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Topic: emissions spectrum cdse nanoparticle  (Read 4208 times)

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Offline Plumbum

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emissions spectrum cdse nanoparticle
« on: November 19, 2015, 10:47:35 AM »
hey guys

can somone pls help me ? I was wondering why the first peak in this graph looks different from the others? what i mean is that, the graph doesnt drop until the end.

I hope somebody understands what i mean:) thank you.
There might be some language misunderstandings - I'm from Germany

Offline Arkcon

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Re: emissions spectrum cdse nanoparticle
« Reply #1 on: November 19, 2015, 11:24:15 AM »
Ok.  What were you expecting, and why?

Sorry to answer a question with a question.  But that's how people learn on this forum.
Hey, I'm not judging.  I just like to shoot straight.  I'm a man of science.

Offline Plumbum

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Re: emissions spectrum cdse nanoparticle
« Reply #2 on: November 19, 2015, 11:44:42 AM »
i was expecting the peak to drop until 0 just like the other peaks. The first peak must be the nanoparticle with the smallest diameter.
There might be some language misunderstandings - I'm from Germany

Offline Corribus

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Re: emissions spectrum cdse nanoparticle
« Reply #3 on: November 19, 2015, 01:35:05 PM »
This is commonly observed in core-only QDs due to the presence of surface defects that act as trap sites. Usually it is more common to observe in blue-emitting dots. Can you think of why?
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline Plumbum

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Re: emissions spectrum cdse nanoparticle
« Reply #4 on: November 19, 2015, 04:43:07 PM »
i don't know but maybe because the particels are smaller ?
There might be some language misunderstandings - I'm from Germany

Offline Corribus

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Re: emissions spectrum cdse nanoparticle
« Reply #5 on: November 19, 2015, 05:25:52 PM »
Right, they are smaller so..
(hint: surface defects)

(Here is an open access review on QDs that you might find useful; check out figure 1. Materials 2010, 3, 2260-2345; doi:10.3390/ma3042260. Direct link.
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline Plumbum

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Re: emissions spectrum cdse nanoparticle
« Reply #6 on: November 20, 2015, 06:08:26 AM »
what i wanted to say with small is that the defects seem to be bigger than when the surface of the particl is bigger (hope you know what i mean?)

interesting paper, thank you
There might be some language misunderstandings - I'm from Germany

Offline Plumbum

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Re: emissions spectrum cdse nanoparticle
« Reply #7 on: November 20, 2015, 06:29:44 AM »
hey, i have no experience at all with this whole topic.Can you take a look at my graphes and tell me whether they are fine :D?
I think its quite obvious which one is absorption and which one is emission :)

thank you
There might be some language misunderstandings - I'm from Germany

Offline Corribus

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Re: emissions spectrum cdse nanoparticle
« Reply #8 on: November 20, 2015, 09:18:21 AM »
As a sort of simple explanation, I would say that smaller particles have larger relative surface area, which means it is more likely that smaller particles have surface defects than larger particles.

It is frankly difficult to make out the plots you showed. What do you mean by "fine"? What do you want them to show?
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

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