Abstract
| - Using extensive state-of-the-art experiments over a wide range of synthesis parameters, suchas the temperature and concentrations of different reactants, we establish qualitatively different growthkinetics for ZnO nanocrystals compared to all growth kinetics of semiconductor nanocrystals, includingZnO, discussed so far in the literature. The growth rate is shown to be strongly dependent on theconcentration of (OH)- in an intriguing nonmonotonic manner as well as on temperature and is almostinvariably much slower than well-known and generally accepted growth mechanisms based on a diffusion-controlled Ostwald ripening process or that expected in the surface reaction controlled regime. We showthat these qualitatively different results arise from the unexpected role played by a part of the reactants byinhibiting rather than facilitating the reaction; we explain this extraordinary result in terms of an effectivepassivating layer around the growing nanocrystals formed by a virtual capping shell of Na+ ions.
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