Magnetic Field-Enhancing Photocatalytic Reaction in Micro Optofluidic Chip Reactor

A small external magnetic field (100-1000 Oe) was demonstrated to enhance the photocatalytic degradation of methyl orange (MO) using TiO₂ NPs in micro optofluidic chip (MOFC) reactors. The rectangular shape of the fluidic channel and TiO₂ deposited only onto the lower glass substrate leads to a selectively enhancing photocatalytic reactions by magnetic field in specific directions. Utilizing ethyl alcohol as a scavenger presented the difference between generated hot-hole (hVB⁺) and hot-electron (eCB^-) pathways of photocatalytic reactions. Effects of dissolved oxygen (DO) and hydroxyl ions (OH^-) are all demonstrated in a magnetic field-enhancing photocatalytic reaction. The experimental results demonstrate great potential for practical applications utilizing low-price fixed magnets in the field of green chemistry.