Dynamic Intelligent Cu Current Collectors for Ultrastable Lithium Metal Anodes

Three-dimensional (3D) current collectors have shown great potential in realizing dendrite-free lithium (Li) metal anodes. However, the rigid 3D current collectors could not simultaneously suppress Li dendrite growth and allow Li plating/stripping under high capacities and large current densities. Here, we report a dynamic intelligent Cu (DICu) current collector that dynamically accommodates the volume change by changing the packing density of the assembled particles. The Li/DICu electrode achieves a high Coulombic efficiency of 99.6% after 800 cycles. The symmetrical cell shows exceptional cycling stability under the high current density of 10 mA cm^-2. Notably, when assembled in full-cell batteries, the Li/DICu|LiFePO₄ battery maintains a specific capacity of 139.5 mAh g^-1 at 1 C for 500 cycles, and the Li/DICu|S battery delivers a specific capacity of 804 mAh g^-1 after 500 cycles at 0.5 C, corresponding to the best performance among Li metal batteries with Cu-based current collectors to date.

Interconnected Molybdenum Carbide-Based Nanoribbons for Highly Efficient and Ultrastable Hydrogen Evolution

Electrocatalytic hydrogen evolution reaction (HER) is of great significance to produce clean, sustainable, and cost-effective hydrogen. However, the development of low-cost and high-efficiency non-noble-metal catalysts with a combination of superior catalytic activity and long-time stability still remains a challenge. Herein, we demonstrate a rationally designed three-dimensional architecture assembled from one-dimensional molybdenum carbide (MoC)-based nanoribbons where the MoC nanoparticles are embedded within the nitrogen-doped crystallized carbon nanolayers (MoC@NC nanoribbon). Such unique architecture of the MoC@NC nanoribbon not only provides abundant edge active sites and multielectron pathways for efficient mass/charge transportation but also greatly accelerates the hydrogen release from the reaction surface, thus boosting its electrocatalytic performances for HER either in an acid or in an alkaline aqueous solution. This advance provides a promising candidate toward the replacement of the noble-metal-based catalysts for a highly stable and efficient HER electrocatalysis.