Preface

Metal nanocrystals in the size range of 1 to 100 nm have attracted extensive attention in the past decades due to their unusual properties and potential applications in many areas. In particular, metal clusters with a core size smaller than 2 nm exhibit unique physical and chemical properties that are significantly different from those of the corresponding large nanoparticles and molecular compounds. Such a size range represents a bridge between atoms/molecules and nanoparticles, and thus represents a fascinating multidisciplinary research area. Yet, because of the ultrasmall dimensions, development of effective protocols for the size-controlled synthesis has been a significant challenge in the studies of metal nanoclusters. In recent years, various effective strategies have been described in the literature for the synthesis of metal nanoclusters with a specific number of metal atoms and surface protecting ligands. The successful preparation of composition-determined metal clusters renders it possible to study their size- and composition-related properties. Significantly, with a size comparable to the Fermi wavelength of electrons and consequently the formation of discrete electronic energy levels, metal nanoclusters exhibit unprecedented optical and electronic properties, including size-dependent energy level structures, photoluminescence, and catalytic properties. Therefore, metal nanoclusters have been found to show promising applications in nanoelectronics, catalysis, biological and chemical sensing, molecular imaging, biological labeling, biomedicine, and so on.

This book highlights some recent progress in the synthesis, characterization, interfacial engineering and applications of metal nanoclusters. The contributors to this book consist of leading experts in this field. For organothiol-stabilized metal nanoclusters, the mechanism of cluster formation is of critical importance to achieve structure-controlled synthesis. Tong and co-workers first review and discuss the relevant chemistry involved in the two-phase synthesis of alklychalcogenolate-stabilized metal nanoparticles. As an important research field of metal nanoclusters, González and López-Quintela summarize the recently developed strategies and synthetic routes for the preparation of photoluminescent atomic quantum clusters. Up to now, the research in the field of metal nanocluster is mainly concentrated on gold and silver metals. In this book, several chapters focus on Au and Ag nanoclusters. Bigioni et al. report the magic-number silver nanoclusters, Xu and Suslick summarize the work on water-soluble fluorescent silver nanoclusters, Yang and Wang highlight biomolecule-protected silver nanoclusters, Xie et al. present the newly-developed synthetic strategies, and Pradeep et al. discuss in detail the preparation and application of noble metal clusters in protein templates. As an important application of metal nanoclusters, López-Quintela et al., Lu and Chen, and Tsukuda et al. review the catalytic properties of metal nanoclusters from different aspects. Wang and Ubaldo give a summary of the development of In Silico study of metal nanoclusters, which is helpful for the experimental syntheses and design of metal clusters. Zhou and Dong and Tanaka and Inouye highlight the biological applications of metal nanoclusters. Chen et al. review the recent advances in Janus nanoparticles through interfacial engineering. The editors express their deep appreciation to the authors for their support and contributions to the book.

This book will be a valuable reference for researchers in the general area of functional nanomaterials. It may also serve as a study guide for graduate students and senior undergraduate students who are interested in nanoscale materials chemistry and engineering.

Wei Chen

Shaowei Chen