Thermally Control of Crystal Size and Bandgap

With Tth and being taken into consideration, Eq. (14.26) evolves into the form describing the dependent of the critical size  

This relation indicates that the crystal size is dominated by the term (Ta — 7) ,)/ [0.3rm(oo)] grain grows as Ta rises when Tin- The grain radius K is hence controllable by tuning the T.  

The inset in Fig. 14.10 shows the SEM micrograph of spontaneous grain growth at different temperatures. Both the crystal size and the bandgap agree with the BOLS expectation on the dependence of the physical properties. 

A simplified model to calculate the surface-to-volume atomic ratio dependent cohesive energy of nanotaystals. J. Phy.-Condens. Matter 16(36), L401— L405 (2004) 

The particle size dependence of cohesive energy of metallic nanoparticles. Chem. Phys. Lett. 372(5-6), 632-634 (2003) 

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