Ultrasound-assisted Microwave Synthesis of White Fungus-like In<sub>2</sub>S<sub>3</sub> and In<sub>2</sub>S<sub>3</sub>/Cu<sub>1.8</sub>Se Composite for CuIn(S, Se)<sub>2</sub> Film

White fungus-like In2S3 microspheres and In2S3/Cu1.8Se composites were successfully synthesized via a facile ultrasound-assisted microwave method. The reaction temperature could be as low as 70 °C and the reaction time was very short. The In2S3 microspheres were constructed by nanoakes and many cavities existed in the microspheres. In2S3/Cu1.8Se composite was synthesized using the asprepared In2S3 microspheres as the template. Introducing Cu1.8Se compound did not changed the basic morphology of the template. Through doctor blade coating-rapid sintering method, CuIn(S, Se)2 film was further fabricated. The as-prepared film was demonstrated to be flat and compact, which could be applied as chalcopyrite solar cell thin film. Keywords: CuIn(S, Se)2, In2S3, nanostructures, solar cell thin film, ultrasound-assisted microwave.