Ga₂O₃ Heterophase Junctions For Efficient Photoreduction Of CO₂

Nowadays,global warming associated with the increasing concentration of CO2 is one of the most important environmental issues.Photoreduction of CO2 into fossil fuels with photocatalysts,such as Fe2O3,TiO2,Cu2O,has been a promising method to solve the growing energy and environmental problems.However,the low activity of CO2 reduction reaction is still the main restraint for the widely commercial application.Many efforts have been made to improve the efficiency of the CO2 photoreduction,such as building the built-in electric field to improve the charge separation in photovoltaics on semiconductors,designing a porous structure material to increase the specific surface area,using the nanophase materials for short migration distance of electron and hole.Preparation of heterogeneous junction,as well as phase junction has been an effective way for better charge separation on semiconductors.In this arcticle,we prepared a mesoporous single-crystal Ga2O3 nanoplate with a new two-step hydrothermal method.On this basis,we further prepared ?-? Ga2O3 nanoplates which shows a good photocatalytic activity for CO2 photoreduction.We found that the designed mesoporous structure greatly improves the efficiency of the CO2 reduction,and the fabrication of Ga2O3 ?-? phase junctions promotes the charge separation for CO2 reduction reaction.To get the better activity,an accuracy ratio of a and ? phase was also discovered.In this work,we investigated the band structure and density of states(DOS)of ?-? phase junctions using hybrid density functional(DFT)calculation.