RESUMO
Metal-organic frameworks (MOFs), with their tunable pore sizes and high surface areas, are gaining prominence in Li metal battery applications, including their use as nanofillers in solid composite electrolytes (SCEs) for enhanced ionic conductivity. Yet, when used in SCEs, individual dispersed MOF particles in isolation as nanofillers can impede efficient ion transport in all-solid-state batteries due to the insufficient supply of ionic transport pathways within SCEs. Here, we introduced a continuous SCE nanofiller with long-range assembly interconnected porous MOFs (IMOF_SCE) for effective ion transport pathway supply along the interface between the nanofiller and the polymer matrix. IMOF_SCE achieved Li-ion conductivity (6.72 × 10-5 S cm-1 at 20 °C) and Li-ion transference number (tLi+ = 0.855), resulting in the improved electrochemical performance of Li metal batteries. Additionally, the Li/LiFePO4 full cell integrated with IMOF_SCE achieved an outstanding stable capacity retention of 98.8% in 300 cycles. This work offers insights into the design strategy of effective nanofillers for SCEs and can be adapted for other porous materials.
RESUMO
Green plants convert sunlight into high-energy chemicals by coupling solar-driven water oxidation in the Z-scheme and CO2 fixation in the Calvin cycle. In this study, formate dehydrogenase from Clostridium ljungdahlii (ClFDH) is interfaced with a TiO2 -coated CuFeO2 and CuO mixed (ClFDH-TiO2 |CFO) electrode. In this biohybrid photocathode, the TiO2 layer enhances the photoelectrochemical (PEC) stability of the labile CFO photocathode and facilitates the transfer of photoexcited electrons from the CFO to ClFDH. Furthermore, inspired by the natural photosynthetic scheme, the photobiocathode is combined with a water-oxidizing, FeOOH-coated BiVO4 (FeOOH|BiVO4 ) photoanode to assemble a wireless Z-scheme biocatalytic PEC device as a semi-artificial leaf. The leaf-like structure effects a bias-free biocatalytic CO2 -to-formate conversion under visible light. Its rate of formate production is 2.45â times faster than that without ClFDH. This work is the first example of a wireless solar-driven semi-biological PEC system for CO2 reduction that uses water as an electron feedstock.