Synthesis and Characterization of Gold Nanoparticles Incorporated Bentonite Clay For

SUPPLEMENTARY INFORMATION

Synthesis and characterization of gold nanoparticles incorporated bentonite clay for electrocatalytic sensing of arsenic(III)#

PANKAJ KUMAR RASTOGI, DHARMENDRA KUMAR YADAV, SHRUTI PANDEY, VELLAICHAMY GANESAN*, PIYUSH KUMAR SONKAR and RUPALI GUPTA

Department of Chemistry, Center of Advanced Study, Faculty of Science, Banaras Hindu University, Varanasi 221 005, UP, India

e-mail: ;

Contents

Figure S1. EDAX spectrum of Au-bt.

Figure S2. CV responses of GC/Au-bt ESP at different scan rate in 0.1 M pH 7.0 PBS. Inset (i) shows the variation of anodic peak current with square root of scan rates and inset (ii) shows the variation of anodic peak current with scan rates.

Figure S3. Nyquist plots for GC/Au-bt ESP in absence (a) and presence (b to k) of various concentrations of As(III) at an applied potential of +0.60 V in 0.1 M pH 7.0 PBS.

Figure S4. CV responses obtained at GC/Au-bt ESP in 0.1 M PBS (pH 7.0) containing 250.0 µM As(III) (a) and containing 250.0 µM As(III) and 500.0 µM Cu(II) ions (b). Scan rate of 20 mVs-1.

Table S1. Comparison of some analytical characteristics of the present method with other reported methods for As(III) determination.

Figure S1

Figure S1. EDAX spectrum of Au-bt.

Figure S2.

Figure S2. CV responses of GC/Au-bt ESP at different scan rates in 0.1 M pH 7.0 PBS. Inset (i) shows the variation of anodic peak current with square root of scan rates and inset (ii) shows the variation of anodic peak current with scan rates.

Figure S3.

Figure S3. Nyquist plots for GC/Au-bt ESP in absence (a) and presence (b to k) of various concentrations of As(III) at an applied potential of +0.60 V in 0.1 M pH 7.0 PBS.

Figure S4.

Figure S4. CV responses obtained at GC/Au-bt ESP in 0.1 M PBS (pH 7.0) containing 250.0 µM As(III) (a) and containing 250.0 µM As(III) and 500.0 µM Cu(II) ions (b). Scan rate of 20 mVs-1.

Table S1: Comparison of some analytical characteristics of the present method with other reported methods for As(III) determination.

Electrodea / Techniqueb / Mediumc / Detection Potential (V) / Calibration range (µM) / Detection Limit (µM) / References
PtNTAEs / LSV / 1.0 M H2SO4 / 0.84 / 1-200 / 0.001 / 20
GCE/poly(taurine) nano gold film / CV / pH 7.0, PBS / 0.4 / 6-28 / 0.46 / 23
GCE/CoOx NPs / Amperometry / pH 7.0, PBS / 0.8 / 0.2-100 / 0.011 / 24
GCE/Nf/Fe(dmbpy)32+ / CV / 0.1 M Na2SO4 / 0.78 / 10-100000 / 10 / 25
GCE/Pt NPs / ASV / 1.0 M HClO4 / 0.85 / 1-50 / 0.028 / 27
GCE/polyPN+-Pt NPs / ASV / 0.1 M Na2SO4 / 0.52 / 100-5750 / 2.4 / 28
Pt NPs/SPCEs / CV / 1.0 M H2SO4 / 0.75 / 0.16-1.3 / 0.016 / 29
GCE/Au-CRV / DPV / pH 7.0, PBS / 0.5 / 4-40 / 0.2 / 30
BDD/IrOx / Amperometry / pH 4.3, PBS / 0.6 / 0.02-50 / 0.002 / 31
GCE/bt-Au NPs / CV / pH 7.0, PBS / 0.54 / 1-1700 / 0.1 / Present work

aPtNTAEs = Platinum-nanotube array electrodes, GCE = Glassy carbon electrode, CoOx = Cobalt oxide, NPs = Nanoparticles, Nf/Fe(dmbpy)32+ = Tris(4,4’-dimethyl-2,2’-bipyridine)iron(II)-exchanged Nafion, Pt = Platinum, PN+ = (3-Pyrrol-1-yl propyl)triethylammonium tetrafluoroborate, SPCEs = Carbon-based screen-printed electrodes, Au-CRV = Nano Au-crystal violet, BDD = Boron doped diamond, IrOx = Iridium oxide.

bLSV= Linear scan voltammetry, CV= Cyclic voltammetry, ASV = Anodic stripping voltammetry, DPV = Differential pulse voltammetry

cPBS = Phosphate buffer solution