Contributed Talk  - Thursday, 16 September I 14:20 PM (CEST)

Gianlorenzo Bussetti: "Porphyrin films for in-operando HOPG protection"

G. Bussetti¹,*, M. Penconi², R. Yivlialin³, ‡, L. Duo¹, A. Bossi², A. Orbelli Biroli².

 

¹ Department of Physics, Politecnico di Milano, piazza Leonardo da Vinci 32, 20133 Milano, Italy.

² Istituto di Scienze e Tecnologie Chimiche "G. Natta" del CNR (CNR-SCITEC) and SmartMatLab Centre, Italy

‡ current address: Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin, Germany

 

* e-mail: gianlorenzo.bussetti@polimi.it

The ultimate goal of surface protection by organic thin films is the fine control of the molecular arrangement of properly designed materials. The organic film properties are even more critical when the protection ability must not perturb the underneath active surface function as in the case of in operando electrodes covered by suitable materials. In this talk, we prove that a vacuum deposited thin film of meso-tetraphenylporphyrin (H2TPP) on a highly-oriented pyrolytic graphite (HOPG) electrode can screen the electrode against anion intercalation. In addition, we are able of tuning this effect by tailoring the peripheral groups of the porphyrin skeleton. Electrochemical atomic force microscopy (EC-AFM) and cyclic voltammetry (CV) investigations highlight the important role played by the molecular/electronic structure of the porphyrins to enhance both the molecule-substrate interaction and the molecular assembly. In particular, perfluorinated TPP show the better protection ability in acid environment.

 

 

Biography:

M. Penconi, R. Yivlialin, G. Bussetti, L. Duò, et al., Customised porphyrin coating films for graphite electrode protection: an investigation on the role of peripheral groups by coupled AFM and cyclic voltammetry techniques. Appl. Surf. Sci. 507 (2020) 145055

R. Yivlialin, M. Penconi, G. Bussetti, A. Orbelli Biroli, et al., Morphological changes of porphine films on graphite by perchloric and phosphoric electrolytes: an electrochemical-AFM study. Appl. Surf. Sci. 442 (2018) 501.

R. Yivlialin, L. Magagnin, L. Duò, G. Bussetti, Blister evolution time invariance at very low electrolyte pH: H₂SO₄/graphite system investigated by electrochemical atomic force microscopy. Electrochimica Acta 276 (2018) 352.