Polybenzoxazine-Derived N-doped Carbon as Matrix for Powder-Based Electrocatalysts

Abstract

In addition to catalytic activity, intrinsic stability, tight immobilization on a suitable electrode surface, and sufficient electronic conductivity are fundamental prerequisites for the long-term operation of particle- and especially powder-based electrocatalysts. We present a novel approach to concurrently address these challenges by using the unique properties of polybenzoxazine (pBO) polymers, namely near-zero shrinkage and high residual-char yield even after pyrolysis at high temperatures. Pyrolysis of a nanocubic prussian blue analogue precursor (K_m Mn_x [Co(CN)₆ ]_y ⋅n H₂ O) embedded in a bisphenol A and aniline-based pBO led to the formation of a N-doped carbon matrix modified with Mn_x Co_y O_z nanocubes. The obtained electrocatalyst exhibits high efficiency toward the oxygen evolution reaction (OER) and more importantly a stable performance for at least 65 h.

Keywords: catalyst stability; electrocatalysis; oxygen evolution reaction; polybenzoxazine; prussian blue analogue.