Photocatalytic activity of hydroxyapatite deposited graphene nanosheets under illumination to sunlight

Abstract Herein, an intelligent, sunlight active photocatalyst, GR-HAP has been developed by synthetic modification of graphene (GR) nanosheets through in-situ deposition of hydroxyapatite (HAP). The photocatalytic efficiency of GR-HAP was evaluated by degradation of industrially important and versatile used azo dyes, viz., methyl orange, methylene blue and rhodamine B under illumination to natural sunlight. GR-HAP was capable in complete degradation all dyes in presence of sunlight. It was estimated that with GR-HAP, rate for degradation of anionic dye, methyl orange was higher than cationic dyes, methylene blue and rhodamine B. Further, degradation rate of dyes was quantified using Langmuir–Hinshelwood (L–H) model and it found that degradation of dyes proceed through pseudo-first-order reaction. In addition to excellence in photocatalytic activity, GR-HAP possessed prominent stability against photocorrosiveness and photobleaching.