Ti4+ Ions-Doped Metal–Organic Framework (MOF-74) for Photoreduction of Carbon Dioxide

The development of efficient and sustainable methods for reducing carbon dioxide (CO₂) and converting it into valuable hydrocarbons has gained significant attention. In this study, researchers focused on Ti⁴⁺-doped metal-organic framework (MOF-74) photocatalysts. The incorporation of Ti⁴⁺ ions into the MOF-74 structure was achieved through a one-pot hydrothermal method. By replacing Zn²⁺ ions with Ti⁴⁺ ions in a substitutional manner, researchers have aimed to enhance the photocatalytic activity of the CO₂ reduction. The obtained Ti⁴⁺-doped MOF-74 photocatalysts exhibited a significantly improved performance in the reduction of CO₂ into carbon monoxide (CO). The doping of Ti⁴⁺ ions induced energy bands below the conduction band minimum (CBM) of MOF-74, extending the visible response range and enabling the photocatalysts to utilize a broader spectrum of light for catalytic reactions. This extension of the visible response range enables photocatalysts to utilize a broader spectrum of light for catalytic reactions. The incorporation of Ti⁴⁺ ions not only extends the visible response range but also suppresses charge carrier recombination. This work provides valuable insights into the design principles of MOF-based photocatalysts and paves the way for their practical implementation in addressing the energy crisis and reducing greenhouse gas emissions.