Universal,\nTime-Cost-Effective,\nand Inside-Out Strategy\nfor Synthesis of Plant-Based Flow Catalysis Microreactors

The utilization of plant-based flow\ncatalytic microreactors\nhas\nbeen increasingly gaining traction in the fields of water treatment,\nenergy generation, and biotechnological science due to their inherent\nchannel structures, renewable properties, and environmentally friendly\nnature. The conventional outside-in strategy for synthesizing plant-based\nmonolithic microreactors typically entails prolonged hydrothermal\nmodification, extensive chemical usage, or energy-intensive equipment.\nThe present study presents a universal inside-out strategy for the\nrapid synthesis of monolithic catalytic microreactors derived from\nplant materials. This approach enables the direct formation of catalytic\nmetal nanoparticles within specific plant microchannels through regioselective\ndeposition, resulting in reduced chemical usage and an accelerated\nprocess. Moreover, this method effectively minimizes the required\ncatalyst dosage. In this process, the plant monolith’s aligned,\nnarrow, and accessible channels provided a higher contact area, shorter\ndiffusion path, and abundant oxygen-containing functional groups for\nrapid transformation of metal salt precursors into catalytic metal\nnanoparticles with excellent dispersion. The inside-out strategy can\nbe extended to various plant-based monoliths and diverse metal/metal\noxide/MOF materials within the plant monolith, thereby offering a\nfacile, time- and cost-effective universal approach for skillfully\ndesigning plant-based flow microreactors for a wide range of applications.