Dramatic enhancement in energy harvesting for a narrow range of dimensions in piezoelectric nanostructures

Abstract
Recent work suggests that flexoelectricity causes significant enhancement of electromechanical coupling of nonuniformly strained piezoelectric and nonpiezoelectric nanostructures below a material-dependent length scale. In the present work, employing an atomistically informed dynamical continuum model that accounts for flexoelectricity, we argue that in a narrow range of geometric dimensions, piezoelectric nanostructures can dramatically enhance energy harvesting. Specifically, in the case of lead zirconate titanate
PZT material employed in the form of cantilever beams, our results indicate that the total harvested power peak value can increase by 100% around 21 nm beam thickness
under short circuit conditions and nearly a 200% increase may be achieved for specifically tailored cross-section shapes. The key
hereto undiscovered insight is that the striking enhancement in energy harvesting is predicted to rapidly diminish
compared to bulk both below and above a certain nanoscale structural length thus providing a rather stringent condition for the experimentalists.

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是滴，這篇PAPER寫出了在21奈米的厚度下，壓電材料所產生的效率會是最大的

有興趣的人，GOOGLE一下文章名稱就有了


FROM HERE
M. S. Majdoub, P. Sharma and T. Çağin, "Dramatic enhancement in energy harvesting for a narrow range of dimensions in piezoelectric nanostructures", PHYSICAL REVIEW B 78, 121407(R)(2008).