Electronic Supplementary Information (ESI) Three dimensional dendrite Cu-Co/rGO architectures on disposable pencil graphite electrode as an electrochemical sensor for non-enzymatic glucose detection K. Justice Babu, Sunirmal Sheet, Yang Soo Lee, and G. Gnana kumar*, Department of Physical Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai-625021, Tamil Nadu, India Department of Forest Science and Technology, College of Agriculture and Life Sciences, Chonbuk National University, 567Baekje-daero, Jeonju-si, Jeollabuk-do, Republic of Korea * Corresponding author: G. Gnana kumar : e-mail: kumarg2006@gmail.com; Tel.No:91-9585752997 50 µm (a) Figure S1. SEM image of PGE. 50 µm S1
Figure S2. EDAX patterns of (a) PGE, (b) Cu/PGE, (c) Cu-Co/PGE, and Cu-Co/rGO/PGE. S2
Figure S3. XPS core level spectra of (i) Cu 2p, (ii) Co 2p and (iii) C 1s energy levels of Cu-Co/rGO. S3
Figure S4. CV of Cu/PGE in 0.1 M NaOH at a scan rate of 20 mv s -1 (insets (a) and (b) show the corresponding magnified CV curve). S4
Figure S5. Plot of Ipa vs. pencil grade obtained from the Cu-Co/rGO nanostructures deposited over the different pencil grades in the presence of 5 mm glucose in 0.1 M NaOH at a scan rate of 20 mv s -1. S5
Figure S6. Calibration plot of (a) Ip vs. v 1/2 and (b) log Ip vs. log v for the CVs obtained at Cu-Co/rGO/PGE in the presence of 5 mm glucose as a function of scan rates in 0.1 M NaOH solution. S6
Figure S7. Electrochemical impedance spectra of studied PGEs in 0.1 M NaOH solution containing 5 mm glucose at the frequency range of 0.1HZ 0.1 MHZ. S7
Figure S8. The stability profile of Cu-Co/rGO/PGE in 2 mm glucose in 0.1 M NaOH solution. 50 µm S8
Table S1. Comparison of the electrochemical performances of enzyme-free glucose sensors. Electrode materials Linear range (mm) LOD a (μm) Sensitivity (μamm -1 cm -2 ) Ref. Co 3 O 4 /PbO 2 /carbon cloth 0.005-1.2 5 460.3 1 NiCo 2 O 4 /ITO b 0.005-0.065 0.38 6.69 r 2 rgo c /Cu NPs/Au 0.01-1.2 3.4 447.65 3 NiCo 2 S 4 /Pt 0.001-0.664 1.2 5.14 r 4 CuOx-CoOx/rGO c /GCE d 0.005-0.57 0.5 507 5 Graphene/Cu/GCE d up to 4.5 0.5-6 Cu NPs e /ZnO/ITO b 0.001-1.53 0.2 0.16 q 7 Ni-Co NSs/RGO c /GCE d 0.01 2.65 3.79 1773.61 8 Cu-NG f /GCE d 0.004 4.5 1.3 48.13 q 9 CuNi/KTO g /ITO b 0.001-0.5 0.35 661.5 q 10 Ti/TiO 2 NTA h /Ni 0.1-1.7 4 200 11 Cu CuO/C i Upto 3 5 598 12 NiCFP j electrode 0.002-2.5 1 420.4 13 PVdF-HFP k /Ni/Co 0.001 7.0 0.26 7.56 14 NiNPs/TiO 2 Ny NWAs l 0.001 1 0.39 421 15 CoOOH NSA m /Ti foils 0.003-1.109 1.37 526.8 16 Cu/CuO/ZnO 0.1-1.0 18 408 17 CuNiO-GR n /GCE d 0.05-6.9 16 200 18 PtNi/ERGO o /GCE d Upto 35 10 20 19 Cu-Co/rGO c /PGE p 0.001-4 0.15 240 This work a limit of detection, b indium tin oxide, c reduced graphene oxide, d glassy carbon electrode, e nanoparticles, f nitrogen-doped graphene, g layered lithium potassium titanate, h nanotube arrays, i carbon electrode, j carbon nanofiber paste electrode, k polyvinylidenefluoride-cohexafluoropropylene, l nitrogen-doped TiO 2 nanowire arrays, m nanosheet arrays, n graphene, o electrochemically reduced graphene oxide, p pencil graphite electrode, q µamm -1, r μaμm -1 cm -2. S9
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