Direct PEM fuel cell using “organic chemical hydrides” with zero-CO2 emission and low-crossover

Abstract

A series of “organic chemical hydrides” such as cyclohexane, methylcyclohexane, cyclohexene, 2-propanol, and cyclohexanol were applied to the direct PEM fuel cell. High performances of the PEM fuel cell were achieved by using cyclohexane (OCV = 920 mV, PD_max = 15 mW cm⁻²) and 2-propanol (OCV = 790 mV, PD_max = 78 mW cm⁻²) as fuels without CO₂ emissions. The rates of fuel crossover for cyclohexane, 2-propanol, and methanol were estimated, and the rates of fuel permeation of cyclohexane and 2-propanol were lower than that of methanol. Water electrolysis and electro-reductive hydrogenation of acetone mediated by PEM were carried out and formation of 2-propanol in cathode side was observed. This system is the first example of a “rechargeable” direct fuel cell.