Quantum size effects

Rossetti R, Nakahara S and Brus L E 1983 Quantum size effects In the redox potentials, resonance Raman spectra and electronic spectra of CdS crystallites In aqueous solution J. Chem. Phys. 79 1086... 

Quantum efficiencies Quantum efficiency Quantum electronics Quantum fluids Quantum mechanics Quantum size effect Quantumwell... 

Band gap engineetring confined hetetrostruciutres. When the thickness of a crystalline film is comparable with the de Broglie wavelength, the conduction and valence bands will break into subbands and as the thickness increases, the Fermi energy of the electrons oscillates. This leads to the so-called quantum size effects, which had been precociously predicted in Russia by Lifshitz and Kosevich (1953). A piece of semiconductor which is very small in one, two or three dimensions - a confined structure - is called a quantum well, quantum wire or quantum dot, respectively, and much fundamental physics research has been devoted to these in the last two decades. However, the world of MSE only became involved when several quantum wells were combined into what is now termed a heterostructure. 

D. Schmicker, T. Hibma, K. A. Edwards, P. B. Howes, J. E. MacDonald, M. A. James, M. Breeman, G. T. Barkema. Low-temperature growth of thin Pb layers and the quantum size effect. J Phys Condens Matt 9 969, 1997. 

Gorer S, Hodes G (1994) Quantum size effects in the study of chemical solution deposition mechanisms of semiconductor films. J Phys Chem 98 5338-5346... 

Hodes G, Albu-Yaron A, Decker F, Motisuke P (1987) Three-dimensional quantum-size effect in chemically deposited cadmium selenide films. Phys Rev B 36 4215-4222... 

Thin film coatings of nanocrystalline semiconductors, as collections of quantum dots (QD or Q-dot) attached to a solid surface, resemble in many ways semiconductor colloids dispersed in a liquid or solid phase and can be considered as a subsection of the latter category. The first 3D quantum size effect, on small Agl and CdS colloids, was observed and correctly explained, back in 1967 [109]. However, systematic studies in this field only began in the 1980s. 

Zhou, H.S., Honma, 1., Komiyama, H. and Haus, J.W. (1994) Controlled synthesis and quantum-size effect in gold-coated nanoparticles. Physical Review B - Condensed Matter, 50, 12052-12057. 

Semiconductor nanoparticles have been intensively studied because of their properties of quantum size effects [54]. A number of synthetic techniques have been reported and their characteristics have been studied by various spectroscopic methods [55, 56]. However, magnetic field effects (MFEs) on the photoelectrochemical properties of semiconductor nanocrystals had not until now been reported. 

Bimetallic nanoparticles (including monometallic ones) have attracted a great interest in scientific research and industrial applications, owing to their unique large sur-face-to-volume ratios and quantum-size effects [1,2,5,182]. Since industrial catalysts usually work on the surface of metals, the metal nanoparticles, which possess much larger surface area per unit volume or weight of metal than the bulk metal, have been considered as promising materials for catalysis. 

Main obstacle in identifying quantum-size effects as a reason for structure sensitivity stems from the difficult discrimination from geometric influences the latter will be discussed in the next paragraph. 

The rapid development of nanotechnology has revolutionized scientific developments in recent decades [1]. The synthesis, characterization, and application of functionalized nanoparticles are currently a very active field of research [2], Due to the size limitation of metal nanoparticles, they show very unique properties, which are called nano-size effect or quantum-size effect , which is different from those of both bulk metals and metal atoms. Such specific properties are usually dominated by the atoms located on the surface. In nanoparticles systems, the number of atoms located on the surface of the particles increases tremendously with decreasing of the particle diameter [3]. 

Lemire C, Meyer R, Shaikhutdinov S, Freund HJ. 2004. Do quantum size effects control CO adsorption on gold nanoparticles Angew Chem Int Ed 43 118-121. 

Small gold clusters (<100 atoms) have become the subject of interest because of their use as building blocks of nanoscale devices and because of their quantum-size effects and novel properties such as photoluminescence, magnetism, and optical activity [427]. 

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