Electrochemical investigation of bismuth-doped anode materials for low‑temperature solid oxide fuel cells with boosted voltage using a DC-DC voltage converter

Abstract Conventional solid oxide fuel cells (SOFCs) work at high operating temperatures (800–1,000°C). Lowering the operating temperature of SOFCs reduces the open-circuit voltage (OCV) and performance. Herein, a scheme was established to boost the voltage of the developed SOFC using a DC-DC voltage booster. The LTspice technique was used to develop a DC-DC booster, and the code was generated with a minimum of 0.7 V. For experimental evidence, Bi x Ag 1.00 Fe 1− x Zn 2 O 7+ δ (BAFZ oxide) materials were synthesized to investigate anodic properties. UV-vis and Fourier transform infrared spectroscopy techniques were used to determine the band gaps and functional groups. The vibrational modes of composite materials were studied via Raman spectroscopy. A slight peak shift toward a higher wavenumber was noted in the BAFZ oxide sample attributed to the addition of bismuth trioxide (Bi 2 O 3 ). The conductivity was measured and found to be 1.2 S/cm at 600°C in a H 2 atmosphere. Fuel cell performance was also measured in the temperature range of 400–620°C, and a maximum OCV of 1.1 V was achieved at 620°C. Finally, the boosted voltage was recorded at 2.2 V under the same circumstances using a DC-DC booster.