@article{ART003389029},
author={Aşkan Vala Can and Kol Seda and Aydemir Nihan and Oral Ahmet Yavuz},
title={Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications},
journal={Carbon Letters},
issn={1976-4251},
year={2026},
volume={36},
number={3},
pages={1417-1434},
doi={10.1007/s42823-026-01071-0}
TY - JOUR
AU - Aşkan Vala Can
AU - Kol Seda
AU - Aydemir Nihan
AU - Oral Ahmet Yavuz
TI - Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications
JO - Carbon Letters
PY - 2026
VL - 36
IS - 3
PB - Korean Carbon Society
SP - 1417
EP - 1434
SN - 1976-4251
AB - Thermoelectric materials enable direct heat-to-electricity conversion. They have gained increasing interest in sustainable and wearable energy-harvesting systems. However, progress in flexible thermoelectric devices remains limited by the shortage of high-performance n-type organic materials, hindering the development of efficient p–n complementary modules. Laser-induced graphene (LIG) has attracted considerable attention for thermoelectric applications due to its high electrical conductivity, scalable fabrication, and compatibility with flexible substrates. However, LIG produced from polyimide typically exhibits p-type behavior, which limits its applicability in thermoelectric modules requiring complementary n-type materials. In this study, we address this limitation by introducing a simple and scalable urea-assisted strategy to convert p-type LIG into n-type LIG through nitrogen doping during the laser-induced graphitization process. First, we have fabricated LIG by direct laser writing on polyimide and subsequently treated with 5 and 10 wt% urea solutions, followed by mild annealing. Subsequent structural and chemical characterizations confirmed effective nitrogen incorporation, dominated by graphitic-N species, while preserving the porous 3D LIG network. Thermoelectric measurements revealed enhanced electrical conductivity (up to 1120 S/m) and a clear p-to-n transition, as evidenced by negative Seebeck coefficients in urea-treated films. The optimized LIG-10 N sample delivered the highest thermoelectric performance, reaching a power factor of 0.136 µW m⁻¹ K⁻² at 60 °C. Overall, this work provides a practical route for engineering n-type LIG, supporting the development of flexible thermoelectric modules for wearable and low-power energy-harvesting applications.
KW - Laser-induced Graphene Nitrogen doping Urea treatment n-type conversion Thermoelectric properties
DO - 10.1007/s42823-026-01071-0
ER -
Aşkan Vala Can, Kol Seda, Aydemir Nihan and Oral Ahmet Yavuz. (2026). Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications. Carbon Letters, 36(3), 1417-1434.
Aşkan Vala Can, Kol Seda, Aydemir Nihan and Oral Ahmet Yavuz. 2026, "Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications", Carbon Letters, vol.36, no.3 pp.1417-1434. Available from: doi:10.1007/s42823-026-01071-0
Aşkan Vala Can, Kol Seda, Aydemir Nihan, Oral Ahmet Yavuz "Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications" Carbon Letters 36.3 pp.1417-1434 (2026) : 1417.
Aşkan Vala Can, Kol Seda, Aydemir Nihan, Oral Ahmet Yavuz. Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications. 2026; 36(3), 1417-1434. Available from: doi:10.1007/s42823-026-01071-0
Aşkan Vala Can, Kol Seda, Aydemir Nihan and Oral Ahmet Yavuz. "Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications" Carbon Letters 36, no.3 (2026) : 1417-1434.doi: 10.1007/s42823-026-01071-0
Aşkan Vala Can; Kol Seda; Aydemir Nihan; Oral Ahmet Yavuz. Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications. Carbon Letters, 36(3), 1417-1434. doi: 10.1007/s42823-026-01071-0
Aşkan Vala Can; Kol Seda; Aydemir Nihan; Oral Ahmet Yavuz. Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications. Carbon Letters. 2026; 36(3) 1417-1434. doi: 10.1007/s42823-026-01071-0
Aşkan Vala Can, Kol Seda, Aydemir Nihan, Oral Ahmet Yavuz. Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications. 2026; 36(3), 1417-1434. Available from: doi:10.1007/s42823-026-01071-0
Aşkan Vala Can, Kol Seda, Aydemir Nihan and Oral Ahmet Yavuz. "Urea-assisted N-type conversion of laser-induced graphene for thermoelectric applications" Carbon Letters 36, no.3 (2026) : 1417-1434.doi: 10.1007/s42823-026-01071-0
