A direct liquid fuel cell powered by 1,3- or 1,2-propanediol

In this work we compare the behavior of the 1,2 and 1,3 isomers of propanediol (PD) when electrochemically oxidized in alkaline media both in a 3 electrode electrochemical cell and in an operating split pH, alkaline-acid fuel cell with a cation exchange membrane. In the electrochemical cell, we use voltammetry and amperometry to determine that the 1,3-PD oxidizes nearly 3 times more efficiently than the 1,2-PD. In the operating fuel cell, we find that the maximum power density of the 1,3-PD is 185 mW cm−2 at 60 °C with a Pt black cathode and 103 mW cm−2 with a carbon black cathode. In contrast, the 1,2-PD isomer reaches only 102 mW cm−2 with Pt cathode and 64 mW cm−2 with carbon cathode. Previous work has primarily considered the 1,2-PD isomer, but recent improvements to the synthesis of 1,3-PD make it a promising fuel for better performance than the 1,2-PD isomer. In addition, the use of the split pH fuel cell makes both isomers viable for higher power demands than previously shown and with the option of using carbon black as the cathode material.