용액연소법으로 제조한 ZnO 나노분말 합성과 수질 속 질산성 질소와 중금속 제거

국문 초록 (Abstract)

출발물질과 연료의 종류에 따라 광촉매용 ZnO 나노분말을 제조하였다. 이렇게 제조된 분말은 XRD로부터 결정상을 확인할 수 있었고 TGA로부터 하소온도를 결정할 수 있었다. 분말의 비표면적은 BET법으로 측정되었고 평균입자 크기와 형태는 SEM과 TEM으로부터 조사하였다. 물리적 특성을 조사한 결과 출발물질은 Zinc hydroxide를 사용하고 연료로는 Glycine를 사용한 경우에 크기와 비표면적이 30nm와 120m2/g로 가장 뛰어난 특성을 보였다. Glycine/Zinc hydroxide의 ratio에 따른 전기적 특성을 Hall measurement로 측정하고 광학적 특성을 Photoluminescence(PL) spectra로 측정하였다. fuel/oxidant ratio 0.8일 때 carrier 농도가 가장 높았고 자외선 흡수 능력이 가장 뛰어났다. 가장 좋은 분말 특성을 보여준 Glycine/Zinc hydroxide의 ratio가 0.8인 분말을 사용하여 ICP 표준용액과 실 폐액을 이용하여 질산성 질소와 중금속 제거율을 알아보았다. 그 결과 상용 ZnO와 TiO2(P-25, PHHLT)등 다른 광촉매 분말에 비해 월등한 효율을 보여주었다.

다국어 초록 (Multilingual Abstract)

Abstract

ZnO nanopowder was synthesized by Solution-Combustion Method (SCM) using various starting materials and fuels respectively. X-ray diffraction (XRD) was used to confirm the crystalline phase of synthesized ZnO powders. Thermogravimetric Analysis (TGA) was used to investigate the calcination degree of ZnO powders. Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) were also used to investigate the average particle size and shape. Specific surface area of the powder was measured by Brunauer-Emett-Teller (BET) method. From these measurements, the ZnO powder synthesized with Glycine/Zinc hydroxide ratio=0.8 showed the best powder characteristics, average particle size of 30nm and the specific surface area of 120m2/g. Hall measurement was used to investigate the electric properties of ZnO powders. Photoluminescence (PL) was used to investigate the optical properties of ZnO powders. The ZnO powder synthesized with fuel/oxidant ratio=0.8 showed the highest carrier concentration and the excellent ultraviolet absorption ability. The photoreduction activity of the SCM ZnO was then compared with the other semiconductor photocatalyst powders such as TiO2 powder, and TiO2 powder by homogeneous precipitation process at low temperature (HPPLT) and commercial ZnO.

목차 (Table of Contents)

• 그림목차 ······························································· ⅰ
• 표목차 ·································································· ⅲ
• 국문초록 ······························································· ⅳ
• 제 1 장 서 론 ························································· 1
• 제 2 장 이론적 고찰 ················································· 3
• 2-1 ZnO의 특성 ····················································· 3
• 2-2 용액연소법 ······················································ 5
• 제 3 장 실험 방법 및 측정 ········································· 8
• 3-1 출발 물질과 조성 ·············································· 8
• 3-2 상 분석과 미세구조 관찰 ···································· 10
• 3-3 전기적 특성 평가 ············································· 10
• 3-4 광학적 특성 평가 ············································· 10
• 3-5 광촉매 특성 평가 ············································· 11
• 3-5-1 광촉매 반응기 제작 ····································· 11
• 3-5-2 표준용액을 이용한 광촉매 특성 평가 ················ 12
• 3-5-3 실폐액을 이용한 광촉매 특성 평가 ··················· 12
• 제 4 장 결과 및 고찰 ··············································· 14
• 4-1 상분석 및 미세구조 고찰 ···································· 14
• 4-2 BET 분석 ······················································ 27
• 4-3 Hall measurement 측정 ····································· 29
• 4-4 Photoluminescence(PL) spectra 측정 ······················ 29
• 4-5 Inductively Coupled Plasma - Atomic Emission Spectrometer(ICP-AES) 측정· 33
• 4-5-1 Cu 제거율 ················································ 33
• 4-5-2 Pb 제거율 ················································ 33
• 4-5-3 Fe 제거율 ················································ 34
• 4-5-4 질산성 질소 제거율 ····································· 34
• 4-6 Atomic Absorption Spectrometer(AAS) 측정 ············ 41
• 4-6-1 Ag 제거율 ················································ 41
• 4-6-2 Pb 제거율 ················································ 41
• 4-6-3 Cu 제거율 ················································ 42
• 4-6-4 TOC 제거율 ············································· 42
• 제 5 장 결 론 ························································ 48
• 참고문헌 ······························································· 51
• Abstract ······························································ 52