No. 6 Investigation of MEH-PPV OLED Assisted by An IoT Environment Monitoring System

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Ibrahim Attia
Guang Liang Ong
Teng Sian Ong
Chen Hon Nee
Seong Shan Yap


Single layer organic light emitting diode (OLED) devices based on poly{[2-methoxy-5-(-2ethylhexyloxy)-1,4-phenylene]vinylene} (MEH-PPV) are fabricated and studied in this work. There are several factors that affect the performance of the fabricated OLED samples. Some of these factors are related to the fabrication parameters chosen for the OLED fabrication process. The effect of concentration and annealing temperature are investigated. Other environmental factors such as humidity or temperature affect the performance of fabricated OLED samples under long term exposure. An internet of things environment monitoring system (IoT-EMS) is developed to monitor and study the effect of these factors on the performance of the OLED samples. Exposure to humidity is found to severely degrade the samples. In summary, the optimum concentration for MEH-PPV is concluded to be 4 mg/ml, and the best annealing temperature is 90°C in this study. It is also deduced that humidity of 72-75 % caused degradation of the samples in less than 20 hours.

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