In view of the increasing applications of nanocatalysis in chemical transformations, this article illustrates recent advances on the use of nanocatalysts for an important reduction reaction, the hydrogenation of nitroaromatics to significant aminoaromatics with aqueous NaBH4 solution; the utility of mono- and multi-metal nanocatalysts with special emphasis on heterogeneous nanocatalysts are included. A progressive trend on the applicability of nanocatalysts is also incorporated with large scale application and their sustainable recyclization and reuse utilizing supported and magnetic nanocatalysts; representative methods for the synthesis of such reusable nanocatalysts are featured.

Department of Materials Science and Engineering Research Institute of Advanced Materials Seoul National University Seoul 08826 Republic of Korea

Electronic Materials Center Korea Institute of Science and Technology Seoul 136 791 Republic of Korea

Regional Center of Advanced Technologies and Materials Department of Physical Chemistry Faculty of Science Palacky University Šlechtitelů 27 783 71 Olomouc Czech Republic

Water Resources Recovery Branch Water Systems Division National Risk Management Research Laboratory US Environmental Protection Agency Cincinnati Ohio 45268 USA

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