Investigation of nanofluids in alkaline electrolytes: Stability, electrical properties, and hydrogen production

Utilizing solar energy efficiently and manufacturing hydrogen economically are the primary goals in the energy industry. In this paper, we present a novel method to solve both issues by exploiting the electrolysis of electrolyte-based nanofluids under the illumination of solar light. The carbon black nanoparticles/sodium hydroxide solution mixture of electrolyte nanofluids were prepared, which were then electrolyzed in a Hoffman voltameter to produce hydrogen. The results showed the hydrogen production rate improved by 23.62% when carbon black was used in the electrolyte. The optimal carbon black concentration was 0.04% or 0.2% depending on the experimental set-up used. Finally, a theoretical model was built to evaluate the total hydrogen production, which showed a good agreement with the experimental results when the carbon black concentration was lower than 0.1 wt%.