Magnetic Fields in TiO₂ Synthesis: Targeting Multicarbon Products from the CO₂ Reduction Reaction

Increasing CO₂ emissions into the atmosphere have led to global warming and other climate issues. One way to combat this is through the photocatalytic CO₂ reduction reaction. In this reaction, CO₂ and water are used as reactants to produce value-added products such as CO, CH₄, CH₃OH, and C₂H₅OH. TiO₂ is one of the most common photocatalysts due to its relatively high efficiency, low cost, and availability. However, traditionally synthesized TiO₂ materials suffer from the low activity in converting CO₂ into these products. One strategy to improve CO₂ conversion activity is through crystal facet engineering. For the first time, magnetic fields were introduced during the synthesis of TiO₂ nanotubes, leading to a new type of TiO₂ {100} facet containing more active low-coordinate Ti atoms. These facets were found to promote the coupling of adsorbed *CO intermediates, enabling the conversion of CO₂ into C₂H₅OH with a yield rate of 6.16 µmol g^-1 h^-1 – 22 times higher than that of pristine TiO₂.