An electrochemical and spectroelectrochemical study of pentacoordinated CoTPP on glassy carbon electrode

Electrochemistry as an Attractive and Effective Tool for the Synthesis and Immobilization of Porphyrins on an Electrode Surface

“…Apart from the diazonium electrografting method, the literature mentions a wide range of approaches for the functionalization of surfaces by porphyrins. That includes chemisorption,22 physisorption,23 self‐assembly through tethered functional groups,24 thermolysis,25 click chemistry,26 oxidation of a peripheric terminal alkyne,27 and anodic polymerization 28. Otherwise the surface modification by electrochemical reduction of aryldiazonium salts offers several advantages:7c, 29 a) the ability to control the deposit (e.g., thickness, mono‐ or multilayer character of the film); b) compatibility with a wide range of materials and a great variety of reaction media; c) stability of the organic layer provided by the covalent attachment to the surface; d) ease of preparation of the diazonium salt from the amine precursor; and e) tolerance toward many kinds of functional groups on the aryl backbone.…”

“…Synthesis of nickel(II) 5‐amino‐10,20‐ditolyl‐15‐phenylporphyrin (Ni(PDTPNH 2 )) : The porphyrin Ni(PDTPNH 2 ) was synthesized by metalation of H 2 (PDTPNH 2 ) with Ni(OAc) 2 ⋅4 H 2 O according to known procedures 19c. 22 The porphyrin H 2 (PDTPNH 2 ) (333 mg, 0.573 mmol) was dissolved in DMF (20 mL), and Ni(OAc) 2 ⋅4 H 2 O (717 mg, 2.882 mmol) was added in one portion. The reaction mixture was then degassed with argon for 10 min and heated under reflux conditions in a preheated oil bath (170 °C) for 15 min under argon.…”

Direct Grafting of Free‐Base meso‐Triarylporphyrins on Electrode Materials through Diazonium Reduction: Reversible Zinc(II) Metallation of the Resulting Materials

“…To date, numerous approaches have been developed to deposit the porphyrin moiety on various substrates. These approaches include chemisorption, physisorption, self‐assembly through tethered functional groups, thermolysis, click chemistry, oxidation of terminal alkyne substituents, anodic electropolymerization and covalent attachment through the cathodic electroreduction of diazonium salts . Surface modification via aryl diazonium salts is particular promising since this method allows a fine control of the thickness of the deposited layer (mono‐ and multilayer films) and is compatible with a wide range of substrates.…”

Penta-coordinated transition metal macrocycles as electrocatalysts for the oxygen reduction reaction

“…One of the most interesting non-platinum-based molecular catalysts utilized as electrode materials are phthalocyanines and porphyrins. These structures are macrocycles with metal centers like iron [22][23][24][25][26][27][28], cobalt [29][30][31][32], copper [33][34][35], and nickel [33,34,36] bearing 4 pyrrolic nitrogen atoms. Porphyrins and phthalocyanines have been used as electrodes and have been reported for a wide range of reactions such as the ORR [32,[37][38][39][40], reduction of CO 2 [41][42][43][44][45], and the oxidation of H 2 O 2 and hydrazine [46,47] organic [48][49][50][51][52], biological [53,54] and inorganic compounds [55][56][57][58][59][60][61][62], as well as other forms of bio-mimicking [63,64].…”