A Computational Study on the Variation of Bandgap Due to Native Defects in Non-Stoichiometric NiO and Pd, Pt Doping in Stoichiometric NiO

Condensed Matter

Borra, Vamsi¹  Mossayebi, Faramarz²  Itapu, Srikanth³ 

[1] Department of Applied Engineering and Technology, California University of Pennsylvania, California, PA 15419, USA;Department of Electrical and Computer Engineering, Youngstown State University, Youngstown, OH 44555, USA;Department of Electronics and Communication Engineering, CVR College of Engineering, Hyderabad 501510, India

关键词: b;    gap;    dopants;    nickel oxide;    palladium;    platinum;   

DOI  :  10.3390/condmat3040046

学科分类：凝聚态物理

来源: mdpi

【 摘 要 】

This paper presents a computational study of non-stoichiometric nickel oxide in a 64-cell NiO system to model and validate localized heating effects due to nanosecond laser irradiation. Variation in the Bandgap of NiO is studied as a function of varying concentrations of native defects, ranging from 0 to 25%. It is observed that there is a slight increase in the bandgap from 3.80 eV for stoichiometric NiO to 3.86 eV for Ni-rich NiO and to 3.95 eV for O-rich NiO. It is hence deduced that the experimental laser irradiation leads to simultaneous reduction of Ni2+ ions and the oxidation of NiO as the number of laser pulses increase. As well, a detailed study on the effects of doping nickel family elements, i.e., palladium (Pd) and platinum (Pt), in stoichiometric NiO is presented. A bandgap decrease from 3.8 eV for pure NiO to 2.5 eV for Pd-doping and 2.0 eV for Pt-doping for varying doping concentrations ranging from 0–25% Pd, Pt, respectively, is observed.

【 授权许可】

CC BY