The electrochemical behavior of p-benzenediol on a self-assembled monolayers Pt electrode modified with N-(2-mercapto-1,3,4-thiadiazol-5-yl)-N'-(4-substituted-arylacetyl) urea.
Two novel N-(2-mercapto-1,3,4-thiadiazol-5-yl)-N'-(4-substituted-arylacetyl) urea compounds have been synthesized, characterized by NMR and MS, and used as self-assembly reagents to form self-assembled monolayers (SAMs) on Pt electrodes. The modified electrodes were characterized by electrochemical methods. The electrochemical behavior of p-benzenediol at the SAMs electrodes was investigated. It was found that the electrochemical response to p-benzenediol is controlled by diffusion and can be electrocatalyzed to obtain more symmetrical redox peaks and higher voltammetric current response at the SAMs electrodes, with a peak separation of 80 mV. For p-benzenediol the process at the SAMs electrodes is quasi-reversible with a rate constant of 0.6742 s-1. The SAMs electrodes have been used to determine p-benzenediol by differential pulse voltammetry. The peak current was linear for concentrations of p-benzenediol in the range 1x10(-7)-5x10(-4) mol L-1 and the detection limit was 4.0x10(-8) mol L-1. The SAMs electrodes were used to determine p-benzenediol in real photographic developer and in a synthetic waste water sample; the standard addition recovery was in the range 96.6-100.4%.
Liu
Chuan-yin
CY
Department of Chemistry, Yunyang Teachers College, Danjiangkou, 442700, People's Republic of China.
Yao
Ji-ping
JP
Tang
Hong-wu
HW
Zhu
Sheng-ping
SP
Hu
Jun-fu
JF
D004563:Electrochemistry; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D006873:Hydroquinones / Q000737:chemistry*; D015394:Molecular Structure; D010984:Platinum / Q000737:chemistry*; D015203:Reproducibility of Results; D012996:Solutions; D013830:Thiadiazoles / Q000737:chemistry*; D014508:Urea / Q000031:analogs & derivatives* / Q000737:chemistry
D006873:Hydroquinones; D012996:Solutions; D013830:Thiadiazoles; D010984:Platinum; D014508:Urea; C031927:hydroquinone