Facile Synthesis and Integration of Poly(vinyl alcohol) Sponge-Supported Metal Nanocatalysts on a Microfluidic Chip Enable a New Continuous Flow Multireactor Nanocatalysis Platform for High Efficiency and Reusability Catalysis

A new poly(vinyl alcohol) (PVA) sponge-supported nanocatalysis platform on a continuous-flow microfluidic multi reactor device was constructed for high-efficiency and high reusability catalytic degradation of environmental pollutants. PVA sponge-supported metal nanoparticle catalysts (MNPs/PVA) were prepared by a simple improved impregnation self-assembly method, without any complicated surface modification. The MNPs/PVA catalysts were further integrated on a multireactor microfluidic device to form a continuous flow (CF) reactor platform (MNPs/PVA/chip) for simultaneous catalytic degradation of pollutants with two different nanocatalysts. After condition and catalyst optimizations, the catalytic activities of AuNPs/PVA and CoNPs/PVA were evaluated on this continuous flow microfluidic multireactor platform, by using p-nitrophenol (4-NP) as a model organic pollutant. Both catalysts exhibited outstanding catalytic efficiency (e.g., 100% for fresh catalysts), and the strong interactions between MNPs and PVA ensured high reusability (e.g., >20 cycles). After 20 cycles of catalysis, the optimal catalyst AuNPs/PVA still maintained a high catalytic efficiency of 97.6%. Compared to AuNPs/PVA-5, the cost-effective CoNPs/PVA catalyst exhibited similar catalytic performance within the first 10 cycles, while AuNPs/PVA showed better stability for long-term use. Hence, this continuous flow catalytic platform that combines the advantages of porous material-supported nanocatalysts with microfluidic devices has tremendous potential for various cost-effective environmental research and practical applications.

Automated summary

A new continuous flow microfluidic multireactor device with a poly(vinyl alcohol) (PVA) sponge-supported nanocatalysis platform was developed for efficient and reusable catalytic degradation of environmental pollutants. The integration of PVA sponge-supported metal nanoparticle catalysts on a multireactor microfluidic device enabled simultaneous catalytic degradation of pollutants with different nanocatalysts. The optimized AuNPs/PVA and CoNPs/PVA catalysts demonstrated outstanding catalytic efficiency and high reusability, making this platform promising for cost-effective environmental research and practical applications.