Three-Dimensional Octahedral Nanocrystals of Cu2O/CuF2 Grown on Porous Cu Foam Act as a Lithophilic Skeleton for Dendrite-Free Lithium Metal Anode

Metallic-lithium (Li) anodes are highly sought-after for next-generation energy storage systems due to their high theoretical capacity and low electrochemical potential. However, the commercialization of Li anodes faces challenges, including uncontrolled dendrite growth and volume changes during cycling. To address these issues, we developed a novel three-dimensional (3D) copper current collector. Here, we propose a two-step method to fabricate Cu2O/CuF2 octahedral nanocrystals (ONCs) onto 3D Cu current collectors. The resulting Cu foam with distributed ONCs provides active electrochemical sites, promoting uniform Li nucleation and dendrite-free Li deposition. The stable Cu2O/CuF2 ONCs@CF metallic current collector serves as a reliable host for dendrite-free lithium metal anodes. Additionally, the highly porous copper foam with a preconstructed conductive framework of Cu2O/CuF2 ONCs@CF effectively reduces local current density, suppressing volume changes during Li stripping and plating. The symmetric cell using Cu2O/CuF2 ONCs@CF metallic current collector exhibits excellent stability, maintaining over 1600 h at 1 mA cm-2 and a highly stable Coulombic efficiency of 98% over 100 cycles at the same current density, outperforming Li@CuF metallic current collectors. Furthermore, in a full-cell configuration paired with nickel-rich layered oxide cathode materials (Li@Cu2O/CuF2 ONCs@CF//NMC-811), the proposed setup demonstrates exceptional rate performance and an extended cycle life. In conclusion, our work presents a promising strategy to address Li anode challenges and highlights the exceptional performance of the Cu2O/CuF2 ONCs@CF metallic current collector, offering potential for high-capacity and long-lasting lithium-based energy storage systems.

Reline deep eutectic solvent mediated synthesis of lanthanum titanate for heavy metal remediation and photocatalytic degradation

Toxic heavy metal and dye contamination are potential threats that mutilate the essential triad of life; air, water and soil. Despite commercial applicability and importance, the over accumulation of these noxious toxicants has become a disturbing concern. As a result, their remediation has drawn greater fascination leading to the inexplicable quest for a material which can act as both an adsorbent and as a photocatalyst. The present work highlights a novel solid-state technique assisted with reline (Choline chloride: Urea) deep eutectic solvent for the synthesis of lanthanum titanate. The synthesized material was established with physical characterizations like PXRD, FT-IR, UV-DRS, BET, XPS, HR-SEM and TEM techniques. Further, the ruptured petal-like lanthanum titanate was integrated as an adsorbent for the removal of lead (Pb), arsenic (As) and chromium (Cr) heavy metals. The adsorbent presented increased adsorption efficiencies of 96, 74 and 71% towards Pb, As and Cr respectively. Dependence of the degradation efficiency over concentration, pH, contact time and competitive environments were analyzed and inferred. Furthermore, lanthanum titanate was used for the photocatalytic degradation of reactive black (RB5), red (RR198) and yellow (RY145) dyes. The degradation efficiencies were found to be 68.31, 85.2 and 96.8% for RB5, RR198 and RY145 dyes respectively. Variation in concentration and pH of the dye solutions were examined and reaction kinetics was also proposed. In conclusion, the as synthesized lanthanum titanate is assured to play dual roles as a versatile cost-effective adsorbent for the remediation of heavy metals and as a potential candidate for photocatalytic degradation.

Direct fabrication of nanoporous graphene from graphene oxide by adding a gasification agent to a magnesiothermic reaction

CaCO3 acts as a gasification agent during magnesiothermic reduction of graphene oxide, thus preventing the newly formed graphene from restacking. The surface area of the obtained graphene increases from 66 m(2) g(-1) to 603 m(2) g(-1) by adding CaCO3 with a high yield of ∼70% based on the carbon content in graphene oxide.