This paper shows the effect of the agglomeration control on the catalytic activity for oxygen evolution reaction (OER). In this study, (Ca_0.5Sr_0.5)RuO₃ (CSRO) catalyst was selected as the bi-functional catalyst for OER and oxygen reduction reaction (ORR). The sol-gel derived CSRO particle was mixed with the carbon nano-particle in the tetrahydrofuran (THF) based solution under the various pH condition to prepare the ink for the air electrode of rechargeable metal-air battery. The microstructure of the air electrode was designed by controlling the electrostatic repulsion force of the CSRO catalyst particles in the ink. As a result, the surface area of the air electrode increased with increasing the electrostatic repulsion force of the CSRO catalyst particle, resulting in the enhancement of the OER activity. From these results, we concluded that the agglomeration control of the catalyst particle in the ink is one of the key factors to enhance the catalytic activities of the electrocatalysts.

The “dry nanosuspension” granules and tablet, which could be spontaneously dispersed to submicrom-sized drug particles, were developed using wet milling and sequential fluidized-bed drying technique. Poorly water-soluble drug particles were beads-milled in the aqueous solution of dispersing agents using simple and general-purpose apparatus in laboratory. The milled nanosuspension was sprayed to the carrier particles of lactose in the fluidized-bed granulator to obtain the granulated product. It was found that the polymeric agent loaded as a milling promotor could play a role of binder to support the granulation and that the nano-sized drug particles were uniformly fixed on the surface of granulated particles. The resultant granules could re-construct the original drug nanosuspension within a few minutes in water, resulting in rapid dissolution behavior. Further, it was also found that the tablet prepared by compressing the granules kept their own rapid dispersible and release properties. The present technique via wet milling and fluidized-bed granulation/drying processes would be a novel dissolution-enhanced technology for poorly water-soluble drugs.

Microfluidic processes are capable of producing various types of microparticles with precisely controlled sizes, morphologies, and compositions. In this study we briefly introduce our recent progresses on the production of microparticles, utilizing the unique phenomena of formation and rapid dissolution of microdroplets in microfluidic channels. Water and a polar organic solvents are used either as the continuous or the dispersed phase, one of which contains the materials for particles (e.g., polymers). Because of the dissolution of the droplets, the particle materials are concentrated, forming microparticles with various morphologies and compositions. In this review, we explain the formation of such droplets in a non-equilibrium state and the production of polymeric, lipid, polysaccharide, protein, and carbon nanotube microparticles. Additionally, the application of the collagen microparticles to tissue engineering is presented.

In this manuscript, the advantages of flame spray pyrolysis (FSP) and recent progresses of FSP-made noble metal clusters supported catalysts are introduced. For noble metal catalysts, maximizing their performance while minimizing their use are the key challenge. To address it, FSP is a suitable technology as it can control the size of metal clusters from nano- to subnano-size and ultimately single atom size. The presence and the nature of such small clusters and single atoms were investigated using FTIR with a probing molecular and correlated to the photocatalytic performance. Also, a unique metal-support interaction induced in a flame and its role to increase the loading amount of noble metal clusters were discussed.

Many innovative processing of metal nanoparticle related material were developed by ultrasound and microwave reactor in solid-liquid system. Ultrasound and microwave reactor not only enhanced chemical reaction but also created novel chemical reaction. Metal oxide was used as eco-metal source in our processing. Solid-liquid (metal oxide–ethanol) system will be high concentration and high throughput processing. Realization of innovative nanomaterial fabrication enabled joining environment, low cost and high throughput by combining these reactor and metal oxide, solid-liquid system. This commentary explained reactor and nanomaterial processing problems and introduced the example of some metal nanoparticles related material processing by synergistic effects of solid-liquid system and ultrasound, microwave reactor.