The performance of the different modified electrodes for the detection of NO2–
| Electrode materials | Medium | Potential (V) | LR (µM) | LOD (µM) | Ref. | 
|---|---|---|---|---|---|
| Ag-HNT MoS2/GCE | 0.1 M PBS (pH = 4) | 0.8 V (Ag/AgCl) | 2–425 | 0.7 | [9] | 
| PEDOT-AuNPs/GCE | 0.1 M PBS (pH = 5) | 0.78 V (SCE) | 3–300 | 0.1 | [10] | 
| rGO-MoS2/GCE | 0.1 M PBS (pH = 7) | 0.8 V (Ag/AgCl) | 0.2–4,800 | 0.17 | [11] | 
| Cu/Ag/MWCNTs/GCE | 0.1 M PBS (pH = 7) | 0.85 V (SCE) | 1–1,000 | 0.2 | [12] | 
| nHAP-PEDOT/GCE | 0.2 M PBS (pH = 8) | 0.78 V (SCE) | 0.25–1.05 | 0.083 | [30] | 
| Fe2O3-MoS2/GCE | 0.1 M PBS (pH = 4) | 1.0 V (SCE) | 2–6,730 | 1.0 | [31] | 
| CG-Ppy-CS/GCE | 0.1 M AcHAC (pH = 4) | 0.87 V (Ag/AgCl) | 0.2–1,000 | 0.02 | [32] | 
| Poly (4-AB/OT)/CPE | 0.1 M PBS (pH = 5) | 0.95 V (Ag/AgCl) | 6–600 | 3.5 | [33] | 
| a-Fe2O3/CNTs/GC | 0.1 M PBS (pH = 7) | 0.95 V (Ag/AgCl) | 0.5–4,000 | 0.15 | [39] | 
| MWCNTs/Pt | 0.1 M PBS (pH = 7) | 0.70 V (SCE) | 1–1,000 | 0.1 | This work | 
GCE: glassy carbon electrode; PBS: phosphate-buffered solution; CPE: carbon-paste electrode; AuNPs: gold nanoparticles; SCE: saturated calomel electrode; Poly (4-AB/OT): poly(4-aminobenzoic acid/o-toluidine); Ppy: polypyrrole; CG: carboxyl graphene; nHAP: nanosized hydroxyapatite; MWCNTs: multi-walled carbon nanotubes; LR: linear range; LOD: limit of detection; HNT: halloysite nanotube; GC: galssy carbon; PEDOT: poly(3,4-ethylenedioxythiophene); rGO: reduced graphene oxide; CNTs: carbon nanotubes; CS: chitosan; AcHAC: acetic acid-sodium acetate