Synthesis, Characterization and an Electrochemical Study

This study was funded in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brasil (CAPES)—Finance Code 001 and FCT-CAPES project (2019–2020). The authors also thank the funding agencies FAPERJ, CNPq and Fundação para a Ciência e Tecnologia (PEst-C/LA0006/2013, RECI/BBBBQB/0230/2012 as well as “SunStorage—Harvesting and storage of solar energy”, with reference POCI-01-0145-FEDER-016387. The NMR spectrometers are part of the National NMR Network (PTNMR) and are partially supported by Infrastructure Project N° 022161 (co-financed by FEDER through COMPETE 2020, POCI and PORL and FCT through PIDDAC). Ž.P. and H.C. acknowledge Fundação para a Ciência e a Tecnologia, MCTES, for the Norma Transitória DL57/2016 Program contract.Ferrocene-based porous organic polymers (FPOPs) were prepared fromphenol-formaldehyde polymer (Bakelite) and phenol as starting materials; and two possible mechanisms for polymerization were discussed. Solid-state 13C CP-MAS NMR, FTIR, powder XRD, elemental analysis and ICP (Fe, Na, B) were performed to characterize the prepared materials. The two synthetic approaches produced polymers with different pore sizes: the FPOP synthesized through Bakelite presented a higher surface area (52 m2 g1) when compared to the one obtained by the bottom-up polymerization from phenol (only 5 m2 g1). Thermogravimetric analysis confirmed the thermal stability of the material, which decomposed at 350 C. Furthermore, cyclic voltammetry (CV) of the new FPOP on modified electrodes, in ACN and 0.1 M TBAP as an electrolyte, showed fully reversible electron transfer, which is similar to that observed for the ferrocene probe dissolved in the same electrolyte. As a proof-of-concept for an electrochromic device, this novel material was also tested, with a color change detected between yellow/brownish coloration (reduced form) and green/blue coloration (oxidized form). The new hybrid FPOP seems very promising for material science, energy storage and electrochromic applications, as well as for plastic degradation.publishersversionpublishe