X-ray diffraction (XRD) patterns were employed to investigate the crystallinity of COF@bio and its composites. Both COF@bio and its composites displayed several characteristic peaks, indicating the crystallinity of the materials (Fig. ). The imperfect crystallinity of COF@bio may be related to the high reactivity of DFF, resulting in a lack of "self-healing" and "error adjustment" processes. When COF@bio in-situ grown on the exterior of CNT, COF@bio-20 exhibited similar characteristic XRD peaks to COF@bio, confirming the successful preparation of COF@bio with CNT composites to a certain extent. Subsequently, the specific surface area of the pure COF@bio, COF@bio composites, and CNT were characterized by the N2 adsorption/desorption analysis. Fig. -S7 shown the N2 sorption/ desorption isotherms of COF@bio, CNT and their composites, with the Brunauer-Emmett-Teller (BET) surface areas calculated as follows: 6 m 2 g -1 for pure COF@bio, 13 m 2 g -1 for COF@bio-20, 17 m 2 g -1 for COF@bio-40, 294 m 2 g -1 for CNT (Table ). The average pore sizes were approximately 30.34 nm for pure COF@bio, 19.29 nm for COF@bio-20, 10.63 nm for COF@bio-40, and 7.45 nm for CNT. An interesting phenomenon observed was that as the mass ratio of CNT increased, the specific surface area of the COF@bio composites grew larger. In contrast, the average pore size exhibited an opposite trend, decreasing significantly. This phenomenon was attributed to the high specific surface area and uniform pore size of the CNT, which enhanced conductivity and dispersed COF@bio, thereby increasing the utilization rates of active sites. Thermogravimetric analysis (TGA) was conducted to evaluate the stability of the materials. As shown in Fig. , COF@bio-20 and COF@bio-40 exhibited better thermal stability than pure COF@bio, which can be attributed to the excellent stability of CNT. Thus, the COF@bio composites can withstand harsh conditions while maintaining a stable chemical structure.