Photoreductive Electron Transfers in Nanoarchitectonics Organization Between a Diketopyrrolopyroleplatinum(II)-Containing Organometallic Polymer and Various Electron Acceptors

A platinum(II) polyyne/diketopyrrolopyrole-containing polymer of two different chain lengths, P (short) and P’ (long chain), were prepared in order to elucidate the reasons for the poor photoconversion efficiencies (PCEs) in bulk heterojunction solar cells recently reported in the Journal of Organometallic Chemistry (2019), 894, 1–9, whereas other solar cells using similar platinum(II) polyyne/diketopyrrolopyrole-containing polymers provided significantly better PCEs. Using thermodynamic arguments using electrochemical and spectroscopy data, quenching experiments of the fluorescence band of P using fullerene (PC 61 BM and PC 71 BM) nonfullerene (MCzM) acceptors, and testing photochemical stability of P and P’, three possible reasons were found. These reasons are the undetected photochemical instability of similar polymers used by Wong, and the likely inappropriate choice of electron acceptor (PC 61 BM) in this past investigation. Graphical Abstract