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Detection of gunshot residue and explosives using hybrid graphene/quantum dot based sensors

de Geer, Elsa LU (2017) PHYM01 20161
Solid State Physics
Department of Physics
Abstract
This master thesis investigates the use of chemically exfoliated graphene,
CdSe/CdS/ZnS quantum dots and graphene quantum dots for fluorescence
based detection of gunshot residue and explosives. Specifically, nitroglycerine
is chosen as the target substance in gunshot residue and the nitroaromatic
compounds trinitrotoluene and dinitrotoluene are chosen as target explosives.

The experimental work is divided into three part were the first one is an
investigation of the quenching of semiconductor quantum dot fluorescence by
graphene. The results show that graphene is an efficient quencher, and it is
probable that quenching takes place without the fluorescing and quenching
agents being in contacts, through either Förster resonance... (More)
This master thesis investigates the use of chemically exfoliated graphene,
CdSe/CdS/ZnS quantum dots and graphene quantum dots for fluorescence
based detection of gunshot residue and explosives. Specifically, nitroglycerine
is chosen as the target substance in gunshot residue and the nitroaromatic
compounds trinitrotoluene and dinitrotoluene are chosen as target explosives.

The experimental work is divided into three part were the first one is an
investigation of the quenching of semiconductor quantum dot fluorescence by
graphene. The results show that graphene is an efficient quencher, and it is
probable that quenching takes place without the fluorescing and quenching
agents being in contacts, through either Förster resonance energy transfer or
nanometal surface energy transfer.

The second part is a study of how nitroaromatic molecules quench the
fluorescence from graphene quantum dots. The results indicate that the
solvent of the nitroaromatics passivates the functional groups which reduces
the quenching efficiency. Nevertheless, it is concluded that the nitroaromatics
quench the fluorescence. It is possible that the quenching mechanism is
photoinduced charge transfer.

The last part of the experimental work investigates the influence of
nitroaromatics on the graphene and semiconductor quantum dot hybrid from
the first part. It is shown that nitroaromatics further quench the fluorescence
of the quantum dots in the hybrid structure, possibly by photoinduced charge
transfer or by reacting with the surface coating of the quantum dots and
thereby introducing de-excitation through surface states. (Less)
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author
de Geer, Elsa LU
supervisor
organization
alternative title
Sensorer av grafen och kvantprickar för detektion av krutrester och sprängämnen
course
PHYM01 20161
year
type
H2 - Master's Degree (Two Years)
subject
keywords
Graphene, quantum dots, explosives, gunshot residue, fluorescence, quenching
language
English
additional info
Thesis work carried out at Acreo, Stockholm.
id
8898528
date added to LUP
2017-01-10 12:26:33
date last changed
2017-01-10 12:26:33
@misc{8898528,
  abstract     = {This master thesis investigates the use of chemically exfoliated graphene,
CdSe/CdS/ZnS quantum dots and graphene quantum dots for fluorescence
based detection of gunshot residue and explosives. Specifically, nitroglycerine
is chosen as the target substance in gunshot residue and the nitroaromatic
compounds trinitrotoluene and dinitrotoluene are chosen as target explosives.

The experimental work is divided into three part were the first one is an
investigation of the quenching of semiconductor quantum dot fluorescence by
graphene. The results show that graphene is an efficient quencher, and it is
probable that quenching takes place without the fluorescing and quenching
agents being in contacts, through either Förster resonance energy transfer or
nanometal surface energy transfer.

The second part is a study of how nitroaromatic molecules quench the
fluorescence from graphene quantum dots. The results indicate that the
solvent of the nitroaromatics passivates the functional groups which reduces
the quenching efficiency. Nevertheless, it is concluded that the nitroaromatics
quench the fluorescence. It is possible that the quenching mechanism is
photoinduced charge transfer.

The last part of the experimental work investigates the influence of
nitroaromatics on the graphene and semiconductor quantum dot hybrid from
the first part. It is shown that nitroaromatics further quench the fluorescence
of the quantum dots in the hybrid structure, possibly by photoinduced charge
transfer or by reacting with the surface coating of the quantum dots and
thereby introducing de-excitation through surface states.},
  author       = {de Geer, Elsa},
  keyword      = {Graphene,quantum dots,explosives,gunshot residue,fluorescence,quenching},
  language     = {eng},
  note         = {Student Paper},
  title        = {Detection of gunshot residue and explosives using hybrid graphene/quantum dot based sensors},
  year         = {2017},
}