Preparation of Au0.5Pt0.5/MnO2/cotton catalysts for decomposition of formaldehyde

Powder Au0.5Pt0.5/MnO2 and Au0.5Pt0.5/ MnO2/cotton catalysts were successfully prepared by facile methods. The as-prepared catalysts were char- acterized by means of XRD, SEM, TEM, and TGA. Au0.5Pt0.5 alloy NPs were evenly dispersed on the surface of nest-like MnO2 and no agglomeration was observed. The powder Au0.5Pt0.5/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 Au0.5Pt0.5/MnO2/cotton catalysts showed excellent catalytic activities for oxidative decomposi- tion of formaldehyde (HCHO). 15 wt% Au0.5Pt0.5/ 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 Au1-xPtx NPs and MnO2, and synergistic effect between Au0.5Pt0.5/ MnO2 and cotton are considered to be the main reasons for the observed high catalytic activity of Au0.5Pt0.5/MnO2/cotton catalysts. The Au0.5Pt0.5/ MnO2/cotton catalysts can not only avoid the disad- vantages of power catalysts but also improve the catalytic activity; these advantages indicate that Au0.5Pt0.5/MnO2/cotton catalysts have promising potentials in practical applications.