Download High Conductivity UNCD films : Synthesis and Applications of

High Conductivity UNCD
films : Synthesis and
Applications of
I-Nan Lin 林諭男
Department of Physics,
Tamkang University, Tamsui
淡江大學物理系
[email protected]
IPLAS CVD SYSTEM
MCD
UNCD
OUTLINE
 Background

Synthesis of UNCD
 High conductivity UNCD films
 N2- plasma grown UNCD (N-
UNCD)
 Nanostructured UNCD films
 Application of UNCD
Electron field emitters
 Bio- and chemical - sensors

 Conclusion
OUTLINE
4
1
IPLAS CVD SYSTEM
UNCD
MCD
Background
Advantages & Applications of Diamond/UNCD
Good Electron field emission properties (Field emission display)
Highest surface acoustic wave velocity (SAW devices)
Highest thermal conductivity (Heat sink for LED and other devices)
Optical property, Highest hardness & Electrochemical electrodes, etc.
Nanodiamond
probes
RF MEMS Switch
Field Emission
(imaging)
RF MEMS
Resonator
UNCD seals
SAW Device
3D Structures
UNCD Wafer
Ref. www.thindiamond.com
6
IPLAS CVD SYSTEM
MCD
UNCD
Background
Advantages & Applications of UNCD
Enhanced properties as compared to micro-diamond
Device compatible surface smoothness (No polishing is required!)
….. many more……….
UNCD (CH4/Ar)
MCD (CH4/H2)
Micron to
Ultranano grains
HRTEM
7
2
IPLAS CVD SYSTEM
UNCD
MCD
Background
Growth
species
Microstructure
(Grain size)
Surface
roughness
Electronic
bonding
Hydrogen
content
Microcrystalline
Ultrananocrystallin
diamond (MCD)
e diamond (UNCD)
CH3 (CH4/H2 plasma) C2 (CH4/Ar plasma)
Columnar
(0.5–10 m)
400 nm–1 μm
Equi-axed
(2–10 nm)
< 40 nm
sp3
2–5% sp2
<1%
<1%
4
IPLAS CVD SYSTEM
UNCD
MCD
Background
How are UNCD Films Grown ??
New microwave
plasma
technology
OES
C2
Ar
Ar/CH4 Plasma
8
3
IPLAS CVD SYSTEM
UNCD
MCD
Background
UNCD Growth Mechanism
UNCD films grown using
Ar(99%) /CH4 (1%) plasmas
C2H2
1
(C2 Chemistry)
Thermal
Dissociation
of CH4
2
H2
H0
C2 Dimer Nucleation
C2
Ar
CH3
C2 Dimer
Formation
C2 dimers form sp3-bonded carbon (diamond) with
Low activation energy (6 kcal/mol)
High secondary-nucleation rate (1010 /cm2)
•
•
Ref. D. M. Gruen, et. al., Ann. Rev. Mater. Sc. 29, 211 (1999)
9
IPLAS CVD SYSTEM
MCD
UNCD
Introduction
Nucleation Stage
Requirements
• Nucleation density
• Secondary nucleation
• Adhesion
• Grain size
• Diamond structure
Seeding Technique
–
–
–
–
–
Mechanical abrasion
Ultrasonication
Bias enhanced nucleation (BEN)
Diamond powder seeding
Intermediate layer: DLC, carbide metal
Ref.: R. Stöckel et al., J. Appl. Phys. Vol. 83, 1 (1998)
10
4
IPLAS CVD SYSTEM
MCD
UNCD
Introduction
Nucleation Stage
Scratched
Ultrasonication (U)
Spin Coating
(diamond slurry)
 Pre-nucleation
treatment of substrates is
important for the growth of continuous and
very smooth UNCD films.
Ultrasonication (U-m)
(diamond/Ti mixture)
Pre-Carburize + U
(PC-U)
Bias enhanced nucleation
(BEN)
11
IPLAS CVD SYSTEM
MCD
UNCD
Background
Growth & Characterizations
* NEXAFS
FESEM
HRTEM
*
282 284 286 288 290 292
Binding energy (eV)
G
AFM image
3
G'
D
1
Grain size ~510 nm
Roughness < 2nm
Intensity (arb. units)
UNCD Deposition
MW Power: 1200 W
Press: 120 Torr, CH4/Ar (1:99)
Substrate temp. ~460oC
XPS
C1s
1100 1200 1300 1400 1500 1600 1700
-1
Raman shift (cm )
13
5
IPLAS CVD SYSTEM
MCD
UNCD
OUTLINE
 Background
Synthesis of UNCD
 High conductivity UNCD films
 N2- plasma grown UNCD (NUNCD)
 Nanostructured UNCD films
 Application of UNCD
 Electron field emitters,
microplasma cathode
 Bio- and chemical – sensors
 Conclusion

UNCD applications
4
IPLAS CVD SYSTEM
MCD
UNCD
Conclusion
 Synthesis of high conductivity
UNCD :
 Microstructure control (N2/CH4 plasma; 2-step MPE-CVD
 Nanostructuring (templates, RIE)
 Application of UNCD
 Electron souces
• Electron field emitters;
• Microplasma electrodes

conclusion
Bio- and chemical sensors
• Dopamine, NADH, Urea,
• Heavy metal, Amitrole
6
7
Microstructure
Effect
of (Ar-%H2)/Ar plasma.
H2 0%
H2 80%
control for UNCD:
samples
plasma
CH4/Ar/H2 ratio
1:(99-x):x
x=0, 1.5, 2.5 …
20, 30…..…80
ultrasonicating
100 Torr
1200 W
3h
Seeding Method
Pressure
Power
Growth time
13
SEM
H2 0%
H2 1.5%
H2 2.5%
H2 3.5%
H2 5%
H2 8%
H2 10%
H2 20%
H2 30%
H2 40%
H2 50%
H2 80%
1
Normalized Absorption (a.u.)
15
NEXAFS
0 H2
1.5 H2
2.5 H2
3.5 H2
5 H2
8 H2
10 H2
12
9
(Near edge x-ray absorption
spectroscopy)
6
3.5
3
0
270
15% H2
20% H2
30% H2
40% H2
320
50% H2
80% H2
3.0
280
290
2.5
310
2.0
300
Photon Energy (eV)
1.5
1.0
0.5
0.0
280
290
300
310
320
Photon Energy (eV)
10000
Raman
spectroscopy
8000
6000
4000
100000
2000
80000
1000
1200
1400
Intensity (a.u.)
Intensity (a.u.)
UV Raman (244 nm)
1600
80 H2
60 H2
50 H2
40 H2
30 H2
20 H2
15 H2
10 H2
8 H2
5 H2
3.5 H2
2.5 H2
1.5 H2
0 H2
1800
Visible (514 nm )
80 H2
60 H2
2000
50 H2
40 H2
-1
Raman shift (cm 60000
)
30 H2
20 H2
15 H2
10 H2
8 H2
5 H2
3.5 H2
0 H2
40000
20000
0
1000
1200
1400
1600
-1
1800
200
Raman shift (cm )
2
EFE
0.6
0% 22.13
1% 23.16
H2 3.5%
2% 25.56
3% 25.72
H2 0%
H2 5%
5% 27.78
H2 2.5%
8% 28.37
10% 30.33
15% 32.38
20% 39.10H 1.5%
2
30% 50.01
40% 55.00
2
J (mA/cm )
0.5
0.4
0.3
0.2
0.1
H2 10%
H2 20%
H2 40%
0.0
H2 8%
-0.1
0
50
H2 30%
100
E (V/m)
H2 0%
H2 1.5%
H2 2.5%
H2 3.5%
20 nm
100 nm
100 nm
500 nm
H2 5%
H2 8%
H2 10%
H2 20%
500 nm
500 nm
500 nm
500 nm
H2 30%
H2 40%
H2 50%
H2 80%
500 nm
1000 nm
500 nm
500 nm
TEM
3
(Optical Emission spectroscopy)
OES
7000
Intensity (a.u.)
6000
H Ar
C2
H
100% H2
80% H2
60% H2
50% H2
40% H2
30% H2
20% H2
15% H2
10% H2
8% H2
5% H2
0% H2
5000
4000
3000
2000
1000
0
400
500
600
700
800
Wavelength (nm)
H2plasma
CH3+ & Atomic H
H2 80%
Large
faceted
grains
4
Arplasma
C2-dimers
C2-dimers+H
Spherical
grains
Ar-H2
plasma
Acicular grains
To enhance the EFE properties of UNCD films

Use UNCD films [CH4/Ar
plasma] as the nucleation
layer

the growth of MCD films
[CH4/(50%Ar-50%H2
plasma]
5
Hybrid granular structured (HiD) diamond films: NCD/UNCD
JOURNAL OF APPLIED PHYSICS 109, 033711 (2011)
N-ion implanted HiD diamond films
Electron Energy Loss
Spectroscopy
6

High conductivity UNCD
I. Hybrid diamond
 II. Semiconductor doing of UNCD.
 III. CH4/N2 – Plasma (at 700℃).
 IV. Nanostructuring
• nanostructure templates
• RIE etching


II. Semiconductor doing of UNCD
 N, C, B-ion implantation.
Implanted
ion
Ion energy
(keV)
Dosage
(Ions/cm2)
Nitrogen (N)
Boron (B)
Carbon (C)
100
130
130
11015
11015
11015
Ion implantation &
annealing
E0 (V/m)
J (mA/cm2)
9.2
1.54
8.8
5.42
11.3
1.17
10.7
0.13
 N, C, B-ion implantation.
 Ag- and Au- ion irradiation.
 Au and Cu-ion implantation.
 Au-ion implantation on UNCD-Au_Si
1
Enhancement in electron field emission in ultrananocrystalline and microcrystalline diamond films upon
100 MeV silver ion irradiation JOURNAL OF APPLIED PHYSICS 105, 083707 2009
 Melting and recrystallization process have occurred
along the trajectory of the heavy ions.
 Such a process induced the formation of interconnected
nanocluster networks, facilitating the electron conduction
and enhancing the EFE properties for the materials.
Effect of 2.245 gigaelectron volt Au-ion irradiation on the
characteristics of ultrananocrystalline diamond films
J. Appl. Phys. 108, 123712 (2010), & AIP Advances, 2011

Formation of nanographites along the
trajectory of the irradiating ions.
 Nanographite formed an interconnected
path for electron transport that facilitated
the EFE process.
2
Ag & Au Ion-irradiation on UNCD films
How about directly ion implantation ???
Gold and Copper ion implantation induced high conductivity and
enhanced electron field emission properties in ultrananocrystalline
APPLIED PHYSICS LETTERS 102, 061604 (2013)
diamond films
Cu-implanted UNCD
Au-implanted UNCD
 The formations of Cu and Au nanoparticles and the introduction of
nanographitic phases among the diamond grains advance the conducting
nature of the films,
 Enhancing the EFE properties of the Cu and Au implanted UNCD films.
3
Gold ion implantation on UNCD films using
Au as interlayer
Ion
Dosage Ion implantation & annealing
energy (Ions/cm2)
J
E0

(keV)
( cm)-1 (V/m) (mA/cm2)
9.2
1.54
15
100
110
200
8.8
5.42
0.3
8.2
3.3
300
11017
17
185
4.88
1.17
500
110
Implanted ion
N/UNCD/Si
Cu/UNCD/Si
Au/UNCD/Si
Au
Au
Au
Au
Au
Au
Au
Au
Au
Au
Au
Au
Au
UNCD
Si
Au
Au
Au
Au
Au
Au
Au-implt UNCD/Si
Si
UNCD/Au-Si
Au
Au
Au
Au
Au
UNCD
UNCD
Au
Au
Au
Au
Si
Au-impt UNCD/Au-Si
Gold ion implantation on UNCD/Si films using Au as
interlayer
Expansive apparatus ??
Expansive apparatus ??
Expansive apparatus ??
Expansive apparatus ??
Expansive apparatus ?
Expansive apparatus
4
 III. CH4/N2 – Plasma (at 700℃).
Origin of needle-like granular structure for ultrananocrystalline
diamond films grown in CH4/N2 plasma J. Phys. D: Appl. Phys. 45 (2012)
Structural and Electrical Properties of Conducting N-UNCD films
ACS Appl. Mater. Interfaces 2013, 5, 1294
 High conducting grain boundaries of N-UNCD
films (700C) demonstrates a high efficiency in
field emission.
5
Arplasma
C2-dimers+CH
C2-dimers+CN
Spherical
grains
 CH4/N2
Ar-N2
plasma
Needle-like
grains
– Plasma (at 700℃)
 IV. Nanostructuring UNCD
• High conductivity UNCDfilms
• nanostructure templates
• RIE etching
6
On the enhancement of field emission performance of
ultrananocrystalline diamond coated nanoemitters
Appl. Phys. Lett. 91 (2007) 063117
Nanotechnology, 18 (2007) 435703
Electron Field Emission Enhancement of Vertically Aligned
Ultrananocrystalline Diamond-Coated ZnO Core–Shell Heterostructured
small 2013
Nanorods
ZnO nanorods
UNCD/ZnO nanorods
Introduction of graphitic
phases in the interface
region between the ZNRs
and UNCDs layer
 lowers the resistivity
of the interfacial layer.
7
Investigations on Diamond Nanostructuring of Different Morphologies by
the Reactive-Ion Etching Process and Their Potential Applications
ACS Appl. Mater. Interfaces 2013, 5, 7439
NCD
MCD
N-UNCD
UNCD
 Nanostructuring of diamond is a function
of the initial diamond morphology, the
phase composition of the diamond, the
mask size, and the etching time.
 The enhanced EFE properties are
observed for N-UNCD nanograss.
8
Application of high conductivity
UNCD films

Electron sources

Bio- & Chemical sensors
 EFE flat panel display,
 Microplasms electrodes
 Blood testing
• Dopamine, NADH, Urea
 Water monitoring
• Heavy metal; Amitrole
Field Emission Flat Panel Display
(EF-FPD)
Advantages:





Thin, lightweight emissive display
Bright and efficient
Wide viewing angle
Video speed
Wide operating temperature range
1
Enhancing the plasma illumination behaviour of microplasma
devices using microcrystalline/ultrananocrystalline hybrid
Nanoscale, 2013, 5, 7467
diamond materials as cathodes
Flexible EFE Emitters Fabricated Using Conducting
UNCD Pyramidal Microtips on Polynorbornene Films
2
High Stability Electron Field Emitters made
of NCD coated Carbon Nanotubes (CNTs)
Microplasma
Neutral
Atoms
Negative
Electrons
Positiv
e Ions
3
 Cathode
materials for
microplasma:

diamond coated Si-tips.
Fabrication of diamond coated Si-nanotips
1. Lithography
2. Reactive ion etching
3. Removal of PR
5. Growth of UNCD
4. Deposition of Au film
4
Diamond coated Si-nanotips as cathode
 UNCD/Au/Si
(CH4/Ar=4/196 sccm)
 Si
(a) Si pyram.
(a) UNCD/Si
(c) UNCD/Au/Si-pyram.
100 nm
4 m
 UNCD/Si
(CH4/Ar=4/196 sccm)
(b) UNCD/Au-Si
4 m
1m
1m
 (MCD/UNCD)/Au/Si
(CH4/Ar=4/196 sccm;
CH4/[49%Ar+50%H2])
(b) UNCD/Si-pyram.
(d) MCD-UNCD/Au/Si-pyram.
100 nm
(c) MCD‐UNCD/Au/Si
4 m
4 m
1m
1m
Electron field emission &
plasma illumination
100 nm
(a) Si-tips
200V
210V
220V
230V
240V
250V
260V
270V
280V
290V
300V
310V
320V
330V
340V
350V
200V
210V
220V
(c) UNCD/Au/Si-tips
230V
200V
210V
220V
240V
250V
260V
(d) MCD-UNCD/Au/Si-tips
200V
210V
220V
250V
240V
260V
300V
280V
290V
230V
270V
230V
270V
310V
240V
280V
320V
250V
290V
330V
260V
300V
340V
270V
310V
350V
280V
320V
290V
330V
300V
340V
310V
350V
320V
330V
340V
350V
 Si-tips
 UNCD/Si-tips
(CH4/Ar=4/196 sccm)
 UNCD/Au/Si-tips
(CH4/Ar=4/196 sccm)
3.2
2.8
2.4
2.0
1.6
1.2
0.8
0.4
(i) Si-pyramid
(ii) UNCD/Si-pyramid
(iii) UNCD/Au/Si-pyramid
(iv) MCD-UNCD/Au/Si-pyramid
ln(J/E2)((mA/cm2)/(V/m)2)
Current Density (mA/cm2)
 MCD/UNCD/Au/Si (CH4/Ar=4/196 sccm;
CH4/[49%Ar+50%H2])
0.0
-30
0
-1
-2
-3
-4
-5
-6
-7
-8
-9
(iv) (iii)
(ii)
(i)
0.0 0.4 0.8 1.2 1.6 2.0 2.4 2.8 3.2
1/E (m/V)
-20
-10
0
10
20
30
40
(b) UNCD/Si-tips
Electric Field (V/m)
5
6
(ii) UNCD/Si-pyramid
(iii) UNCD/Au/Si-pyrmid
(iv) MCD-UNCD/Au/Si-pyramid
(ii) UNCD/Si-pyramid 4
(iii) UNCD/Au/Si-pyrmid
2
6 (iv) MCD-UNCD/Au/Si-pyramid
(iv)
(iii)
(ii)
240
280
320
(i))
Electric Field (V/mm

2
(․cm)-1
(a) Si-tips
(iv) MCD-UNCD/Au/Si-pyramid
0.6
0.4
(iv)
(iii)
(ii)
0.2
(i)
0.0
-0.2
360
0
2000
4000
6000
8000
Time (seconds)
EFE
Plasma
(Eth)pl. Jpl.
E0
Je
(V/m)
(mA/cm2)
(V/mm)
(mA/cm2)
230
3.8
<0.01
0.04
210
5.9
0.05
210
6.5
3.40
200
7.8
(c) UNCD/Au/Si-tips
tips
330V
340V
350V
340V
350V
(b) UNCD/Si-tips
320V
(ii)
(i)
20.00
Si-tips0
UNCDSi-tips
200
240
280320 11.60360
0.78(V/mm) 9.23
UNCDAu/Si-tips Electric Field
24.0
5.99
MCD/UNCDAu/Si320V
0.8 (iii) UNCD/Au/Si-pyrmid
(iii)
0
200
4
(i) Si-pyramid
(ii) UNCD/Si-pyrmid
(iv)
Current (mA)
Current Density (mA/cm2)
Current Density (mA/cm2)
8 (i) Si-pyramid
1.0
8 (i) Si-pyramid
330V
320V
330V
340V
350V
(d) MCD-UNCD/Au/Si-tips
320V
330V
340V
350V
 Plasma
illumination
characteritics of cylindrical
microplasma using HiD as
cathodes
6
Cylindrical microplasma devices
(a) KOH
etch
SiO2
(a)
6.12 μm
Silicon
(c) Formation of cylindrical
cavities
(i) SiN patterning (ii) Dry Etch
HiD
HiD
50μm
Cu/Ag
HiD
1 m
100 m
(b)
Silicon
1 m
1 μm 150 μm
(d) DC
pulse
+
Bipolar Pulse-Mode
2 m
3.0
2.5
0
1
2
3
4
5
2.0
1.5
1.0
0.5
6
1/E (cm/V)
ln(J/E2) (A/V2)
2
475 μm
100 m
Current density (mA/cm )
Silicon
(iii) KOH Etch
-3
-4
-5
-6
-7
-8
-9
-10
-11
-12
II
I
I.Planar HiD
II.HiD array
2.7
0.0
0
2
3.75
4
6
8
10
Electric field (V/m)
12
Plasma illumination characteistics
7
 Why
HiD films?
 Life
stabilits of HiD cathodes
for microplasma devices
Plasma Current (A)
540
480
420
360
300
240
N-UNCD/Au-Si
MCD-UNCD/Au-Si
UNCD/Au-Si
180
120
350
400
450 500 550
Voltage (V)
600
650
700
8
Application of high conductivity
UNCD films

Electron sources

Bio- & Chemical sensors
 EFE flat panel display,
 Microplasms electrodes
 Blood testing
• Dopamine, NADH, Urea
 Water monitoring
• Heavy metal; Amitrole
DNW (N-UNCD) as Electrochemical
Bio- and chemical sensor
Electrochemical (EC) Sensing Applications
Using conductive UNCD films
Biosensor
9
Analytes:
1. Dopamine
2. NADH
3. Urea
NADH in Krebs Cycle:
citric-acid cycle
Conversion of proteins, carbohydrates
and fats into ATP (Energy)
Deficiency  Alzheimer’s disease
In the brain, Dopamine functions as
a neurotransmitter—a chemical
released
by nerve cells to send signals to other
nerve cells  Parkinson's disease.
Dopamine pathway in Brain
 Urea ((NH2)2CO) is basically
an organic compound deal
with the excretion of
nitrogen waste from protein
and amino acid catabolism.
 The normal level of urea in
serum is from 1.7-8.3 mM.
 An increase blood and
urine causes renal failure,
urinary tract,
gastrointestinal bleeding.
 Reduced urea level results
in hepatic failure, nephritic
s ndrome and cache ia
DNW (N-UNCD) as Dopamine sensor
10
In situ Detection of Dopamine using Nitrogen
Incorporated Diamond Nanowire Electrode
Nanoscale 5 (2013) 115
C=N
C-N
C=N
C-N
C=C
C-C
700
C-C
C=C
100 nm
100 nm
(d) 800 C
(c) 700 C
800 oC
oC
286
600oC
550oC
nd
2 diamond gap
288
290
282
284
286
B.E (eV)
288
0.00004
Current (A)
0.003
0.000
550 C
-0.003
600 C
700 C
-0.009
800 C
Graphite
-3
-2
-1
0
1
2
Electrode
0.00000
550C
600 C
700 C
800 C
-0.00004
-0.00006
3
-0.1
0.0
Potential (V)
0.1
0.2
0.3
0.4
ΔEp
(mV)
175
90
95
210
98
DNWs-550
DNWs-600
DNWs-700
DNWs-800
Graphite
BDD
0.00002
-0.00002
-0.006
310
0.5
Potential (V)
Ipa/ Ipc
(µA)
ASA – Active surface area
Conductivity
ASA
(Ω-cm)-1
(Cm2)
1.16
0.98
0.90
1.10
0.82
1.2
106
186
90
106.9
0.217
0.254
0.250
0.132
0.202
Differential pulse Voltammetry
157 mV
0.000010
0.0000075
UA
0.0000060
125.8 mV
0.0000045
-0.2 -0.1 0.0
0.1
0.2
0.3
0.4
0.5
-0.2


Current (A)
138 mV
AA
-0.2
0.000085
0.1
0.2
0.3
Potential (V)
0.4
0.5
0.6
DA
286.1 mV
AA
0.1
0.2
0.3
Potential (V)
0.4
0.5
AA
DA
0.000065
-0.2
0.0
-6
0.2
0.4
0.6
Potential (V)
Boron Doped Diamond
3.0x10
304.2 mV
0.000015
0.0
0.6
0.000070
3.5x10
138.2 mV
0.000020
0.000010
-0.2 -0.1 0.0
0.4
0.000075
-6
UA
0.2
(b) Glassy Carbon
0.000080
0.000060
0.000025
0.0
Potential (V)
0.000090
167.7mV
-0.1
0.0000003
0.0000000
(d) 800C
0.000012
DA
0.0000006
0.000006
0.000030
148.5 mV
0.000008
131.2 mV
0.000035
UA
0.000010
0.000008
-0.2 -0.1 0.0
0.6
0.000016
0.000014
164.6 mV
(a) Graphite
0.0000009
0.000004
Potential (V)
DA
(c) 700C
UA
AA 293.5 mV
284.6 mV
0.000018
0.0000012
DA
Current (A)
AA
0.0000030
(b) 600C
Current (A)
0.000012
Current (A)
Current (A)
DA
(a) 500C
0.0000090
Current (A)
0.0000105
Current (A)
Current (A)
0.00006
300
Energy (eV)
290
Cyclic Voltammetry
0.006
290
100 nm
100 nm
B.E (eV)
700oC
280
C-N
C-N
284
800oC
*
C=N
C=N
282
NXAFS
*
C-C
C=C
C=C
600 oC
550 oC
(b) 600 C
C-C
Intensity (arb. units)
Intensity (arb.units) Intensity (arb.units)
XPS
(a) 550 C
-6
2.5x10
-6
2.0x10
AA
-6
1.5x10
DA
-6
1.0x10
0.1
0.2
0.3
Potential (V)
0.4
0.5
0.6
-0.2
-0.1
0.0
0.1
0.2
0.3
0.4
0.5
Potential (V)
The DNW electrodes show excellent electrocatalytic activity towards
the oxidation of small molecules, such as AA, DA, and UA.
High selectivity and reliable antifouling ability are superior to glassy
carbon (GC) or boron-doped diamond (BDD).
11
0.00004
Detection
limit
0.231
700 C
2.0
1.8
0.224
0.210
Current (A)
0.00001
1.6
0.207
0.203
0.196
0.00000
0
100
200
300
400
500
600
700
COOH-BDD electrodes
GC electrode
(AuNP Attachment)
GC electrode
- poly (p-nitrobenzenazo
resorcinol)modified
Graphite Pencil Electrode
- Poly (Eriochrome Black T)
Film Modified
DNW film (700 °C)
0.201
0.198
0.195
0.192
0
0.189
0
Time (S)
Electrode
1.4
0.204
Current (A)
Current (A)
0.00002
0.217
100
200
2
4
6
8
Concentration (
300
400
Concentration (
1.4
1.2
1.2
1.0
1.0
Current (A)
Current (A)
0.00003
10
500
DA
dynamic
range (µM)
0-30
DA
detection limit
(µM)
0.1
20-145
0.8
AA
(mM)
UA
(mM)
0.5
-
-
1.5
-
5-25
0.39
1.1
0.13
0.1-0.3 × 10−3
0.08
-
1 × 10−3
0.5-500
0.34
0.5
0.005
DNW (N-UNCD) as NADH sensor
12
Mediatorless N2 Incorporated Diamond Nanowire
Electrode for Selective Detection of NADH at
Stable Low Oxidation Potential
Cyclic Voltammetry
3.1
BDD
DNW
3.0
log Current (Ip)
Current (A)
0.00012
2.9
2.8
0.00008
Slope= 0.48
2.7
2.6
2.5
1.2 1.4 1.6 1.8 2.0 2.2 2.4
log Scan rate ()
0.00004
0.00000
-0.00004
-1.0
-0.5
0.0
0.5
1.0
Potential (V)
 The combination of long-term
stability, high reproducibility
and low operating potential of
N-DNW films are superior to
previous reports.
5.1
4.8
4.5
4.2
3.9
3.6
3.3
3.0
2.7
2.4
y = 0.127x + 0.2408
R?= 0.9981
NADH
500 M
-6
5.0x10
Current (A)
Current (A)
Detection limit and Stability
Schematic representation of
NADH & AA Detection
-6
4.0x10
-6
3.0x10
0.5 M
-6
2.0x10
AA
-6
1.0x10
2.1
y = 0.0264x + 1.8323
-0.4
-0.2
0.0
0.2
0.4
0.6
Potential (V)
R?= 0.983
1.8
0
100 200 300 400 500 600 700 800
Concentration (M)
0.00003
After 20 days
Fresh
0.00000
Current (A)
Current (A)
0.00006
DNW
-0.00003
-0.00006
8.0x10
-5
4.0x10
-5
Fresh
0.0
-4.0x10
BDD
After 20 days
-5
-1.0
-1.0
-0.5
0.0
-0.5 0.0 0.5
Potential (V)
0.5
1.0
1.0
1.5
Potential (V)
Electrode
N-UNCD Nanowire
electrode
Detection
range
0.5 – 500
µM
Oxidation
potential
+ 0.15 V
 The
range, sensitivity &
detection limit of the N-DNW
sensor are compared
favorably with values for
other electrode systems.
13
DNW (N-UNCD) as Urea sensor
An Amperometric Urea Bisosensor based on
Covalent Immobilization of Urease on (N-DNW)
Electrode

N-DNW electrode is wetchemically cleaned
(oxidation) by boiling in
a mixture of H2SO4 and
HNO3 (3:1) at 200 °C for 2
h to remove graphite.

Urs and GLDH are
covalently attached to
the oxidized N-DNW
electrode by activating
the COOH group of NDNW using EDC as the
coupling agent and NHS
as activator.
14
Urea Biosensors
 The developed N-DNW Electrode biosensor exhibited good performance in
sensitivity, stability and reproducibility.
 Urs-GLDH/N-DNW exhibited linear and stability.
 Urs-GLDH/N-DNW bio-electrode retained 80% of its initial enzyme activity
for 1 month, when stored at 4–6 °C in a refrigerator.
CHEMICAL SENSORS
Industrial waste greatly affect the Environment
in terms of water, soil, air
Soil and Air pollution


Water pollution
DNW (N-UNCD) in Heavy Metal Detection
DNW (N-UNCD) as Nicotine Sensor
15
DNW (N-UNCD) in Heavy Metal Detection
Selective and Simultaneous Detection of Toxic
Metal Ions using Samarium Hexacyanoferrate
(SmHCF) Modified Diamond Nanowire Electrode
Simultaneous detection of Lead(pb), Cadmium(Cd), Zinc (Zn), Copper (Cu), Mercury (Hg)
 SmHCF was prepared
electrochemically on
the surface of DNW
electrode (SmHCF/
DNW) .
 The interference between Zn2+, Cd2+, Pb2+, Cu2+ and Hg2+ were studied by using
SmHCF/DNW film electrodes in a solution containing a mixture of with and
without five analytes.
16
DNW (N-UNCD) as Amitrole (Pesticide) sensor
Selective Detection of Amitrole( pesticide) using
Gold Interlayered Diamond Nanowire Electrode
70 µm
10 µm
-4
1.0x10
60 µm
-5
Current (A)
8.0x10
Glassy carbon
N-UNCD/Au/Si
N-UNCD
-5
6.0x10
-5
4.0x10
-5
2.0x10
0.0
0.5 µm
-5
-2.0x10
-0.2
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Potential (V)
17
Potential Applications

Biosensors (chemical sensors ) play a part
in the field of environmental quality,
medicine and industry mainly by
identifying material and the degree of
concentration present.
18