title: Cadmium Sulphide-Reduced Graphene Oxide-Modified Photoelectrode-Based Photoelectrochemical Sensing Platform for Copper(II) Ions.
abstract: A photoelectrochemical (PEC) sensor with excellent sensitivity and detection toward copper (II) ions (Cu2+) was developed using a cadmium sulphide-reduced graphene oxide (CdS-rGO) nanocomposite on an indium tin oxide (ITO) surface, with triethanolamine (TEA) used as the sacrificial electron donor. The CdS nanoparticles were initially synthesized via the aerosol-assisted chemical vapor deposition (AACVD) method using cadmium acetate and thiourea as the precursors to Cd2+ and S2-, respectively. Graphene oxide (GO) was then dip-coated onto the CdS electrode and sintered under an argon gas flow (50 mL/min) for the reduction process. The nanostructured CdS was adhered securely to the ITO by a continuous network of rGO that also acted as an avenue to intensify the transfer of electrons from the conduction band of CdS. The photoelectrochemical results indicated that the ITO/CdS-rGO photoelectrode could facilitate broad UV-visible light absorption, which would lead to a higher and steady-state photocurrent response in the presence of TEA in 0.1 M KCl. The photocurrent decreased with an increase in the concentration of Cu2+ ions. The photoelectrode response for Cu2+ ion detection had a linear range of 0.5-120 μM, with a limit of detection (LoD) of 16 nM. The proposed PEC sensor displayed ultra-sensitivity and good selectivity toward Cu2+ ion detection.
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
authors.forename: I
authors.initials: I
authors.lastname: Ibrahim
authors.affiliation: Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.|Functional Device Laboratory, Institute of Advanced Technology, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia.
authors.forename: H N
authors.initials: HN
authors.lastname: Lim
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia.
authors.forename: N M
authors.initials: NM
authors.lastname: Huang
authors.affiliation: Low Dimensional Materials Research Centre, Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, 50603, Malaysia.
authors.forename: A
authors.initials: A
authors.lastname: Pandikumar
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D003300:Copper / Q000032:analysis*; D058266:Dielectric Spectroscopy; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006108:Graphite / Q000737:chemistry*; D007477:Ions; D008027:Light; D053761:Nanocomposites / Q000648:ultrastructure; D054118:Nanospheres / Q000648:ultrastructure; D010084:Oxidation-Reduction; D013059:Spectrum Analysis, Raman; D013440:Sulfides / Q000737:chemistry*; D017971:Tin Compounds / Q000737:chemistry; D014961:X-Ray Diffraction
chemical_list: D019187:Cadmium Compounds; D007477:Ions; D013440:Sulfides; D017971:Tin Compounds; C034939:cadmium sulfide; C109984:indium tin oxide; D006108:Graphite; D003300:Copper