Hydrogen Generation from the Hydrolysis of Sodium Hypophosphite Using CoB2O4 Catalyst for Fuel Cell Operation

The goal of the work involves a radically new approach – establishment of possibility of the use of sodium hypophosphite (NaH₂PO₂) as hydrogen source or the study of the process of its reforming; synthesis of corresponding catalysts and their testing for generation of hydrogen. It is well known that in the process of chemical nickel plating at 80-95 ⁰C, in the course of an interaction between sodium hypophosphite and water the formed atomic hydrogen reduces nickel on the surface of the plated metal. Nickel plating with the participation of sodium hypophosphite is self-catalytic. Overall catalytic reaction of the interaction between hypophosphite and water may be presented as follows:

H₂PO ₂‾ + H₂O → H₂PO ₃‾ + H₂

We have established that in the absence of nickel-ions in the hypophosphite solution, and with the use of so-called Raney nickel catalyst, an intensive separation of hydrogen is possible at high temperatures (80-95 ⁰C), but at room temperature the process practically stops. Hence, by selection of corresponding catalyst the hydrogen production from hypophosphite solution and its use in fuel cell are possible. In the work the hydrogen evolution from aqueous solution of sodium hypophosphite was studied at 10-30 ⁰C by CoB₂O₄ catalyst. In case of 2M NaH₂PO₂ solution hydrogen evolution rate was 3.4-3.6 ml sec^-1 g^-1, which was enough for 0.6 W H₂–O₂ fuel cell operation.

The designate project has been fulfilled by the support of Georgia National Science Foundation. Any idea in this publication is possessed by the authors and may not represent the opinion of “Georgia National Science Foundation"