Size-dependent electrocatalytic activities of printed Co3O4 films for a monolithic photovoltaic-electrolytic hydrogen generation system

作者：Jeon Hyo Sang; Nugroho Agung; Kim Jaehoon^*; Kim Honggon; Min Byoung Koun

来源：International Journal of Hydrogen Energy, 2011, 36(17): 10587-10592.

DOI：10.1016/j.ijhydene.2011.06.006

• Water splitting
• Hydrogen
• Co3O4
• Electrocatalysts
• Electrochemical
• Particle size

As an electrocatalyst in a monolithic PV-electrolytic cell for water splitting hydrogen generation Co3O4 films were prepared by a paste coating method using Co3O4 particles. Different sized Co3O4 particles with average diameters of 145.9, 63.3 and 36.5 nm were prepared using a supercritical hydrothermal synthesis method. Electrochemical properties with respect to the particle size in the film were investigated by evaluating overpotential, charge transfer resistance (R-ct), and number of active sites (q*). The relation between overpotential in water oxidation at 5 mA/cm(2) and BET surface area showed a slope of -73.8 +/- 6.6, implying strong particle size dependence on electrocatalytic activity. Moreover, the R-ct and q* values and the actual hydrogen evolution rate indicated that the electrocatalytic activity of Co3O4 is attributed to physical properties (e.g. particle size) of the film. Whereas, intrinsic single site activity of the film was not significantly changed with respect to the particle size in the film.

• 出版日期2011-8