scholarly journals Inside Cover: Bipolar Electrochemical Approach with a Thin Layer of Supporting Electrolyte towards the Growth of Self-Organizing TiO2Nanotubes (ChemElectroChem 3/2016)

2016 ◽  
Vol 3 (3) ◽  
pp. 349-349 ◽  
Author(s):  
Muhammad Saqib ◽  
Jianping Lai ◽  
Jianming Zhao ◽  
Suping Li ◽  
Guobao Xu
2015 ◽  
Vol 3 (3) ◽  
pp. 360-365 ◽  
Author(s):  
Muhammad Saqib ◽  
Jianping Lai ◽  
Jianming Zhao ◽  
Suping Li ◽  
Guobao Xu

2016 ◽  
Vol 3 (3) ◽  
pp. 350-350
Author(s):  
Muhammad Saqib ◽  
Jianping Lai ◽  
Jianming Zhao ◽  
Suping Li ◽  
Guobao Xu

2012 ◽  
Vol 16 (05n06) ◽  
pp. 674-684 ◽  
Author(s):  
Zhongping Ou ◽  
Weihua Zhu ◽  
Paul J. Sintic ◽  
Yuanyuan Fang ◽  
Maxwell J. Crossley ◽  
...  

Electrochemical and thin-layer spectroelectrochemical properties of mono- and bis-porphyrins containing a β,β′-fused tetraazaanthracene (TA) group were examined in CH2Cl2 , PhCN and pyridine containing 0.1 M tetra-n-butylammonium perchlorate as supporting electrolyte. The investigated mono-porphyrins are represented as (PTA)M, where M = 2H, Cu(II) or Zn(II) and PTA = the dianion of 5,10,15,20-tetrakis-(3,5-di-tert-butylphenyl)-6′,7′-dimethyl-1′,4′,5′,8′-tetraazaanthraceno-[2′,3′b]-porphyrin, while the bis-porphyrins are represented by M(P)-TA-(P)M, where M is H2 , Cu(II) , Zn(II) , Ni(II) or Pd(II) and P is the dianion of 5,10,15,20-tetrakis-(3,5-di-tert-butylphenyl)porphyrin. The effect of the fused TA group on the redox potentials and UV-visible spectra of the neutral, electroreduced and electrooxidized porphyrins is discussed and the data compared to what is observed for related mono- and bis-quinoxalinoporphyrins of the type (PQ)M and (QPQ)M, where Q is a β,β′-fused quinoxaline group. Each TA-linked bis-porphyrin exhibits a strong interaction between the two equivalent porphyrin macrocycles, the magnitude of which is dependent upon the specific metal ion.


2015 ◽  
Vol 19 (01-03) ◽  
pp. 388-397 ◽  
Author(s):  
Yuanyuan Fang ◽  
Federica Mandoj ◽  
Lihan Zeng ◽  
Rajesh Pudi ◽  
Manuela Stefanelli ◽  
...  

Bis-porphyrins containing a β,β′-fused pyrazino (Pz) linking group were examined by electrochemistry and thin-layer UV-visible spectroelectrochemistry in PhCN containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) as supporting electrolyte. The investigated compounds are represented as M(TPP)-Pz-(TPP)M, where TPP is the dianion of tetraphenylporphyrin and M = Zn(II) , Cu(II) or Ag(II) . The effect of the linking Pz group on the redox potentials and UV-visible spectra of the neutral, electroreduced and electrooxidized bis-porphyrins is discussed and the data compared to what is observed for related monoporphyrins and earlier characterized bis-porphyrins containing a tetraazaanthracene (TA) linking group and the same central metal ions. The Cu(II) and Zn(II) Pz linked bis-porphyrins exhibit a relatively strong interaction between the two equivalent porphyrin macrocycles as evidenced by UV-visible spectra of the neutral compounds and characteristic splitting of redox processes for three of the four electron transfer reactions, the one exception being the first oxidation, where no splitting of potentials is observed in the formation of the bisporphyrin bis-cation radical, [M(TPP)-Pz-(TPP)M]2+. The first oxidation and first reduction of the bis-porphyrin with two Ag(II) central metal ions occurs via two overlapping one-electron transfer steps in each process indicating equivalent, but non-interacting redox centers. This difference in redox behavior is due to differences in the site of electron transfer, metal centered for the Ag(II) bisporphyrins, which undergo Ag(II) / Ag(III) and Ag(II) / Ag(I) processes as compared to only ring centered electron transfers for the Cu(II) and Zn(II) derivatives. The Pz-linked Zn(II) bis-porphyrins have a larger average HOMO–LUMO gap (2.01 V) as compared to related tetraazaanthracene linked bis-porphyrins (1.67 V), which were earlier characterized in the literature, but the gap is smaller than that for the mono-porphyrins with the same central metal ions (2.17 V). Each redox reaction of the investigated bisporphyrins was characterized by thin-layer spectroelectrochemistry.


2019 ◽  
Vol 10 (1) ◽  
pp. 11-19
Author(s):  
Milivoj Lovrić

A model of reversible and quasi-reversible electrode reaction of dissolved redox couple is developed for the staircase voltammetry and the twin electrode thin layer cell. It is assumed that the neutral molecule is oxidized to a monovalent cation. The calculations were performed for the absence of supporting electrolyte and for its various concentrations. The influence of migration of cations and of IRΩ drop on the peak currents and peak potentials was investigated. Also, the kinetically controlled electrode reactions were simulated. These reactions can be distinguished from the reactions influenced by the resistance in the solution.


Sign in / Sign up

Export Citation Format

Share Document