Why does the luminous intensity of a colloidal quantum dot LED degrade with successive IV measurements?

More Ramesh Vasan's questions See All

I want know is there any code/program which give the count of Vehicle (Moving object) in matlab?

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One way or Two way ANOVA?

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08 November 2020 192 3 View

Here we are fabricating Perovskite solar cell in air atmosphere, even for standard cell also not getting PCE more than 1.5% but in reports PCE is 15%?

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Best techniques available for the VOCs adsorption by MOFs?

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The ratio of hypocholesterolemic/hypercholesterolemic (h/H) fatty acids?

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Physics: Why do we describe light by referring to its wavelength, but microwaves and radar pulses by referring to their frequency?

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Is there any effect of different colours of light (white, red, yellow, blue etc.) on the rate of photosynthesis? If yes, why?

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Gas sensor response and recovery time independant of flow rate and chamber volume?

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Tzu-Huan Cheng

Have you saw any red shift of EL spectrum or carrier lifetime change? It might be ion diffusion during measurement.

Ramesh Vasan

I did not see a red shift. The EL is same as the PL.

What are these ions, metal?

Is there a way to overcome this problem?

The emission might come from band edge emission or defect related emission. The Cd/Zn inter-diffusion might occur at high temperature. Have you check the junction temperature or IV curve with each trial? To reduce this degradation, you can try to measure EL with lower current level, pulse current source, or better heat sink for reducing joule heat. Hope it can work for your device.