CO2 to CO Electroreduction, Electrocatalytic H2 Evolution, and Catalytic Degradation of Organic Dyes Using a Co(II) meso-Tetraarylporphyrin

Abstract

The meso-tetrakis(4-(trifluoromethyl)phenyl)porphyrinato cobalt(II) complex [Co(TMFPP)] was synthesised in 93% yield. The compound was studied by 1H NMR, UV-visible absorption, and photoluminescence spectroscopy. The optical band gap Eg was calculated to 2.15 eV using the Tauc plot method and a semiconducting character is suggested. Cyclic voltammetry showed two fully reversible reduction waves at E1/2 = −0.91 V and E1/2 = −2.05 V vs. SCE and reversible oxidations at 0.30 V and 0.98 V representing both metal-centred (Co(0)/Co(I)/Co(II)/Co(III)) and porphyrin-centred (Por2−/Por−) processes. [Co(TMFPP)] is a very active catalyst for the electrochemical formation of H2 from DMF/acetic acid, with a Faradaic Efficiency (FE) of 85%, and also catalysed the reduction of CO2 to CO with a FE of 90%. Moreover, the two triarylmethane dyes crystal violet and malachite green were decomposed using H2O2 and [Co(TMFPP)] as catalyst with an efficiency of more than 85% in one batch.

Antibacterial Activity of Solvothermal Obtained ZnO Nanoparticles with Different Morphology and Photocatalytic Activity against a Dye Mixture: Methylene Blue, Rhodamine B and Methyl Orange

“…The textile industry is such an example, where ZnO NPs are employed as an antimicrobial agent and as a UV-shield, being embedded in the fibrillary structure [ 61 ]. If ZnO NPs exhibit high photocatalytic activity in this case, they would degrade the organic support that they are meant to protect [ 62 , 63 , 64 ]. Therefore, such behavior is not desirable.…”

Influence of the Alcohols on the ZnO Synthesis and Its Properties: The Photocatalytic and Antimicrobial Activities

“…For example, in the textile industry, ZnO nanoparticles can be used as a UV shield and as an antimicrobial agent when they are embedded in the fibrillary structure [120][121][122][123]. A photocatalytic activity in this case is not desirable, as the ZnO nanoparticles would degrade the organic support that they are meant to protect [124][125][126]. The calculated parameters for each dye used are presented in Table 6.…”

[W10O32]4−-based POMOFs with different nuclear cobalt clusters for photoreduction of CO2 to produce syngas

“…S4b, ESI †), which were generally considered to be Co II /Co I . [68][69][70] The LUMO of compounds 1 and 2 were mainly distributed on cobalt ions, and was analysed used DFT calculations. The process of electron transfer may be that the excited photoelectrons from [Ru(bpy) 3 ]Cl 2 transferred to the Co site by the internal transfer of the catalyst, and further reduced the Co 2+ to Co + .…”