Importance of soft solution processing for advanced inorganic materials

Abstract

Based upon the analysis of materials cycling and processing on the earth, a thermodynamic concept for energetical and environmental problems has been proposed. It concludes that solution processing using aqueous solutions should be the most important processing even for advanced materials. According to this concept, energetical and environmental features of soft solution processing (SSP) are discussed in general, using also some particular examples, such as BaTiO3. Applications of the SSP are shown with special emphasis on hydrothermal and/or electrochemical synthesis of thin films and integration issues. Soft solution processing allows one to fabricate in aqueous solutions shaped/sized/oriented ceramics in only one step, without excess energies for firing/sintering or melting and without expensive equipment, providing an environmentally friendly route for the preparation of advanced ceramic materials.

Hydrothermal synthesis of yttrium and niobium co-doped anatase-type titania nanoparticles

“…The photocatalytic activity i.e., photodegradation amount of MB for the as-prepared anatase samples versus UVlight irradiation time is shown in Fig. 12 2 showed the same level of photocatalytic activity as that of pure TiO 2 . The decrease in the photocatalytic activity in the samples X ² 1.0 is partly due to the decrease in substantial TiO 2 content and decrease in the crystallinity of anatase in the samples, though it is not appropriate to mention the details of factors decreasing photocatalytic activity from only this experiment.…”

Nanofabrication of Metal Oxide Patterns Using Self-Assembled Monolayers

“…The fabrication of metal oxide thin films from solutions has been encouraged by the development of environment-friendly chemistry such as Green & sustainable chemistry [1][2][3][4][5][6] , Bioinspired materials chemistry 7 , Biomimetic materials chemistry 7 , Soft-solution processing [8][9][10] , Soft chemistry ("Chimie douce" in French) 11 , Liquid phase deposition 7,12 , Chemical bath deposition (CBD) 12,13 , Electroless deposition (ED) with catalyst 12,13 , Successive ion layer adsorption and reaction (SILAR) 12,13 , Sol-gel process 14,15 , Hydrothermal reaction 16 , Electrodeposition 17,18 and so on. Solution processing of metal oxides allows us to prepare metal oxide thin films on the surface of solids such as substrates, particles, and fibers.…”

Direct Fabrication of Patterned Functional Ceramic Films by Soft Solution Processing without Post-Firing

“…In order to address this problem, we must aim to minimize the total energy consumption during the whole life cycle of products, from mining and up-grading of raw materials, through production/fabrication, transportation, usage, and disposal to recycling. Only then will processes become more environmentally friendly [1][2][3].…”

“…SSP aims, based upon thermodynamic considerations, to fabricate shaped, sized and controlled advanced materials from aqueous solutions without excess heat and energy consumption and without using expensive equipment and precursors, preferably in a single step [1][2][3]. There has been considerable interest in processes where intersacial reactions, mostly at Sliquid/solid interfaces, are performed by self-assembling, templating, and/or self-organizing of species.…”