Lattice Matching Growth of Conductive Hierarchical Porous MOF/LDH Heteronanotube Arrays for Highly Efficient Water Oxidation

Abstract

The conjugation of metal–organic frameworks (MOFs) into different multicomponent materials to precisely construct aligned heterostructures is fascinating but elusive owing to the disparate interfacial energy and nucleation kinetics. Herein, a promising lattice‐matching growth strategy is demonstrated for conductive MOF/layered double hydroxide (cMOF/LDH) heteronanotube arrays with highly ordered hierarchical porous structures enabling an ultraefficient oxygen evolution reaction (OER). CoNiFe‐LDH nanowires are used as interior template to engineer an interface by inlaying cMOF and matching two crystal lattice systems, thus conducting a graft growth of cMOF/LDH heterostructures along the LDH nanowire. A class of hierarchical porous cMOF/LDH heteronanotube arrays is produced through continuously regulating the transformation degree. The synergistic effects of the cMOF and LDH components significantly promote the chemical and electronic structures of the heteronanotube arrays and their electroactive surface area. Optimized heteronanotube arrays exhibit extraordinary OER activity with ultralow overpotentials of 216 and 227 mV to deliver current densities of 50 and 100 mA cm−2 with a small Tafel slope of 34.1 mV dec−1, ranking it among the best MOF and non‐noble‐metal‐based catalysts for OER. The robust performance under high current density and vigorous gas bubble conditions enable such hierarchical MOF/LDH heteronanotube arrays as promising materials for practical water electrolysis.

Competitive Coordination‐Oriented Monodispersed Ruthenium Sites in Conductive MOF/LDH Hetero‐Nanotree Catalysts for Efficient Overall Water Splitting in Alkaline Media

“…[ 13 ] In our previous study, a unique heterostructure nanotube, which was constructed via the close lattice match between cMOF and the inorganic substrate along with three directions ( a , b , and c axis), exhibited the improved performance. [ 14 ] Even so, few attempts were performed on the construction of cMOF‐based heterostructures with monodispersed metals sites via bridging the functional organic linkers. As for the cMOF family, the hexatopic triphenylene organic ligands (OH, SH, NH 2 ), especially the deprotonated NH 2 can act as a Lewis base and a redox units to construct functionalized cMOF‐assisted heterostructure electrocatalyst materials.…”

Sub‐2 nm Ultrathin and Robust 2D FeNi Layered Double Hydroxide Nanosheets Packed with 1D FeNi‐MOFs for Enhanced Oxygen Evolution Electrocatalysis

“…[13] In addition, hybridizing LDHs with MOF structures is also a promising way to enhance electrocatalytic activity. [14] Notably, LDHs have adjustable and reasonable layer spacing, which allows organic ligands to coordinate with interlayer metal ions, thus making them a promising precursor to form MOFs. [11c,15] It should be pointed out that these reported works mainly focused on the complete transformation of 2D LDH to MOF nanosheets, or partial transformation to core-shell stuctures.…”

Corrosive-coordinate engineering to construct 2D-3D nanostructure with trace Pt as efficient bifunctional electrocatalyst for overall water splitting

“…On the basis of the above merits, hybridization of 2D metal hydroxides and 3D MOF into an integrated morphology will deliver remarkable electrocatalytic performances. For instance, Zhai and co-authors [39] constructed conductive MOF/layered double hydroxide (LDH) heteronanotube arrays by a solvothermal procedure followed by heat treatment; the arrays presented an extraordinary OER performance in the alkaline electrolyte at 216 mV to deliver 50 mA cm −2 photocurrent density. In general, metal hydroxides are prepared via a high-temperature solvothermal process under high pressure [40].…”