Mechanistic Study of Highly Active Bifunctional Double-Atom Electrocatalysts for Oxygen Reduction and Oxygen Evolution Reactions.

Dual-atom catalysts (DACs) can be very effective for catalyzing both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). Herein, we present theoretical evidence of a new class of highly active DACs, namely, the double-atom embedded in nitrogen-doped graphene sheet 2M-N-C (M = Mn, Fe) on the basis of density functional theory calculations. Importantly, we find that the double active sites of 2M-N-C DACs entail an unconventional catalytic reaction pathway for ORR and OER.

Anchoring Active Li Metal in Oriented Channel by In Situ Formed Nucleation Sites Enabling Durable Lithium-Metal Batteries.

Lithium metal is the ultimate anode material for pursuing the increased energy density of rechargeable batteries. However, fatal dendrites growth and huge volume change seriously hinder the practical application of lithium metal batteries (LMBs). In this work, a lithium host that preinstalled CoSe nanoparticles on vertical carbon vascular tissues (VCVT/CoSe) is designed and fabricated to resolve these issues, which provides sufficient Li plating space with a robust framework, enabling dendrite-free Li deposition.

Role of transition metal d-orbitals in single-atom catalysts for nitric oxide electroreduction to ammonia.

Recently, surging interests exist in direct electrochemical ammonia (NH) synthesis from nitric oxide (NO) due to the dual benefit of NH synthesis and NO removal. However, designing highly efficient catalysts is still challenging. Based on density functional theory, the best ten candidates of transition-metal atoms (TMs) embedded in phosphorus carbide (PC) monolayer is screened out as highly active catalysts for direct NO-to-NH electroreduction.

Inducing Fe 3d Electron Delocalization and Spin-State Transition of FeN Species Boosts Oxygen Reduction Reaction for Wearable Zinc-Air Battery.

Transition metal-nitrogen-carbon materials (M-N-Cs), particularly Fe-N-Cs, have been found to be electroactive for accelerating oxygen reduction reaction (ORR) kinetics. Although substantial efforts have been devoted to design Fe-N-Cs with increased active species content, surface area, and electronic conductivity, their performance is still far from satisfactory. Hitherto, there is limited research about regulation on the electronic spin states of Fe centers for Fe-N-Cs electrocatalysts to improve their catalytic performance.

Surface Engineering of Flower-Like Ionic Liquid-Functionalized Graphene Anchoring Palladium Nanocrystals for a Boosted Ethanol Oxidation Reaction.

The development of low-cost and high-performance electrocatalyst-supporting materials is desirable and necessary for the ethanol oxidation reaction (EOR). Here, we report a facile and universal template-free approach for the first time to synthesize three-dimensional (3D) flower-like ionic liquid-functionalized graphene (IL-RGO). Then, the crystalline Pd nanoparticles were anchored on IL-RGO by a simple wet chemical growth method without a surfactant (denoted as Pd/IL-RGO).

Electrochemical CO Reduction to C Products on Single Nickel/Cobalt/Iron-Doped Graphitic Carbon Nitride: A DFT Study.

Electrocatalytic CO reduction reaction (CRR) is one of the most promising strategies to convert greenhouse gases to energy sources. Herein, the CRR was applied towards making C products (CO, HCOOH, CH OH, and CH ) on g-C N frameworks with single Ni, Co, and Fe introduction; this process was investigated by density functional theory. The structures of the electrocatalysts, CO adsorption configurations, and CO reduction mechanisms were systematically studied.

Encapsulating Co P@C Core-Shell Nanoparticles in a Porous Carbon Sandwich as Dual-Doped Electrocatalyst for Hydrogen Evolution.

A highly efficient and pH-universal hydrogen evolution reaction (HER) electrocatalyst with a sandwich-architecture constructed using zero-dimensional N- and P-dual-doped core-shell Co P@C nanoparticles embedded into a 3 D porous carbon sandwich (Co P@N,P-C/CG) was synthesized through a facile two-step hydrothermal carbonization and pyrolysis method. The interfacial electron transfer rate and the number of active sites increased owing to the synergistic effect between the N,P-dual-doped Co P@C core-shell and sandwich-nanostructured substrates. The presence of a high surface area and large pore sizes improved the mass-transfer dynamics.

Label-Free LSPR Detection of Trace Lead(II) Ions in Drinking Water by Synthetic Poly(mPD-co-ASA) Nanoparticles on Gold Nanoislands.

Using self-assembly gold nanoislands (SAM-AuNIs) functionalized by poly(m-phenylenediamine-co-aniline-2-sulfonic acid) (poly(mPD-co-ASA)) copolymer nanoparticles as specific receptors, a highly sensitive localized surface plasmon resonance (LSPR) optochemical sensor is demonstrated for detection of trace lead cation (Pb(II)) in drinking water. The copolymer receptor is optimized in three aspects: (1) mole ratio of mPD:ASA monomers, (2) size of copolymer nanoparticles, and (3) surface density of the copolymer. It is shown that the 95:5 (mPD:ASA mole ratio) copolymer with size less than 100 nm exhibits the best Pb(II)-sensing performance, and the 200 times diluted standard copolymer solution contributes to the most effective functionalization protocol.