In this study, ultrasonic spray pyrolysis combined with salt-assisted decomposition, a process that adds sodium nitrate (NaNO3) into a titanium precursor solution, is used to synthesize nanosized titanium dioxide (TiO2) particles. The added NaNO3 prevents the agglomeration of the primary nanoparticles in the pyrolysis process. The nanoparticles are obtained after a washing process, removing NaNO3 and NaF from the secondary particles, which consist of the salts and TiO2 nanoparticles. The effects of pyrolysis temperature on the size, crystallographic characteristics, and bandgap energy of the synthesized nanoparticles are systematically investigated. The synthesized TiO2 nanoparticles have a size of approximately 2–10 nm a bandgap energy of 3.1–3.25 eV, depending on the synthetic temperature. These differences in properties affect the photocatalytic activities of the synthesized TiO2 nanoparticles.

Abstract
 1. 서 론
 2. 실험 방법
 3. 결과 및 고찰
 4. 결 론
 References

• 유재현(서울과학기술대학교 신소재공학과) | Jae-Hyun Yoo (Department of Materials Science and Engineering, Seoul National University of Science and Technology)
• 지명준(서울과학기술대학교 신소재공학과) | Myeong-Jun Ji (Department of Materials Science and Engineering, Seoul National University of Science and Technology)
• 박우영(서울과학기술대학교 신소재공학과) | Woo-Young Park (Department of Materials Science and Engineering, Seoul National University of Science and Technology)
• 이영인(서울과학기술대학교 신소재공학과) | Young-In Lee (Department of Materials Science and Engineering, Seoul National University of Science and Technology) Corresponding Author