Nanostructured Lead Sulphide Depositions by AACVD Technique Using Bis(Isobutyldithiophosphinato)Lead(II) Complex as Single Source Precursor and Its Impedance Study.

Sadia Iram,Effat Sitara,Syeda Arooj Fatima,Syeda Aqsa Batool Bukhari,Azhar Mahmood,Rubina Shaheen,Mohammad Azad Malik

doi:10.3390/nano10081438

Abstract

This communication reports the synthesis of bis(diisobutyldithiophosphinato)lead(II) complex and its subsequent application as a single source precursor for the nanostructured deposition of lead sulphide semiconductors and its impedance to explore its scope in the field of electronics. Synthesized complex was characterized by microelemental analysis, nuclear magnetic resonance spectroscopy, infrared spectroscopy and thermogravimetric analysis. This complex was decomposed using the aerosol-assisted chemical vapour deposition technique at different temperatures to grow PbS nanostructures on glass substrates. These nanostructures were analyzed by XRD, SEM, TEM and EDX methods. Impedance spectroscopic measurements were performed for PbS in the frequency range of 40 to 6 MHz at room temperature. In a complex impedance plane plot, two relaxation processes were exhibited due to grains and grain boundaries contribution. A high value of dielectric constant was observed at low frequencies, which was explained on the basis of Koops phenomenological model and Maxwell–Wagner type polarization. Frequency-dependent AC conductivity results were compliant with Jonscher power law, while capacitance–voltage loop had a butterfly shape. These impedance spectroscopic results have corroborated the ferroelectric nature of the resultant PbS nanodeposition.

Highlights

IntroductionLead sulfide belongs to the chalcogenides semiconductors family, having a direct bulk band gap of 0.41 eV at room temperature [1]
Lead chalcogenides (PbX, X = S, Se, Te) are important semiconductor materials with narrow direct band gaps and some unique properties
Lead sulfide belongs to the chalcogenides semiconductors family, having a direct bulk band gap of 0.41 eV at room temperature [1]

Summary

Introduction

Lead sulfide belongs to the chalcogenides semiconductors family, having a direct bulk band gap of 0.41 eV at room temperature [1] This narrow band gap widens its application in photovoltaic cells [2], infrared detectors [3], thermoelectrics [4], dielectrics [5], gas sensing [6], biosensing [7] and photocatalytic applications [8]. A simple hydrothermal synthesis of single-crystalline cubic shaped PbS nanostructures and their photoconductivity and dielectric studies was performed by Sakthivel et al [15]. This provided evidence of polarization effects and transport properties of the charge carriers. It was observed that DC conductivity, capacitance, photocurrent, carrier’s concentration, mobility and drift velocity increased with the increase of thickness

Methods

Results

Conclusion