2020 年 18 巻 p. 110-115
We have prepared La2O3 supported Ga2O3 (Ga2O3/La2O3) photocatalyst to improve the photocatalytic activity of Ga2O3 for CO2 reduction with water under ultraviolet light irradiation without a noble metal cocatalyst. Significant improvement on both CO2 reduction and water splitting was attained compared with those for non-supported Ga2O3 and La2O3. The improvement is attributed to the transformation of the La2O3 surface to NaLa(CO3)2 during the photocatalytic reduction tests in aqueous solution of NaHCO3. NaLa(CO3)2 was preferentially formed on the surface of La2O3 without changing Ga2O3 resulting in the structure of Ga2O3 supported by NaLa(CO3)2. Once NaLa(CO3)2 fully covered the surface of La2O3, the high catalytic activity was kept long.
