RESUMEN
The efficient polymeric semiconducting photocatalyst for solar-driven sluggish kinetics with multielectron transfer oxygen evolution has spurred scientific interest. However, existing photocatalysts limited by π-conjugations, visible-light harvest, and charge transfer often compromise the O2 production rate. Herein, we introduced an alternative strategy involving a boranil functionalized-based fully π-conjugated ordered donor and acceptor (D-A) covalent organic frameworks (Ni-TAPP-COF-BF2 ) photocatalyst. The co-catalyst-free Ni-TAPP-COF-BF2 exhibits an excellent ~11-fold photocatalytic water oxidation rate, reaching 1404â µmol g-1 h-1 under visible light irradiation compared to pristine Ni-TAPP-COF (123â µmol g-1 h-1 ) alone and surpasses to reported organic frameworks counterpart. Both experimental and theoretical results demonstrate that the push/pull mechanism (metalloporphyrin/BF2 ) is responsible for the appropriate light-harvesting properties and extending π-conjugation through chelating BF2 moieties. This strategy benefits in narrowing band structure, improving photo-induced charge separation, and prolonged charge recombination. Further, the lower spin magnetic moment of M-TAPP-COF-BF2 and the closer d-band center of metal sites toward the Fermi level lead to a lower energy barrier for *O intermediate. Reveal the potential of the functionalization strategy and opens up an alternative approach for engineering future photocatalysts in energy conversion applications.
RESUMEN
The urgent need to develop a sustainable and environmentally friendly method for synthesizing organophosphine compounds is underscored by their extensive applications in organic synthesis, coordination chemistry, medicinal chemistry, and photoelectric materials. Metalated covalent organic frameworks (MCOFs), which seamlessly integrate the inherent photo properties of COF with the catalytic capabilities of metal ions, offer an optimal material for efficient transformation of organics sustainably. In this study, we introduce a simple COF with nickel anchorages (Bpy-COF-NiCl2 ) as a unimolecular metallaphotocatalytic system for effective C-P bond formation. This heterogeneous photocatalyst exhibits superior catalytic performance, achieving yields of up to 95 %, and demonstrates broad substrate tolerance and functional group reactivity. Notably, the metallaphotocatalytic system has demonstrated the capability to process aryl bromides to produce the desired product, a feat not previously reported. Finally, the production and reusability test at the gram scale attests to its superior practicality for designing future organic cross-coupling reactions.
RESUMEN
Artificial photosynthesis is an attractive approach to direct fuel production from sunlight. However, the simultaneous O2 evolution reaction (OER) and CO2 reduction reaction (CDRR) present challenges for product separation and safety. Herein, we propose a strategy to temporally decouple artificial photosynthesis through photoelectrochemical energy storage. We utilized a covalent organic framework (DTCo-COF) with redox-active electron donors (-C-OH moieties) and catalytically active electron acceptors (cobalt-porphyrin) to enable reversible -C-OH/-CâO redox reaction and redox-promoted CO2-to-CO photoreduction. Integrating the COF photocathode with an OER photoanode in a photoelectrochemical device allows the effective storage of OER-generated electrons and protons by -CâO groups. These stored charges can be later employed for CDRR while regenerating -CâO to complete the loop, thus enabling on-demand and separate production of O2 or solar fuels. Our work sets the stage for advancements in decoupled artificial photosynthesis and the development of more efficient solar fuel production technologies.
RESUMEN
Metal-CO2 batteries, an attractive technology for both energy storage and CO2 utilization, are typically classified into organic Li(Na)-CO2 batteries with a high energy density/output voltage and aqueous Zn-CO2 batteries with flexible chemical production. However, achieving both high-efficiency energy storage and flexible chemical production is still challenging. In this study, a reversible hybrid aqueous Li-CO2 battery is developed, integrating Li with an aqueous phase, which exhibits not only a high operating voltage and energy density but also highly selective formic acid production. Based on a Li plate as the anode, NaCl solution as the aqueous electrolyte, solid electrolyte Li1.5 Al0.5 Ge1.5 P3 O12 (LAGP) as a separator and Li+ transporter, and a bifunctional Pd-based electrocatalyst as the cathode, the resulting battery shows a high discharge voltage of up to 2.6â V, an outstanding energy conversion efficiency of above 80 %, and remarkable selectivity of CO2 -to-HCOOH conversion of up to 97 %. The related reaction mechanism is proposed as CO2 +2 Li+2 H+ âHCOOH+2 Li+ .
