Porous Framework Materials for C1 Biotransformation

ABSTRACT: The bioconversion of C1 compounds (CO₂, methane, methanol, etc.) constitutes a crucial pathway for green biomanufacturing. However, the process efficiency is constrained by several challenges, including the difficult capture of gaseous substrates, instability of biocatalysts, and the high cost as well as operational complexity of cofactor regeneration. Porous framework materials offer promising solutions due to their high specific surface area, tunable pore structures, and ease of functionalization. This review provides a systematic and forward-looking analysis that moves beyond the conventional view of porous frameworks as simple immobilization matrices. We distinctly highlight their emerging multifunctional and integrative roles in C1 bioconversion, emphasizing several novel strategic contributions: (1) Serving as intelligent immobilization carriers that not only enhance biocatalyst stability and recyclability but also concurrently enable efficient C1 substrate enrichment and localized concentration; (2) Facilitating synergistic energy conversion by interfacing with photocatalysis or electrocatalysis to enable in-situ and sustainable cofactor regeneration, thereby addressing a key economic bottleneck; (3) Actively regulating microbial metabolism and community dynamics through tailored material-microbe interactions, optimizing carbon flux and system resilience; and (4) Mimicking natural enzymes to create robust and tunable biomimetic catalysts for C1 conversion under non-physiological conditions. Remaining challenges, such as mass transfer limitations, the scalability of material synthesis, and the integration of hybrid systems, are analyzed through the lens of these advanced functionalities. We conclude that the synergistic and rational integration of synthetic biology-designed biocatalysts with engineered multifunctional frameworks represents a paradigm shift, paving the way for efficient, stable, and high-value utilization of C1 resources.