Impact Of Cross Linking Chain Of N,N’-bis(napthalen-|-y|)-N,N’-bis(phenyl)-benzidine On Temperature dependent Transport Properties

¹Academy of Scientific and Innovative Research (AcSIR), CSIR-National Physical Laboratory Campus,Dr. K. S. Krishnan Road, New Delhi-110012, India

²CSIR-Network of Institutes for Solar Energy, CSIR-National Physical Laboratory, Dr. K. S. Krishnan Road, New Delhi-110012, India

Adv. Mater. Lett., 2016, 7 (10), pp 783-789

DOI: 10.5185/amlett.2016.6305

Publication Date (Web): Aug 01, 2016

Copyright © IAAM-VBRI Press

E-mail:sumanck@nplindia.org

Abstract

The impact of cross linking chain of N, N’-bis (napthalen-|-y|)-N, N’-bis(phenyl)-benzidine (NPB) was studied for opto-electrical properties having focus on temperature dependent transport properties. The Spiro structured NPB compound is closed in itself and the thin film surface roughness is less in comparison to NTNPB compounds. Both absorptions and photoluminence shows a shift of 10 nm towards higher wavelength in case of cross linked spiro structured compound. The mobility calculated in SCLC region for NT and Spiro NPB was 1.32×10^-7 and 3.3x10^-7 cm² V^-1s^-1, respectively. Both the compounds show single relaxations and can be modeled as an RC equivalent circuits. The dc conductivity for both the compounds was explained by Mott’s VRH models showing 3D transport mechanism. The hopping distance for NT and Spiro NPB compounds is 0.8 and 0.5 nm, respectively. The hopping conduction process can be explained clearly using correlated barrier hopping model. The cross linking of the compounds shows two orders of less density of states.

Keywords

Cross linking, thin film, impedance, hopping, mott&rsquo,s temperature, conductivity.