the best sustainability performance compared with the other two processes. Specifically, in this study for 1 g of 90 nm SiNWs, 8.845 g of Si wafer is consumed, 1.09 g of H2 and 1.04 g of NO are produced, and 54.807 mg of Ag nanoparticles are found in the HNO3 solution. Additionally, for 1 kW h of LIB electrodes, the process for 90 nm SiNWs results in 1.943 kg of Si wafer consumption, 239.455 g of H2 and 239.455 g of NO emissions, and 12.040 g of Ag nanoparticles concentrations. By quantitatively investigating the material consumptions and emissions, this study assesses the sustainability performance of the MACE process for synthesizing SiNWs for use in LIBs, and thus it provides process data for the analysis and the development of sustainable production methods for SiNWs and similar anode materials for next-generation LIBs.

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The formation of a solid electrolyte interface (SEI) on a Li-ion battery electrode during usage cycling is a critical reason for battery capacity loss. In this paper, laser ablation technology is applied to remove SEI from a graphite electrode surface. Characterization methods including scanning electron microscopy, Raman microscopy, and Fourier transform infrared spectroscopy are used to study the structure and morphology changes of the SEI on the electrode surface. The results show that laser ablation can successfully remove the SEI, indicating a feasible method to clean the electrode surface.