Banca de QUALIFICAÇÃO: ANGEL ROBERTA OLIVEIRA DE SOUSA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : ANGEL ROBERTA OLIVEIRA DE SOUSA
DATE: 27/12/2019
TIME: 14:00
LOCAL: Sala de aulas do PPGCEM
TITLE:

Tuning the electrical conductivity of an N-type organic semiconductor through solution doping for thermoelectric applications

KEY WORDS:

Organic thermoelectric, organic doping, eletrical conductivity, N2200, dimer, (N-DMBI)2.

PAGES: 70
BIG AREA: Engenharias
AREA: Engenharia de Materiais e Metalúrgica
SUBÁREA: Materiais Não-Metálicos
SPECIALTY: Polímeros, Aplicações
SUMMARY:

Organic thermoelectric devices are composed by conductive polymers capable of converting thermal energy into electrical energy, and vice versa, through Seebeck and Peltier Effects. The organic doping is one of the most important approach used to improve and tune the electrical properties of polymers, especially n-type organic semiconductors, which are known to be the obstacle for the performance improvement of thermoelectric devices, since its performance lags behind when compared to the p-type semiconductor polymers and also due to their inefficient doping process. Systems using Poly{[N,N′-bis(2-octyldodecyl)-naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene) P(NDI2OD-T2), also known as N2200, as the host material, have been extensively investigated with 4-(1,3-Dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)phenyl)dimethylamine (N-DMBI), Mesitylene pentamethylcyclopentadienyl ruthenium dimer ((RuCp*mes)2), 4-(1,3-Dimethyl-2,3-dihydro-1H-benzoimidazol-2-yl)-N,N-diphenylaniline (DPBI), Tetrabutilamonium fluoride hydrate (TBAF), among others, but nothing has been reported about the N-DMBI dimer. Given this, the present work aimed to further study the effect of the concentration increases of (N-DMBI)2 in the N2200 matrix, mainly its impact in the electrical properties and in the morphology of the produced film. The characterizations used in this study were Visible ultraviolet spectroscopy (UV-vis), Electronic Paramagnetic Resonance Spectroscopy (EPR), Atomic Force Microscopy (AFM), Kelvin Probe Microscopy (KPM), two-point probe station and the Thin Film Analyzer (TFA) from Linseis. The last two characterizations were able to measure electrical conductivity of 8.64 . 10-3 S/cm for the 20%mol doped N2200-dimer sample, slightly higher than the benchmark 8.0 .10-3 S/cm with N2200-NDMBI system reported by Chabinyc in 2014. The Seebeck coefficient was approximately -110 uV/K. The AFM and the KPM helped to better understand the morphology and miscibility of the dopant material in the host

BANKING MEMBERS:
Interna - 2042234 - ANA PAULA CYSNE BARBOSA
Interno - 1298936 - ANTONIO EDUARDO MARTINELLI
Presidente - 1300987 - CARLOS ALBERTO PASKOCIMAS
Interno - 1350249 - RUBENS MARIBONDO DO NASCIMENTO