Integrated 3D pore architecture design of bio-based engineered catalysts and adsorbents: preparation, chemical doping, and environmental applications

An integrated strategy combining 3D architecture design and chemical doping holds great promise for enhancing the performance of bio-based engineered carbon materials in environmental applications. This review paper critically examines the use of integrated hierarchical porous carbon derived from biomass (bio-based IHPC) as an engineered catalyst and adsorbent for environmental purposes. The hierarchically interconnected pore architectures can reduce the electrical resistance and shorten the diffusion pathway, which is beneficial for the transport of ions/molecules. Additionally, the high pore volume, large specific surface area, and abundant active sites contribute to the high capacity for ion and molecule capture. The bio-based IHPC with 3D interconnected hierarchical porous structures can be obtained through non-templating, hard-templating and self-templating strategies. Chemical doping can further create functional groups and active sites on the bio-based IHPC surface, resulting in an abundance of reaction and interaction with pollutants. In particular, the surface properties of bio-based IHPCs can be further modified by heteroatom doping or metal (hydr)oxide coating. The review demonstrates the efficiency of bio-based IHPC as an engineered catalyst and adsorbent in various environmental applications. These applications include the removal of toxic trace elements and organic pollutants, carbon capture, enhancement of anaerobic digestion processes, antimicrobial treatment, and oil-water separation. The paper thoroughly discusses the influence mechanisms of pore architectures and chemical doping on the performance of bio-based IHPC in these applications. Finally, the paper concludes by presenting promising research directions for the preparation and application of bio-based IHPC.