Table 2. CV and EIS data produced from the experimental work in Fig. 8 for the synthesized materials modified SPEs^a.

Electrode type	I a (μA)	I c (μA)	E oxd. (V)	E red. (V)	E 1/2 (V)	R s (Ω)	R ct (1) (Ω)	CPE	n μF	W (Ω)	Cs (F g−1)
Bare (unmodified SPE)	19.1	−21.5	0.22	0.093	0.165	102.3	1150	10.5	0.89	178	—
0% W	65.2	−92.3	0.21	0.078	0.144	101.2	450	15.3	0.85	120.3	1114.2
0.5% W	123.6	−149.6	0.25	0.083	0.16	100.1	352.3	16.5	0.78	117.2	1592.8
1.5% W	203.5	−181.3	0.32	−0.016	0.152	50.3	120.6	17.3	0.84	111.6	2178.5
2% W	243.6	−240.9	0.20	0.08	0.14	99.8	90.2	19.8	0.87	95.8	1764.2
2.5% W	86.2	−62.1	0.194	0.068	0.13	100.3	420	15.9	0.89	118.4	828.5

^a I _a: anodic current, I_c: cathodic current, E_oxd: potential of oxidation E_red: potential of reduction, R_s: solution resistance, R_ct: charge transfer resistance, CPE: constant phase element, W: Warburg resistance, C is specific capacitance of the electrodes at scan rate of 50 mV s⁻¹.