Design a Novel Recyclable Fe 3 O 4 @SiO 2 ‐TGDM@Ni MICOF Electrode for CO 2 Trap, Electrolyte, and Catalyst for Electro‐Carboxylation Reaction

Abstract

ABSTRACT The design and development of high‐performance electrocatalytic systems featuring multiple functionalities, excellent recyclability, and reusability constitute a vital and essential advancement in the field of green chemistry. Such innovative approaches significantly mitigate environmental impacts by substantially reducing the discharge of toxic and hazardous pollutants into ecosystems, while concurrently lowering the operational and production costs associated with chemical processes. In alignment with this principle, a novel magnetic electrode based on Fe 3 O 4 @SiO 2 ‐TGDM@Ni was strategically designed and developed. Within this core‐shell architecture, the Fe 3 O 4 @SiO 2 component imparts strong magnetic properties that facilitate straightforward recovery and repeated use of the electrode through simple magnetic separation. The triaminoguanidine dimethoxybenzene (TGDM) layer simultaneously functions as an electrolyte mediator/support and a co‐catalytic promoter, enhancing overall system efficiency. Meanwhile, the Ni NPs serve as the primary electrocatalyst, and thanks to the integrated magnetic recoverability, the entire electrode can be easily retrieved, reused, and assessed for minimal metal leaching. The practical performance of this multifunctional electrode was rigorously evaluated in the electrocarboxylation reaction. The electrochemical synthesis of 2‐phenylpropanoic acid derivatives 3(a–l) was performed under remarkably mild conditions (room temperature, iPrOH) using a constant current of 7 mA for just 1 h. These optimized conditions afforded the products in excellent isolated yields between 90% and 97%. Impressively, it maintained robust catalytic activity and structural integrity across up to 10 consecutive recycling cycles with negligible performance degradation. The core‐shell structured Fe 3 O 4 @SiO 2 ‐TGDM@Ni material underwent comprehensive characterization using a wide array of techniques, including SEM, EDS, TEM, FT‐IR, BET, TGA, VSM, XPS, CV, ICP‐OES and mass spectrometry. Similarly, the resulting 2‐phenylpropanoic acids 3(a‐l) were fully identified and confirmed through melting point determination, 1 H NMR, 13 C NMR spectroscopy, and elemental analysis (CHN).