Exciting lattice oxygen of nickel–iron bi-metal alkoxide for efficient electrochemical oxygen evolution reaction

High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage systems.The electro-oxidation of water to oxygen plays a crucial role in such energy conversion technologies.Herein,we report a robust method for the synthesis of a bimetallic alkoxide for efficient oxygen evolution reaction(OER)for alkaline electrolysis,which yields current density of 10 mA cm^(-2)at an overpotential of 215 mV in 0.1 M KOH electrolyte.The catalyst demonstrates an excellent durability for more than 540 h operation with negligible degradation in activity.Raman spectra revealed that the catalyst underwent structure reconstruction during OER,evolving into oxyhydroxide,which was the active site proceeding OER in alkaline electrolyte.In-situ synchrotron X-ray absorption experiment combined with density functional theory calculation suggests a lattice oxygen involved electrocatalytic reaction mechanism for the in-situ generated nickel–iron bimetal-oxyhydroxide catalyst.This mechanism together with the synergy between nickel and iron are responsible for the enhanced catalytic activity and durability.These findings provide promising strategies for the rational design of nonnoble metal OER catalysts.

Interfacial synergism of hollow mesoporous Pt/WO_(x)/SiO_(2)-TiO_(2)catalysts enable highly selective hydrogenolysis of glycerol to 1,3-propanediol

The selective hydrogenolysis of glycerol exhibits great prospects,while the catalysts with high selectivity and activity are still missing and need to be created urgently.Herein,we report the synthesis of hollow mesoporous Pt/WO_(x)/SiO_(2)-TiO_(2)nanosphere catalysts with bi-functional interfaces synergistically for high efficiency conversion of glycerol to 1,3-propanediol.The hollow mesoporous Pt/WO_(x)/SiO_(2)-TiO_(2)catalysts show a typical brick-concrete liked framework with a high surface area(179.3 m^(2)·g^(-1)),large mesopore size(10.6 nm),uniform particle size(~400 nm),and ultrathin shell thickness(~75 nm).The brick anatase nanocrystals and concrete amorphous SiO_(2)networks can selectively rivet Pt nanoparticles and WO_(x)nanocluster species,respectively,thus constructing two interfaces for effective adsorption,rapidly catalytic dehydration and hydrogenation processes.The hollow mesoporous Pt/WO_(x)/SiO_(2)-TiO_(2)catalysts deliver a high selectivity of 53.8%for 1,3-propanediol(1,3-PDO)at a very high glycerol conversion of 85.0%.As a result,a favorable 1,3-PDO yield of 45.7%can be obtained with excellent stability,which is among the best performances of previously reported catalysts.This work paves a new way to synthesize catalysts with high selectivity,high activity and high stability.

Borates as a new direction in the design of oxide ion conductors

Lowering the operating temperature of solid oxide fuel cells(SOFCs)has extensively stimulated the development of new oxide ion conductors.Here,inspired by the structural commonalities of oxide ion conductors,the inability to accommodate oxygen vacancies in the rigid,isolated,3-fold tetrahedral rings of SrSi/GeO_(3)-based materials,and the considerable flexibility of BO_(n) polyhedra in terms of coordination number,rotation,deformation,and linkage,we report the first borate-base family of oxide ion conductors,(Gd/Y)_(1−x)Zn_(x)BO_(3−0.5x),through combined computational prediction and experimental verification.The oxygen vacancies in(Gd/Y)BO_(3)can be accommodated by forming B_(3)O_(8)units in isolated,3-fold,tetrahedral rings of B_(3)O_(9)and transported through a cooperative mechanism of oxygen exchange between the B_(3)O_(9)and B_(3)O_(8)units,which is assisted by the intermediate opening and extending of these units.This study opens a new scientific field of the borate system for designing and discovering oxide ion conductors.

Erratum to:Borates as a new direction in the design of oxide ion conductors(vol 65,issue 10,page 2737,2022)

In the version of the article originally published in the volume 62,issue 10,2022 of Sci.china Mater.(page 2737-2745,https://doi.org/10.1007/s40843-022-2044-3).The chemical shift reported in Figure 5f for the^(11)B solid-state NMR spectra is incorrect because no parameter correction was performed during data processing.