Laser Induced Magnesium Oxide Reduction for Renewable Energy Cycle with Solar Power

Abstract

We succeeded in producing Mg from MgO without reducing agent using high power cw laser. Mg in turn can react with water to produce hydrogen, heat and MgO, thus natural resources like solar power can be stored as chemical energy. In this study, a focused CO₂ laser irradiated MgO target in vacuum, high temperature is exerted in tiny spot thus Mg production in equilibrium is achievable. The resultant Mg vapor is deposited on Cu plate and analyzed by EPMA (electron probe micro analysis); the results showed points of more than 30% mol fraction of Mg deposited, with an average of 8 mol%. So far bulk analysis results showed that 6 mol% of Mg is obtained as solid deposit, which can be translated to energy conversion efficiency of 0.35 mg/kJ. These experiments showed that our scheme can be used for magnesium production with higher efficiency and large throughput.