Disruptive Strategy To Fabricate Three-Dimensional Ultrawide Interlayer Porous Carbon Framework-Supported Prussian Blue Nanocubes: A Carrier for NiFe-Layered Double-Hydroxide toward Oxygen Evolution

Abstract

We, for the first time, offer a unique and disruptive strategy to prepare N-doped three-dimensional porous carbon framework-supported well-defined Fe4[Fe(CN)6]3 nanocubes (indicated as PB@N-PCFs). The carbon frameworks hold an ultrawide interlayer spacing of 0.385–0.402 nm for the (002) planes of graphite and ultrahigh graphitization. Furthermore, PB@N-PCFs are used as a carrier to grow NiFe-layered-double-hydroxide nanosheet arrays (denoted as NiFe-LDH/PB@N-PCFs) in situ, where the interlayer spacing for the (002) planes of graphite can be expanded as high as 0.457 nm in the carbon frameworks. Moreover, NiFe-LDH/PB@N-PCFs shows excellent electrocatalytic performance toward oxygen evolution in terms of activity, kinetics, and durability, elegantly rivaling the state-of-the-art RuO2. More profoundly, after 3000 cycle cyclic voltammetry scans, NiFe-LDH/PB@N-PCFs still display far more desirable activity with respect to initial NiFe-LDH/PB@N-PCFs. We believe that the PB@N-PCFs and PB@N-PCFs-based composites with ultrahighly graphitized and large interlayer spacing N-PCFs can find more places in electrochemistry-related applications such as Na/K-ion batteries, electrocatalysis, and electrochemical sensors.

Sodium Tartrate-Assisted Synthesis of High-Purity NiFe2O4 Nano-Microrods Supported by Porous Ketjenblack Carbon for Efficient Alkaline Oxygen Evolution

“…Dwindling fossil-fuel reserves, together with environmental damage caused by the burning of fossil-fuels for energy, demand the rapid development of renewable energy technologies. − Hydrogen represents a very promising energy carrier to replace fossil-fuels due to its high energy density and zero carbon emissions when used in hydrogen fuel cells. − Electrochemical water splitting using renewably generated electricity is widely regarded as the most promising and viable route for high-purity hydrogen production at scale. − The anodic reaction in overall water splitting is the oxygen evolution reaction (OER), a sluggish four-electron-transfer process that typically requires a high overpotential to drive it. − To achieve a high electrical energy utilization efficiency and lower the overpotential, efficient OER electrocatalysts are indispensable. − To date, expensive precious metal oxide-based catalysts, such as RuO 2 and IrO 2 , offer the best OER activity. , However, these catalysts suffer from poor durability under alkaline OER conditions. These factors motivate the search for alternative, low-cost, high activity, and durable OER catalysts to replace RuO 2 and IrO 2 . − …”