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arXiv · 1803.06656

Optical Property Study of Charge Compensated (Si, Na) Co-doped ZnO

Tulika Srivastava·Gaurav Bajpai·Gyanendra Rathore·Prashant Mishra·Shun Wei Liu·Sajal Biring·Somaditya Sen
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Abstract

ZnO is co-doped with Na+ and Si4+ in the ratio 2:1. The ratio was intentionally chosen so that net valence state of dopant theoretically matches that of host. This is to avoid dependence in the amount of oxygen vacancies/interstitials arising out of cationic valence state of the dopant. With such a combination, modifications in structural and optical properties do not depend on excess or deficit of the dopant charge state. For lower doping, Na+ ions behave as interstitial sites which enhance strain, lattice disorder and thereby creating defects. Formation of interstitial defects leads to reduction in bandgap energy and produce orange-red luminescence. For higher doping, Na+ starts substituting at Zn2+ site which helps in reducing strain and lattice disorder and thereby increases bandgap. Inspite of presence of Si4+ with higher charge, there is a gradual increase in oxygen vacancies due to lattice disorder.

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Tulika Srivastava, Gaurav Bajpai, Gyanendra Rathore, Prashant Mishra, Shun Wei Liu, Sajal Biring, Somaditya Sen. 2018-03-18. Optical Property Study of Charge Compensated (Si, Na) Co-doped ZnO. https://arxiv.org/abs/1803.06656

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