Scandium-III-nitrides:\nA New Material Platform for\nSemiconductor Photocatalysts with High Reducing Power

Semiconductor\nnanowires have become emerging photocatalysts in\nartificial photosynthesis processes for solar fuel production. For\nreduction reactions, semiconductor photocatalysts with high reducing\npowers are highly desirable, especially for chemicals that are extremely\ndifficult to reduce. This study introduces a new semiconductor photocatalyst,\nscandium (Sc)-III-nitrides, which have higher reducing powers than\nall conventional semiconductor photocatalysts. In specific, we focus\non Sc<sub><i>x</i></sub>Ga<sub>1–<i>x</i></sub>N (ScGaN) nanowires. The detailed material synthesis and characterization\nof such nanowires are explored, and the photocatalytic reduction of\ncarbon dioxide (CO<sub>2</sub>), as an example of chemicals that are\ndifficult to reduce, is also performed. The photocatalytic CO<sub>2</sub> reduction using GaN, a well-known high-performance semiconductor\nphotocatalyst, is conducted as well as a reference. It is found that\ncompared to using GaN nanowires, using ScGaN nanowires can significantly\nincrease the production rate of formic acid (HCOOH). Moreover, ScGaN\nnanowires can further reduce HCOOH to methanol (CH<sub>3</sub>OH).