ICAME-2017 Yildiz University PHOTODEGRADATİON OF WATER-ORGANİC CONTAMİNANTS WİTH SAFE SENSİTİZED ZnO NANOPARTİCLES: A GREEN SUSTAİNABLE METHOD FOR WATER PURİFİCATİON Presented by: Amani Zu’bi Coauthors: Ahed Zyoud & Hikmat Hilal Chemistry Department / An-Najah N. University, Palestien1 ICAME-2017 Yildiz University

ICAME-2017 Yildiz University The problem to solve Palestine suffers serious shortages in pure water supplies. Due to the abuse of ground water resources practiced by settlers. They also dispose their sewage randomly into Palestinian areas Most commonly: (Industrial dyes, phenolderivatives herbicides, pesticides, insecticides, drugs … ec) and heavy metals. Contaminants reach ground & surface water Severe pollution occurs. Purification & recycling of water is needed. ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Different types strategies are used to remove contaminants. But expensive or not efficient. Recently: Natural solar energy has been examined for complete mineralization. Core issue is developing light-sensitive semiconducting materials to catalyze photo-degradation ICAME-2017 Yildiz University

The Idea of Semiconductors Band Diagram: Semiconductor with Non Doping T > 0 Conduction band (Partially Filled) EC EF EV Valence band (Partially Empty) ICAME-2017 Yildiz University

ICAME-2017 Yildiz University How Semiconductors catalyze photodegradation: Semiconductor absorbs photon with (hν > Eg), electron is excited to conduction band, & positive hole remains valence band. electron-hole formation. ICAME-2017 Yildiz University

ICAME-2017 Yildiz University UV Irradiation Experiments Using ZnO Schematic Mechanism of Photo-Excitation ZnO (Semiconductor) by UV Light ICAME-2017 Yildiz University

ICAME-2017 Yildiz University The purpose: Using lab prepared ZnO nano-powder and using it in degrading organic contaminants (Methyle Orange) under solar simulator light using the UV fraction (~4%), taking into account: 1- efficiency 2- recyclability 3- cost 4- environmental safety 5- working under natural conditions. ICAME-2017 Yildiz University

ICAME-2017 Yildiz University ZnO Characterization ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Electronic absorption spectrum for lab-prepared ZnO powder (aqueous suspension). ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Photoluminescence Spectra Photoluminescence emission spectrum measured for ZnO powder (in suspension). ICAME-2017 Yildiz University

X-ray Diffraction (XRD) of ZnO ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Scaning Electron Micrograph images for ZnO 17 nm ICAME-2017 Yildiz University

Solar Simulator Photodegradation Experiments Measuring The %degradation Turn over number Quantum yeild underdifferent Experiment conditions ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Methyl Orange ICAME-2017 Yildiz University

Effect of pH on photo-degradation process intensity 19.0 mW/cm Profiles of photo-degradation reaction for aqueous methyl orange (100 mL, 10 ppm) at different pH values, using ZnO catalyst (0.1g) at room temperature with total radiation Effect of pH of the photo-degradation rate under 19.0 mW/cm2 irradiation pH ~ 7 ~ 5 ~ 2.5 ~ 9 ~ 11 T.N. 1.62 X 10-3 1.94 X 10-3 1.17 X 10-3 8.42 X 10-4 6.71 X 10-4 Q.Y. 4.36X 10-4 4.28 X 10-4 2.92 X 10-4 2.12 X 10-4 1.74 X 10-4 % Degradation 100% 73% 60% 48% ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Effect of temperature Profiles of photo-degradation reaction of methyl orange solution (100 mL, 20 ppm) at different temperatures, using ZnO catalyst (0.1 g) and total irradiation intensity of 19.0 mW/cm2 at pH ~7 Temp. 10 oC 20 oC 30 oC 45 oC T.N. 1.86 X 10-3 2.38 X 10-3 2.87 X 10-3 2.80 X 10-3 Q.Y. 3.52 X10-4 4.28 X10-4 5.44 X 10-4 5.29 X 10-4 % Degradation 62% 70% 84% 81% ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Effect of CO2 and other gas flows Effect of gas streams on methyl orange photo-degradation. Reactions were conducted using methyl orange solution (100 mL, 20 ppm) under 19.0 mW/cm2 irradiation using ZnO (0.1 g) with continuous stirring at 20oC with different gas flows: (a) exposed to air only (b) air flow (c) N2 flow open system (d) CO2 and air flows together (e) CO2 flow (f) closed system with nitrogen flow (g) N2 and CO2 flows together.   exposed to air only air flow N2 flow open system CO2 and air flows together CO2 flow T.N. 2.87 X 10-3 1.72 X 10-3 1.44 X 10-3 0.75 X 10-3 1.03 X 10-3 Q.Y. 5.44 X 10-4 3.25 X 10-4 2.72 X 10-4 1.42 X 10-4 1.95 X10-4 % Degradation 84% 52% 50% 25% 19% ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Effect of contaminant concentration Effect of contaminant concentration under 19.0 mW/cm2 irradiation   10 ppm 20 ppm 30 ppm 40 ppm T.N. 1.73 X 10-3 2.38 X 10-3 2.37 X 10-3 2.29 X 10-3 Q.Y. 3.07 X 10-4 4.28 X 10-4 4.48 X 10-4 4.17 X 10-4 % Degradation 100% 70% 66% 45% ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Effect of catalyst nominal amount on photo-degradation process Effect of catalyst amount on the photo-degradation rate under 19.0 mW/cm2 irradiation   0.05 g 0.10 g 0.20 g 0.3 g T.N. 3.10 X 10-3 1.68 X 10-3 9.82 X 10-4 9.57 X 10-4 Q.Y. 2.93 X 10-4 3.19 X 10-4 3.72 X 10-4 3.62 X 19-4 % Degradation 95% 100% ICAME-2017 Yildiz University

Effect of light intensity on the photodegraation process Effect of radiation intensity on the photo-degradation rate on 10 ppm contaminant   1.90 mW/cm2 5.12 mW/cm2 8.78 mW/cm2 19.0 mW/cm2 T.N. 6.96 X 10-4 1.5 X 10-3 1.58 X 10-3 1.73 X 10-3 Q.Y. 1.42 X 10-3 1.35 X 10-3 6.57 X 10 -4 3.07 X 10-4 % Degradation 54% 95% 96% 100% Effect of radiation intensity on the photo-degradation rate on 20 ppm contaminant 7.96 X 10-4 1.86 X 10-3 1.99 X 10-3 2.38 X 10-3 1.62 X 10-3 1.41 X 10-3 8.76 X 10-4 4.28 X 10-4 34% 58% 65% 70% ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Catalyst re-use experiments   Fresh ZnO 1st re-use 2nd re-use T.N. 2.87 X 10-3 2.60 X 10-3 2.44 X 10-3 Q.Y. 5.44 X 10-4 4.90 X 10-4 % Degradation 84% 82% 78% ICAME-2017 Yildiz University

Complete mineralization ICAME-2017 Yildiz University

ICAME-2017 Yildiz University Thank You ICAME-2017 Yildiz University