학술논문
Gold Nanospheres-Encapsulated Yolk-Shell Structure: Application To Environmental Catalyst / 금 나노 구체가 담지 된 요크-쉘 실리카 구조물: 환경 촉매 응용
Document Type
Dissertation/ Thesis
Author
Source
Subject
Language
English
Abstract
본 논문은 과황산을 활성화하고 수상 유기 화합물을 분해하는 환경친화적이며 오염물질의 선택적 분해가 가능하고 반응성이 우수한 새로운 형태의 촉매 (금 나노 구체가 담지된 메조 다공성의 실리카 나노 캡슐, AuNS@ySiO2)를 소개합니다. AuNS@ySiO2는 개선된 Stöber 방법과 종자 생장 방법을 사용하여 합성되었으며, 합성된 AuNS@ySiO2는 수상 유기 오염물질 분해에 탁월한 성능을 보였습니다. AuNS@ySiO2에 대한 구조적인 특징은 전계방사형 투과전자 현미경, 전계방출형 주사전자 현미경, 에너지 분산형 X-선 분석, X-ray 회절 분석법, 입도분석기를 사용하여 확인했습니다. 금 나노 구체를 캡슐화함으로써 금 나노 구체의 대규모 응집을 방지하고, 과황산을 활성화하여 유기 오염물질을 효과적으로 분해할 수 있습니다. 페놀 분해 측정은 고속 분리 액체 크로마토그래피를 사용하였으며, 페놀 용액 (0.5 mM)은 과황산 (10 mM)과 AuNS@ySiO2의 활성화에 의해 pH 3에서 20분 만에 100% 분해되었습니다. 또한 AuNS@ySiO2/과황산 시스템은 페놀에 대한 선택적 반응성을 나타냈으며, 메조 다공성의 실리카 껍질의 체 거름 효과로 인해 고농도의 천연 유기물 존재 하에도 반응속도가 거의 억제되지 않았습니다. 프로브 테스트, 라디칼 소거 실험 및 전자 상자기성 공명 분광법을 통해 페놀 분해가 라디칼 생성에 의해서가 아닌 논라디칼 메커니즘이 지배적으로 작용하여 수행됨을 확인했습니다. 이러한 결과를 바탕으로, 고농도의 천연 유기물 및 간섭 물질의 존재에도 사용 가능한 촉매에 대한 새로운 방향성을 제시합니다.
This study introduces gold nanospheres encapsulated mesoporous silica nanocapsules (AuNS@ySiO2) as an environmentally friendly, target-selective, and highly reactive catalyst to activate persulfate and remove organic compounds in aqueous phase. The AuNS@ySiO2 was synthesized by slightly modified Stöber and seeded growth method, and the obtained AuNS@ySiO2 exhibited outstanding performance at organic compounds degradation in aqueous phase, and its structural characteristics were analyzed by FE-TEM, FE-SEM, EDS, XRD, and PSA. By encapsulating the gold nanospheres (AuNS), massive aggregation of AuNS is prevented and persulfate can be activated, whereby effective degradation of organic compounds was achieved. Rapid separation liquid chromatography (RSLC) was used to measure phenol degradation, the phenol solution (0.5 mM) was perfectly degraded by persulfate (10 mM) activation within 20 min at pH 3 using AuNS@ySiO2 (2.0 g/L) as a catalyst. Through probe test, radical scavenging experiments and electron paramagnetic resonance spectroscopy (EPR), it was confirmed that the phenol degradation was carried out by non-radical mechanism. The AuNS@ySiO2/persulfate showed target-selective reactivity to phenol and degradation kinetics were almost not restrained by the natural organic matter (NOM) and polyvinylpyrrolidone (PVP) due to the sieve effect of mesoporous silica shell. Based on these results, this work provides a new way of organic contaminants degradation under high concentration of natural organic matter and interfering substances.
This study introduces gold nanospheres encapsulated mesoporous silica nanocapsules (AuNS@ySiO2) as an environmentally friendly, target-selective, and highly reactive catalyst to activate persulfate and remove organic compounds in aqueous phase. The AuNS@ySiO2 was synthesized by slightly modified Stöber and seeded growth method, and the obtained AuNS@ySiO2 exhibited outstanding performance at organic compounds degradation in aqueous phase, and its structural characteristics were analyzed by FE-TEM, FE-SEM, EDS, XRD, and PSA. By encapsulating the gold nanospheres (AuNS), massive aggregation of AuNS is prevented and persulfate can be activated, whereby effective degradation of organic compounds was achieved. Rapid separation liquid chromatography (RSLC) was used to measure phenol degradation, the phenol solution (0.5 mM) was perfectly degraded by persulfate (10 mM) activation within 20 min at pH 3 using AuNS@ySiO2 (2.0 g/L) as a catalyst. Through probe test, radical scavenging experiments and electron paramagnetic resonance spectroscopy (EPR), it was confirmed that the phenol degradation was carried out by non-radical mechanism. The AuNS@ySiO2/persulfate showed target-selective reactivity to phenol and degradation kinetics were almost not restrained by the natural organic matter (NOM) and polyvinylpyrrolidone (PVP) due to the sieve effect of mesoporous silica shell. Based on these results, this work provides a new way of organic contaminants degradation under high concentration of natural organic matter and interfering substances.