Robust and conductive Magnéli Phase Ti<inf>4</inf>O<inf>7</inf> decorated on 3D-nanoflower NiRu-LDH as high-performance oxygen reduction electrocatalyst

Abstract

Escalating both electrochemically active and stable materials at a time is an important challenge in the field of catalysis till to date. Carbon as a pillar material has been used for long time due to its intrinsic properties like high conductivity and large surface area that can increase activity of electrocatalyst. However, severe drop in activity due to carbon corrosion is the main challenge. Here, we introduce robust, conductive and stable Magnéli phase Ti4O7 nano-pillar in to flower like nickel ruthenium-layered double hydroxide (3D-FL-NiRu-LDH/ Ti4O7) through an easy in situ growth approach for the first time. The decoration of Magnéli phase Ti4O7 not only significantly improves the activity but also stability of LDH nanosheet catalyst. The as-synthesized materials retain 98% of the activity after 45 h which surpasses all the reported LDH catalysts for oxygen reduction reaction under alkaline media. The key roles of Ti4O7 are to provide the effective charge transfer networks of LDH catalyst and prevent agglomeration of LDH catalysts though strongly coupled interactions evidenced by X-ray photoelectron spectroscopy (XPS). Therefore, the developed catalyst demonstrates promising conductivity, together with durability. The reported approach of introducing a robust and conductive pillar coupled with LDH catalysts provides a novel pathway for developing a highly efficient and durable electrocatalyst.