Elucidations on the Effect of Lanthanum Doping in ZnO Towards Enhanced Performance Nanogenerators

  • Pandey Rajagopalan
  • Pramila Jakhar
  • I. A. PalaniEmail author
  • Vipul Singh
  • Sang Jae KimEmail author
Regular Paper


Energy harvesting using semiconducting piezoelectric materials is one of the key areas of current research due to its high biocompatibility, low impedance, and high temperature workable range. In this work, we have optimized the doping of Lanthanum in ZnO towards the realization of enhanced output nanogenerator. We have varied the percentage of lanthanum (0, 1, 2.5, 5 and 7.5%) in the ZnO and systematically studied the piezoelectric response of each device. The piezoelectric output improved three to fourfolds by the incorporation of Lanthanum above 2.5%. The voltage response was further escalated by the controlled annealing in an oxygen environment. The doped and annealed device show eight to ninefolds improved output (~ 13.5 V) compared to the intrinsic device (~ 1.6 V). Material properties were investigated thoroughly along with the piezoelectric using various characterization tools. The device show a high maximum power density (~ 2.5 mW/m2) and was used to charge several commercial capacitors. Finally, the device was demonstrated to work in intruder-safety alarm system application as low-cost device.


Piezoelectric energy Zinc oxide Doping Sensor 



Zinc oxide




Indium tin oxide


Polyethylene terephthalate


Polyvinyl alcohol



List of Symbols


Shape factor


Wavelength of X-ray


Crystallite size


Braggs diffraction angle


Peak to peak voltage


Active area of the device


Load resistance



The author Pandey R is grateful to Research Instrument Center, JNU Jeju for providing characterization facilities. Pandey R. would further like to thank the (MHRD), India, for providing the Teaching Assistantship (TA). Pandey R is also Thankful to Indo Korea Research Internship by DST, India and NRF, Korea. Pandey R is thankful to Prof Kim Sang Jae for IKRI. Pandey R is grateful to Prof P M Shirage, Dr Prateek bhojane, Ms Lichhavi Sinha, Mr Aayush Gupta and Mr. S S Mani Prabhu for helping and improving in the content of the manuscript. A part of the research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (2019R1A2C3009747, 2018R1A4A1025998).

Compliance with Ethical Standards

Conflict of interest

On behalf of all authors, the corresponding author states that there is no conflict of interest.

Supplementary material

40684_2019_151_MOESM1_ESM.mp4 (2.1 mb)
Supplementary material 1 (MP4 2195 kb)


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Copyright information

© Korean Society for Precision Engineering 2019

Authors and Affiliations

  1. 1.Mechatronics and Instrumentation Lab, Discipline of Metallurgy Engineering and Materials ScienceIndian Institute of Technology IndoreIndoreIndia
  2. 2.Molecular and Nano-electronics Research Group (MNRG), Discipline of Electrical EngineeringIndian Institute of Technology IndoreIndoreIndia
  3. 3.Mechatronics and Instrumentation Lab, Discipline of Mechanical EngineeringIndian Institute of Technology IndoreIndoreIndia
  4. 4.Nano Materials and Systems Lab, Department of Mechatronics EngineeringJeju National UniversityJejuSouth Korea

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