Robust Pseudocapacitive Sodium Cation Intercalation Induced by Cobalt Vacancies at Atomically Thin Co Se /Graphene Heterostructure for Sodium-Ion Batteries.

Electronic structure engineering on electrode materials could bring in a new mechanism to achieve high energy and high power densities in sodium ion batteries. Herein, we design and create Co vacancies at the interface of atomically thin CoSe /graphene heterostructure and obtain Co Se /graphene heterostructure electrode materials that facilitate significant Na intercalation pseudocapacitance. Density functional theory (DFT) calculation suggests that the Na adsorption energy is dramatically increased, and the Na diffusion barrier is remarkably reduced due to the introduction of Co vacancy.

DFT-Guided Design and Fabrication of Carbon-Nitride-Based Materials for Energy Storage Devices: A Review.

Carbon nitrides (including CN, CN, CN, CN, CN, and CN) are a unique family of nitrogen-rich carbon materials with multiple beneficial properties in crystalline structures, morphologies, and electronic configurations. In this review, we provide a comprehensive review on these materials properties, theoretical advantages, the synthesis and modification strategies of different carbon nitride-based materials (CNBMs) and their application in existing and emerging rechargeable battery systems, such as lithium-ion batteries, sodium and potassium-ion batteries, lithium sulfur batteries, lithium oxygen batteries, lithium metal batteries, zinc-ion batteries, and solid-state batteries. The central theme of this review is to apply the theoretical and computational design to guide the experimental synthesis of CNBMs for energy storage, i.

Polypyrrole Hollow Microspheres with Boosted Hydrophilic Properties for Enhanced Hydrogen Evolution Water Dissociation Kinetics.

The water dissociation step (HO + M + e → M - H + OH) is a crucial one toward achieving high-performance hydrogen evolution reaction (HER). The application of electronic conducting polymers (ECPs), such as polypyrrole (PPy), as the electrocatalyst for HER is rarely reported because of their poor adsorption energy per water molecule, which hinders the Volmer step. Herein, we strongly enrich PPy hollow microspheres (PPy-HMS) with attractive HER activity by enhancing their hydrophilic properties through hybridization with good water affinity SiO.

Highly Conductive Two-Dimensional Metal-Organic Frameworks for Resilient Lithium Storage with Superb Rate Capability.

Redox-active organic cathode materials have drawn growing attention because of the broad availability of raw materials, eco-friendliness, scalable production, and diverse structural flexibility. However, organic materials commonly suffer from fragile stability in organic solvents, poor electrochemical stability in charge/discharge processes, and insufficient electrical conductivity. To address these issues, using Cu(II) salt and benzenehexathiolate (BHT) as the precursors, we synthesized a robust and redox-active 2D metal-organic framework (MOF), [Cu(CS)], namely, Cu-BHT.

1D/2D CN/Graphene Composite as a Preferred Anode Material for Lithium Ion Batteries: Importance of Heterostructure Design via DFT Computation.

Graphene is commonly used to improve the electrochemical performance of electrode materials in rechargeable batteries by forming graphene-based heterostructures. Two-dimensional graphitic carbon nitride (CN) is an analogue of graphene, and it is often used to form 1D/2D and 2D/2D CN/graphene heterostructures. However, a theoretical understanding of the heterointerface in these heterostructures and how this affects their electrochemical performance is lacking.

Hierarchical CoO@N-Doped Carbon Composite as an Advanced Anode Material for Ultrastable Potassium Storage.

Cobalt oxide (CoO) delivers a poor capacity when applied in large-sized alkali metal-ion systems such as potassium-ion batteries (KIBs). Our density functional theory calculation suggests that this is due to poor conductivity, high diffusion barrier, and weak potassium interaction. N-doped carbon can effectively attract potassium ions, improve conductivity, and reduce diffusion barriers.