LAUSR

A novel micro-solid oxide fuel cell ($$\upmu $$μ-SOFC), with a rectangular saw-tooth shape, was designed with a 50 wt% $$\hbox {BYCF}+50 \hbox { wt}$$BYCF+50wt% $$\hbox {GDC}_{10}$$GDC10 cathode and a 60 wt% $$\hbox {NiO}+40 \hbox { wt}$$NiO+40wt% $$\hbox {GDC}_{10}$$GDC10 anode deposited on a $$\hbox {GDC}_{10}$$GDC10 electrolyte substrate by the spray pyrolysis technique. $$\upmu $$μ-SOFC receives methane only ($$\hbox {CH}_{4}$$CH4) as fuel gas from one side. The fuel gas was applied at a flow rate of 0.2 l $$\hbox {min}^{-1}$$min-1. The power density obtained was $$1.0~\upmu \hbox {W}$$1.0μW at $$800{^\circ }\hbox {C}$$800∘C. Voltage levels generated by the $$\upmu $$μ-SOFC at 40–99.99% $$\hbox {CH}_{4}$$CH4 was highly accurate representing the quantity of $$\hbox {CH}_{4}$$CH4. Low accuracy was observed at 10–30% of $$\hbox {CH}_{4}$$CH4. Therefore, $$\upmu $$μ-SOFC is an application of SOFC technology to be a sensor for economically detecting CH$$_4$$4 in a biogas system, while being capable of operating in humid conditions at high temperatures.