Synthesis of kappa fiber modified graphite carbon nitride with outstanding photocatalytic phenol degradation ability

In this work, kapok fiber (KF) modified graphite carbon nitride (g-C3N4) was prepared by pyrolysis method and the photocatalytic degradation ability of phenol was investigated. XRD, UV–Vis DRS, FT-IR, TEM, XPS, N2 adsorption and PL were used to characterize the as-prepared catalysts. The results showed that KF, as a dual-function modifier, not only provided carbon source for carbon doping, but transformed into activated carbon substrate during calcination, making g-C3N4 grow on it. The KF modified g-C3N4 displays larger specific surface area, thinner layers, stronger visible light absorption capacity, higher separation efficiency and photocatalytic degradation performance. The KF modified g-C3N4 shows the phenol degradation rate constant of 0.258 h−1, which is 4.2 times higher than that of the neat g-C3N4, as well as excellent catalytic stability and structural stability. The excessive calcination temperature results in the low content of g-C3N4 in the catalyst, leading to the decline of photocatalytic performance.