Heterogeneous solid base catalysts have attracted widespread attention for various reactions from the perspective of green and economy chemistry due to their advantages such as low corrosiveness, high reaction efciency, and easy separation. The unique properties of polyacrylonitrile fbers (PANF) such as good mechanical strength and a surface rich in cyanine and economy make them suitable catalytic supports. Herein, potassium oxide was introduced into PANF by redox strategy. Characterization using XRD, FT-IR, solid-state ¹³C NMR, XPS, SEM, CO₂-TPD, etc. confrmed the successful preparation of this heterogeneous base catalyst and the participation of PANF in the redox process of KNO₃ to promote the decomposition of KNO₃. The acquired catalyst showed obvious activity for the oxidation of methylene compounds and the yield of fuorenones can reach 100% at 100 ℃. This strategy provides a new development path for the application of PANF and the synthesis of heterogeneous bases.