초음파-가시광선 조건 하 Ag6Si2O7/SmFeO3 복합 촉매를 이용한 H2O2의 생성 및 시프로플록사신 광분해 제거 연구 = Fabrication of highly effective Ag6Si2O7/SmFeO3 heterojunction with synergistically enhanced sonophotocatalytic degradation of ciprofloxacin and production of H2O2: Influencing factors and degradation mechanism

다국어 초록 (Multilingual Abstract)

The design of effective bifunctional catalysts for the destruction of refractory pollutants and the production of H2O2 remains a major challenge. In this study, a number of new Ag6Si2O7/SmFeO3 (ASF) heterojunction catalysts were reasonably fabricated through a simple precipitation strategy. The properties of the prepared ASF nanocomposites were confirmed through various characterization analysis. In particular, ASF-1.5 samples show excellent sonophotocatalytic efficiency (94.9%) on 60 min irradiation at an initial ciprofloxacin (CIP) concentration of 10 mg/L, catalytic capacity of 0.6 g/L, US power 400W, pH 5.0, and US frequency of 40 kHz. In addition, the optimized ASF-1.5 sample showed the best H2O2 production rate of 258.5 μM, which was 2.92 times higher than bare Ag6Si2O7. Scavenging experiments demonstrated that ∙OH and h+ are the first reactive oxidized species (ROS) in CIP degradation reactions. The synergistic effects of ultrasound and visible light can then promote the production of reactive oxide species, resulting in good efficiency in CIP degradation and H2O2 generation through ASF-1.5 heterojunction. Furthermore, a potential pathway for CIP degradation and provisional exposure catalytic mechanisms have been established. In summary, this study provided new insights into the rational design of highly effective ASF sonophotocatalysts for innovative energy production and ecological applications.

목차 (Table of Contents)

• 1. 서론 1
• 2. 문헌 연구 5
• 2. 1. 수중 시프로플록사신(CIP)의 특성 5
• 2. 2. 수중 CIP의 영향 7
• 2. 3. 가시광선을 이용한 오염물질 제거기술 9
• 2. 4. 초음파 처리 10
• 2. 5. 페로브스카이트 구조 물질 11
• 2. 6. 헤테로 접합을 통한 밴드구조 설계 14
• 2. 7. H2O2 생성 실험 16
• 2. 8. 오염물질 농도 분석 17
• 3. 실험재료 및 방법 18
• 3. 1. 실험재료 18
• 3. 2. Ag6Si2O7 합성 19
• 3. 3. SmFeO3 합성 20
• 3. 4. Ag6Si2O7/SmFeO3 합성 21
• 3. 5. 특성 분석 23
• 4. 연구결과 24
• 4. 1. 합성한 촉매제의 특성 분석 결과 24
• 4. 1. 1. PXRD 24
• 4. 1. 2. XPS 26
• 4. 1. 3. Zeta potential 29
• 4. 1. 4. FTIR 31
• 4. 1. 5. SEM and TEM 33
• 4. 1. 6. BET 35
• 4. 2. 광∙전기화학적 특성 분석 38
• 4. 2. 1. UV-DRS 38
• 4. 2. 2. VB-XPS 40
• 4. 2. 3. Photoluminescence 42
• 4. 2. 4. EIS and Photocurrent 44
• 4. 2. 5. ESR 46
• 4. 3. 초음파-광분해 실험 48
• 4. 3. 1. CIP의 초음파-광촉매 분해 49
• 4. 3. 2. 실험조건의 영향 분석 53
• 4. 3. 3. 초음파-광 조건 하의 H2O2 생성 연구 59
• 4. 3. 4. 라디칼 제한 실험 63
• 4. 3. 5. ASF 촉매제의 재사용성 실험 65
• 4. 3. 6. ASF 촉매제의 CIP 분해 메커니즘 규명 67
• 4. 3. 7. CIP의 초음파-광 분해경로 70
• 5. 결론 76
• References 77
• (Abstract) 87