Tuning Complex Transition Metal Hydroxide Nanostructures as Active Catalysts for Water Oxidation by a Laser–Chemical Route

Abstract

Diverse transition metal hydroxide nanostructures were synthesized by laser-induced hydrolysis in a liquid precursor solution for alkaline oxygen evolution reaction (OER). Several active OER catalysts with fine control of composition, structure, and valence state were obtained including (Li x )­[Ni0.66Mn0.34(OH)2]­(NO3)­(CO3) · mH2O, Li x [Ni0.67Co0.33(OH)2]­(NO3)0.25(ORO)0.35 · mH2O, etc. An operate overpotential less than 0.34 V at current density of 10 mA cm–2 was achieved. Such a controllable laser–chemical route for assessing complex nanostructures in liquids opens many opportunities to design novel functional materials for advanced applications.

A spongy nickel-organic CO 2 reduction photocatalyst for nearly 100% selective CO production

“…For the spongy Ni(TPA/TEG) catalyst, it is likely that the Ni-TPA coordination units are unfavorable for the binding of H · on the active sites, limiting the proton transfer and the formation of H 2 . In addition, the flexible Ni-TEG units, with superior structural resistance to the aqueous environment ( 23 ), enable the disordered spongy network construction, where the open and defective structure provides more accessible Ni 2+ active sites to capture and stabilize the CO 2 · − intermediates, leading to the efficient production of CO.…”

“…Specifically, we used an unfocused infrared laser to initiate the reactions between transition metal ions and triethylene glycol (TEG) and obtained a series of metal hydroxide–TEG composites with a distorted layered structure ( 23 ). This disordered structure enhances the accessibility of water molecules to the active sites and enables efficient electrocatalysis of alkaline water oxidation ( 23 ). Such a laser-chemical strategy may be applied to the discovery of many other catalysts, for instance, novel nanostructured metal-organic heterogeneous catalysts for CO 2 reduction reaction.…”

Recent Progress on Multimetal Oxide Catalysts for the Oxygen Evolution Reaction

“…[27,64,[78][79][80][81][82][83][84][85] In particular, 3d transition metals such as Zn, Mn, Fe, and Ni have been mixed with Co for the improvement of the catalytic activity. Zou et al reported Zn-Co LDH prepared by a simple coprecipitation method as an efficient water and alcohol oxidation catalyst.…”

“…Niu et al reported a laser-induced hydrolysis method that allows precise control of the composition, structure, and valence state. [81] Using this method, they synthesized various OER hydroxide catalysts using Li, Ni, Co, and Mn with finely controlled composition, structure, and valence state of the metal. According to solvent control analysis, the valence state of the metal and crystallinity were found to be affected by the type of solvent (e.g., water, triethylene glycol, or ethylene glycol).…”

Ultrathin Two‐Dimensional Nanostructured Materials for Highly Efficient Water Oxidation

“…The two different types have a similar host layer consisting of brucite‐like metal‐hydroxyl building units without any intercalated species or with neutral molecules and negatively charged anions in the interlayer with weak interaction. Single metal hydroxides and LDHs with transition‐metal elements have been widely studied as one of the most promising OER catalysts due to the presence of active MO 6 octahedra …”