Hydrogen Gas Generation Using Self-Assembled Monolayers (SAMs) of 5,10,15,20-Tetrakis (p-Thiophenol) Porphyrin on a Gold Electrode
Open Access
Abstract
A novel approach was used to synthesize the 5,10,15,20-tetrakis (p-thiophenol) porphyrin (TPTH-P) (2), which involved the demethylation of tetra (p-anisole) porphyrin (1) in the presence of ZnCl2 as a catalyst and DMF as a solvent at 100 °C. The demethylation step was followed by an acidification step with concentrated H2SO4 to yield the desired TPTH-P (2) in an almost quantitative yield (95%). The chemical structure of the synthesized porphyrin thiol (TPTH-P) (2) was verified through spectroscopic techniques (NMR, IR, UV-Vis). The catalytic activity of TPTH-P in the hydrogen evolution reaction (HER) was investigated in 0.1 M of H2SO4 and 1 M of KNO3. A self-assembled monolayer (SAM) of TPTH-P was formed on a gold electrode. The immersion time during SAM formation and the electrochemical activation cycles in H2SO4 were found to be important to enhancing the activity of the Au-TPTH-P electrode in the HER. Contact angle measurements and electrochemical techniques, including cyclic voltammetry (CV), linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS), and chronoamperometry, were used to characterize and evaluate the electrochemical activities of the SAM.Keywords
Funding Information
- Dean of Scientific Research at King Faisal University (4210)
This publication has 27 references indexed in Scilit:
- Defect‐Rich MoS2 Ultrathin Nanosheets with Additional Active Edge Sites for Enhanced Electrocatalytic Hydrogen EvolutionAdvanced Materials, 2013
- Self-Assembled Mono layers of Disulfide Cu Porphyrins on Au Surfaces: Adsorption Induced Reduction and DemetalationLangmuir, 2011
- Detection of Hydrogen Peroxide Produced during the Oxygen Reduction Reaction at Self-Assembled Thiol−Porphyrin Monolayers on Gold using SECM and NanoelectrodesLangmuir, 2010
- Electrochemical Characterization of Self‐Assembled Thiol‐Porphyrin Monolayers on Gold Electrodes by SECMChemphyschem, 2006
- Electron Transport through a Self-Assembled Monolayer of Thiol-End-Functionalized Tetraphenylporphines and Metal TetraphenylporphinesLangmuir, 2006
- Size‐Controlled Electrochemical Synthesis of Metal Nanoparticles on Monomolecular TemplatesAngewandte Chemie International Edition, 2005
- Self-Assembled Monolayers of Thiolates on Metals as a Form of NanotechnologyChemical Reviews, 2005
- Self‐Assembled Monolayers into the 21st Century: Recent Advances and ApplicationsElectroanalysis, 2003
- Preparation and Characterization of a Porphyrin Self-Assembled Monolayer with a Controlled Orientation on GoldLangmuir, 1999
- Electrochemical Post-Self-Assembly Transformation of 4-Aminothiophenol Monolayers on Gold ElectrodesLangmuir, 1998