Water-insoluble PbSO4 only slightly dissolved in an amide-type hydrophobic protic ionic liquid (IL); the protonated betaine bis((trifluoromethyl)sulfonyl)amide ([Hbet][TESA]). However, the paste of [Hbet][TFSA]-PbSO4 coated on screen-printed carbon electrode (SPCE) could be electrochemically converted to Pb or PbO2 in aqueous 0.1 M KCl via constant-potential electrolysis for the former and continuous cyclic voltammetry in 0.1 M NaOH for the latter. The formation of PbO2, which could be converted to CoOx (containing Co3O4) through galvanic displacement in a Co(NO3)(2) aqueous solution, was verified with Raman scattering spectroscopy and X-ray photoelectron spectroscopy (XPS); the latter also verified the formation of Co3O4. The CoOx-modified electrode showed activity and high stability towards the oxygen evolution reaction (OER) in alkaline solutions. The approach shown in this study can be further developed as a procedure for extracting Pb metal or preparing CoOx catalysts from wastes, such as the discarded lead-storage batteries.