LAUSR

Rational exploration of efficient, inexpensive, and robust electrocatalysts is critical for the efficient water splitting. Conjugated conductive metal-organic frameworks (cMOFs) with multicomponent layered double hydroxides (LDHs) to construct bifunctional heterostructure catalysts is considered an efficient but complicated strategy. Here, we report the fabrication of a cMOF/LDH heteronanotree catalyst (CoNiRu-NT) coupled with monodispersed ruthenium (Ru) sites via a controllable grafted-growth strategy. Rich-amino hexaiminotriphenylene (HITP) linkers coordinate with the LDH nanotrunk to form the cMOF nanobranch, providing numerous anchoring sites to precisely confine and stabilize Ru-N4 sites into the CoNiRu-NT heteronanotree structure. Moreover, monodispersed and reduced Ru moieties facilitate H2 O adsorption and dissociation, and the heterointerface between the cMOF and LDH further modifies the chemical and electronic structures. The optimized heteronanotree array CoNiRu-NT displays a significant increase in electrochemical water splitting properties in alkaline media, affording low overpotentials of 22 mV at 10 mA·cm-2 and 255 mV at 20 mA·cm-2 for the hydrogen evolution reaction and oxygen evolution reaction, respectively. In an actual electrochemical system, heteronanotree CoNiRu-NT drives an overall water splitting at a low cell voltage of 1.47 V to reach 10 mA·cm-2 . This performance is comparable to that of pure noble-metal-based materials and superior to that of mostly reported MOF-based catalysts. This article is protected by copyright. All rights reserved.