Ferroelectric and photovoltaic properties of transition metal doped Pb(Zr0.14Ti0.56Ni0.30)O3-δ thin films

Shalini Kumari,J F Scott,R S Katiyar,Nora Ortega,Ashok Kumar

doi:10.1063/1.4868380

Abstract

We report nearly single phase Pb(Zr0.14Ti0.56Ni0.30)O3-δ (PZTNi30) ferroelectric having large remanent polarization (15–30 μC/cm2), 0.3–0.4 V open circuit voltage (VOC), reduced band gap (direct 3.4 eV, and indirect 2.9 eV), large ON and OFF photo current ratio, and the fast decay time. Reasonably good photo current density (1–5 μA/cm2) was obtained without gate bias voltage which significantly increased with large bias field. Ferroelectric polarization dictates the polarity of VOC and direction of short circuit current (ISC), a step forward towards the realization of noncentrosymmetric ferroelectric material sensitive to visible light.

Highlights

Ferroelectric semiconductors and their bandgap engineering represent the most fascinating research area since the discovery of ferroelectricity and related phenomenon.[1,2] Recently it has been experimentally observed that solid-solution of potassium-niobate and barium-nickel-niobate perovskite ferroelectrics possess immense potential for photovoltaic (PV) applications with reduced band gap and moderate quantum efficiency.[3]
We report nearly single phase Pb(Zr0.14Ti0.56Ni0.30)O3-δ (PZTNi30) ferroelectric having large remanent polarization (15–30 μC/cm2), 0.3–0.4 V open circuit voltage (VOC), reduced band gap, large ON and OFF photo current ratio, and the fast decay time
Ferroelectric polarization dictates the polarity of VOC and direction of short circuit current (ISC), a step forward towards the realization of noncentrosymmetric ferroelectric material sensitive to visible light

Summary

INTRODUCTION

Ferroelectric semiconductors and their bandgap engineering represent the most fascinating research area since the discovery of ferroelectricity and related phenomenon.[1,2] Recently it has been experimentally observed that solid-solution of potassium-niobate and barium-nickel-niobate perovskite ferroelectrics possess immense potential for photovoltaic (PV) applications with reduced band gap and moderate quantum efficiency.[3]. A long-standing challenge in solid state physics is the tailoring of bandgap of ferroelectric host matrix with transition metal ions at B-site, which in turn keeps the polarization intact with an enhancement of the bulk photovoltaic (PV) effect.[4,5,6,7] As we know in general, organic and other semiconconductor based PV cells require p-n junctions for the creation of photo-induced charge carriers, and the limitation of these devices is that it cannot produce open circuit voltage (VOC) above the band gap of the materials. Photo current switching dynamics and transient current behavior are discussed

EXPERIMENTAL DETAILS

RESULTS AND DISCUSSION

CONCLUSIONS