Calcined Co(II)-Triethylenetetramine, Co(II)- Polyaniline-Thiourea as the Cathode Catalyst of Proton Exchanged Membrane Fuel Cell

Wen-Yao Huang; Li-Cheng Jheng; Tar-Hwa Hsieh; Ko-Shan Ho; Yen-Zen Wang; Yi-Jhun Gao; Po-Hao Tseng

doi:10.3390/polym12123070

Calcined Co(II)-Triethylenetetramine, Co(II)- Polyaniline-Thiourea as the Cathode Catalyst of Proton Exchanged Membrane Fuel Cell

Polymers (Basel). 2020 Dec 21;12(12):3070. doi: 10.3390/polym12123070.

Authors

Wen-Yao Huang¹, Li-Cheng Jheng², Tar-Hwa Hsieh², Ko-Shan Ho², Yen-Zen Wang³, Yi-Jhun Gao², Po-Hao Tseng²

Affiliations

¹ Department of Photonics, National Sun Yat-sen University, 70 Lienhai Rd., Kaohsiung 80424, Taiwan.
² Department of Chemical and Materials Engineering, National Kaohsiung University of Science and Technology, 415, Chien-Kuo Road, Kaohsiung 80782, Taiwan.
³ Department of Chemical and Materials Engineering, National Yun-Lin University of Science and Technology, Yun-Lin 64002, Taiwan.

Abstract

Triethylenetetramine (TETA) and thiourea complexed Cobalt(II) (Co(II)) ions are used as cathode catalysts for proton exchanged membrane fuel cells (PEMFCs) under the protection of polyaniline (PANI) which can become a conducting medium after calcination. Fourier-transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) spectra clearly reveal the presence of typical carbon nitride and sulfide bonds of the calcined Nitrogen (N)- or Sulfur (S)-doped co-catalysts. Clear (002) and (100) planes of carbon-related X-ray diffraction patterns are found for co-catalysts after calcination, related to the formation of a conducting medium after the calcination of PANI. An increasing intensity ratio of the D to G band of the Raman spectra reveal the doping of N and S elements. More porous surfaces of co-catalysts are found in scanning electronic microscopy (SEM) micropictures when prepared in the presence of both TETA and thiourea (CoNxSyC). Linear sweep voltammetry (LSV) curves show the highest reducing current to be 4 mAcm^-2 at 1600 rpm for CoNxSyC, indicating the necessity for both N- and S-doping. The membrane electrode assemblies (MEA) prepared with the cathode made of CoNxSyC produces the highest maximum power density, close to 180 mW cm^-2.

Keywords: co-catalyst; oxygen reduction reaction; polyaniline; thiourea; triethylenetetramine.