Ni2P Nanosheets on Carbon Cloth: An Efficient Flexible Electrode for Sodium-Ion Batteries.

Transition-metal phosphides have been increasingly investigated because of their high theoretical specific capacity and low potential for sodium storage. Herein, we describe the development of Ni2P nanosheets on carbon cloth (Ni2P Ns/CC), which behaves as a flexible 3D anode for sodium-ion batteries. Such a Ni2P Ns/CC delivers a high capacity of 399 mA h g-1 at 0.2 A g-1. At 2 A g-1, it still delivers 72 mA h g-1 even after 1000 cycles. The impressive performance is attributed to such a self-supported structure. Moreover, a possible conversion reaction mechanism is also carefully revealed.

Cr3C2 Nanoparticle-Embedded Carbon Nanofiber for Artificial Synthesis of NH3 through N2 Fixation under Ambient Conditions.

Industrial production of NH3 heavily depends on the conventional Haber-Bosch process under rigorous conditions with a large amount of energy consumption and carbon emissions. Electrocatalysis exhibits an intriguing prospect for the N2 reduction reaction (NRR) at ambient conditions. In this case, a high-efficiency and low-cost catalyst is paramount. In this letter, Cr3C2 nanoparticles and carbon nanofiber composite (Cr3C2@CNF) are proposed as a noble-metal-free NRR electrocatalyst for converting N2 to NH3 with an excellent selectivity. The optimal Faradic efficiency and NH3 yield rate achieved are as high as 8.6% and 23.9 µg h-1 mgcat.-1 at -0.3 V vs reversible hydrogen electrode in 0.1 M HCl, respectively. Theoretical calculations show a low reaction barrier of merely 0.53 eV in the enzymatic route for this catalyst.

Ceria-reduced graphene oxide nanocomposite as an efficient electrocatalyst towards artificial N2 conversion to NH3 under ambient conditions.

For over a century, NH3 synthesis via the Haber-Bosch process has brought huge energy costs and high CO2 emission. The electrochemical N2 reduction reaction is an environmentally-benign alternative, which can be driven by renewable energy. In this work, CeO2 nanoparticle-reduced graphene oxide nanocomposites (CeO2-rGO) behave as an efficient non-noble-metal N2 reduction reaction electrocatalyst with excellent selectivity. In 0.1 M Na2SO4, CeO2-rGO achieves a high faradaic efficiency of 4.78% and a large NH3 yield of 16.98 µg h-1 mgcat.-1 at -0.7 V vs. reversible hydrogen electrode. The catalytic mechanism was explored using density functional theory calculations.