Recent advancement in the plasma spray processing for the production of nanomaterials for the next-generation lithium-ion batteries has been reviewed. Towards the carbon neutral goal, EV shift has been accelerated and the demand of the associated battery materials is expected to grow exponentially. Silicon is a promising candidate for high density anode but it has to be structured at the nano-meter length scale to attain both its high theoretical high capacity and better cycle stability because of its inherent electrochemical difficulties. Yet such nanomaterials are to be produced at high throughputs to meet the huge demand from the evergrowing battery market. To respond to these requirements, plasma spray can be the potential production approach. In fact, using low cost powder sources, a variety of namonaterials ranging from nanometal epitaxially attached nanoparticles to silicon nanorod have been produced at fast rates via the control of co-condensation during rapid cooling of high temperature silicon vapor. The cells using these nanomaterials have exhibited appreciable improvement in the battery cycle properties, underlining the potential of the plasma spray for the production route for the next generation storage.

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  We fabricated nanostructured Ge films using Ar and He radio-frequency magnetron plasma sputtering deposition. Monodisperse amorphous Ge nanoparticles of 30-50 nm size were arranged without aggregation in the high-gas-pressure range of 500 Torr. The Ge film porosity was as high as 15-30%. We tested the charge/discharge cycle performance of Li-ion batteries with nanostructured Ge and GeSn anodes. The Ge anode with a dispersed arrangement of nanoparticles showed a Li-storage capacity of 565 mAh/g after the 60th cycle. The capacity retention was markedly improved by the addition of 3 at% Sn in Ge anode. The GeSn anode （3 at% Sn） achieved a higher capacity of 1128 mAh/g after 60 cycles with 92% capacity retention. Precise control of the nano-morphology by a single step procedure using low temperature plasma is effective for stable cycling of high-capacity Ge anodes.

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  Developments of hydrogen production via thermal plasma processing for the last several decades were reviewed. Hydrocarbon pyrolysis by thermal plasma is one of the most profitable methods to produce hydrogen energy with useful carbon materials. High decomposition rate of hydrocarbon can be easily achieved by high temperature of thermal plasmas. Commercial scale plasma methane pyrolysis process has already been demonstrated with high yield of hydrogen and high-value carbon. Understandings of fundamental phenomena in hydrocarbon pyrolysis in thermal plasma processing will expand its profitability with higher energy efficiency.

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  The induction thermal plasma （ITP） process can synthesize nanoparticles of the order of 50-100 nm from the gas phase using its high-temperature reaction field. In order to obtain a permanent magnet with high properties, especially high coercivity, the fine grain size of about 100 nm is favorable. Fortunately, the nanoparticle size that the ITP process can prepare is optimal for unlocking the potential of permanent magnet compounds. Therefore, in this paper, we introduce the fabrication process of permanent magnet compounds, rare earth （R）-transition metals （TM）, currently reported, and describe the synthesis of R-TM nanoparticles by the ITP process, which we have been working on recently. Numerical calculation of nanoparticle formation is also included, and the results of considering nanoparticles obtained from both experiments and calculations are also described. Finally, the future development of this ITP process is also discussed.

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 Carbon dioxide reduction is one of the key technologies for achieving a sustainable society. In this study, plasma catalysis were used to hydrogenate carbon dioxide to produce methane. Plasma catalysis have attracted attention in recent years as a technology promoting a reaction at lower temperatures by various synergistic effects between plasma and catalysts. In this study, molecular sieve with a pore diameter of 3 Å was used as a catalyst and its role was investigated. The results showed that: 1. molecular and atomic adsorption functions of molecular sieves are useful to inhibit reverse reactions; 2. the influence of molecular sieves becomes stronger at higher pressures, resulting in higher methane production; 3. energetic reactive particles derived from hydrogen deactivate molecular sieves; 4. molecules adsorbed on molecular sieve can be recycled by hydrogen plasma irradiation.

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