Preparation of Au_0.5Pt_0.5/MnO₂/cotton catalysts for decomposition of formaldehyde

Powder Au_0.5Pt_0.5/MnO₂ and Au_0.5Pt_0.5/MnO₂/cotton catalysts were successfully prepared by facile methods. The as-prepared catalysts were characterized by means of XRD, SEM, TEM, and TGA. Au_0.5Pt_0.5 alloy NPs were evenly dispersed on the surface of nest-like MnO₂ and no agglomeration was observed. The powder Au_0.5Pt_0.5/MnO₂ catalyst was adhered to the surface of cotton fibers, and the practical loading amount first increases, and then levels off with increase of the theoretical loading dosage. The Au_0.5Pt_0.5/MnO₂/cotton catalysts showed excellent catalytic activities for oxidative decomposition of formaldehyde (HCHO). 15 wt% Au_0.5Pt_0.5/MnO₂/cotton has the highest catalytic activity and the temperature for complete decomposition of HCHO is 120 °C. The valence states of MnO₂, MnO₂ porous structures, synergistic effect between Au_1−xPt_x NPs and MnO₂, and synergistic effect between Au_0.5Pt_0.5/MnO₂ and cotton are considered to be the main reasons for the observed high catalytic activity of Au_0.5Pt_0.5/MnO₂/cotton catalysts. The Au_0.5Pt_0.5/MnO₂/cotton catalysts can not only avoid the disadvantages of power catalysts but also improve the catalytic activity; these advantages indicate that Au_0.5Pt_0.5/MnO₂/cotton catalysts have promising potentials in practical applications. Graphical Abstract: . .