Horizontal Transport in Ti3C2Tx MXene for Highly Efficient Osmotic Energy Conversion from Saline-Alkali Environments.

Osmotic energy from the ocean has been thoroughly studied, but that from saline-alkali lakes is constrained by the ion-exchange membranes due to the trade-off between permeability and selectivity, stemming from the unfavorable structure of nanoconfined channels, pH tolerance, and chemical stability of the membranes. Inspired by the rapid water transport in xylem conduit structures, we propose a horizontal transport MXene (H-MXene) with ionic sequential transport nanochannels, designed to endure extreme saline-alkali conditions while enhancing ion selectivity and permeability. The H-MXene demonstrates superior ion conductivity of 20.67 S m-1 in 1 M NaCl solution and a diffusion current density of 308 A m-2 at a 10-fold salinity gradient of NaCl solution, significantly outperforming the conventional vertical transport MXene (V-MXene). Both experimental and simulation studies have confirmed that H-MXene represents a novel approach to circumventing the permeability-selectivity trade-off. Moreover, it exhibits efficient ion transport capabilities, addressing the gap in saline-alkali osmotic power generation.

Quenching-induced interfacial amorphous layer containing atomic Ag on Fe2O3 nanosphere for high-performance lithium-ion batteries and mechanism.

The interfacial effect of nanomaterials plays a key role in their electrochemical performance when used in lithium-ion batteries (LIBs), but interfacial modification is a big challenging. Herein, a composite Fe2O3 nanoparticles with atomic Ag/amorphous layers were successfully prepared by co-deposition and subsequent quenching method. Compared to pristine Fe2O3, it maintains a higher capacity and longer cycle life in LIBs, with a capacity of 1150 mAh g-1 after 600 cycles at 0.5 Ag-1, and a long 1800 cycles at a current density of 5 Ag-1 after activation. Detailed experiments and Ex-situ TEM demonstrate that the fusion of surface particles occurred after calcination and quenching treatment, resulting in amorphous layers. The amorphous layer can act as a stabilizer during cycling, which protects the overall nanospheres structure from collapsing and thus leads to ultra-long cycling life. Our findings shed light on the surface modification of nanoscale materials and provides a manner to enhance the electrochemical performance of nanomaterials for LIBs.

Al-Doped Fe2O3 nanoparticles: advanced anode materials for high capacity lithium ion batteries.

Al-Doped Fe2O3 (Al-Fe2O3) nanoparticles with a reconstructed electronic structure, oxygen vacancy and modified physical/chemical features are synthesized and used as an advanced anode for Lithium Ion Batteries (LIBs).