Preparation of magnetic cobalt-based catalyst for hydrogen generation from alkaline NaBH4 solution

摘要

A fast and simple fabrication process was utilized for preparation of cobalt-based catalysts. Compared with other noble-metal catalysts, it is cost-effective, because of the low price of cobalt and capability of rapid-production and easiness in scale-up manufacturing of such catalysts. The magnetic property of the cobalt-based catalysts makes it convenient for recycling spent catalysts. Furthermore, magnetic catalysts can be removed easily to stop the hydrogen production, when hydrogen is no more required in applications. Certainly, this promotes the safe and reliable production of hydrogen and makes it as a safe portable energy source. The rates of hydrogen generation from hydrolysis of alkaline NaBH4 solution were determined as a function of temperature, NaBH4 concentration, and NaOH concentration in presence of prepared catalysts. Production rate of ultrapure hydrogen, as high as 329 ml·min~(-1)·g~(-1), was reached at 55oC. This high purity of hydrogen could be directly used as the fuel to PEMFC without additional requirement in hydrogen purification.^