Stable construction of layered reduced grapheme oxide/copper sulfide composites on cellulose fibers with hyperbranched polyamide-amine for efficient photocatalytic degradation of organic dyes.

• A novel CuS-based photocatalytic composite paper is prepared. • The load of reduced graphene oxide on fibers relies on hyperbranched polyamide-amine. • Hyperbranched polyamide-amine grafted on fibers induces uniform growth of CuS. • Reduced graphene oxide inhibits the recombination of photogenerated carriers in CuS. • The composite paper exhibited high photocatalytic activity and good reusability. The use of semiconductor-based photocatalysts to degrade organic dyes in water is receiving more and more attention. However, there are still some problems in practical applications, such as high photogenerated carrier recombination rate, difficulty in recovery, and poor reusability. In this study, reduced graphene oxide (rGO)/copper sulfide (CuS) was loaded onto a dialdehyde cellulose fiber (DACF) with the help of hyperbranched polyamide-amine (HPAMAM) to construct a photocatalytic composite paper (DACF/HPAMAM/rGO/CuS paper). Based on the results, HPAMAM was bonded to DACF and rGO via C N and amide bond, and it could act as a nanoreactor to induce uniform and stable growth of CuS. The photocatalytic activity of the as-prepared DACF/HPAMAM/rGO/CuS paper in the degradation of rhodamine B was about 2.7 times that of the composite paper without HPAMAM and rGO (DACF/CuS paper). Such a high performance could be attributed to the improved charge separation efficiency and the stable composite structure of rGO/CuS in the composite paper. DACF/HPAMAM/rGO/CuS paper was also able to demonstrate excellent stability and reusability, which makes it a promising photocatalyst. This work provides a novel strategy for preparing highly efficient and stable photocatalytic composite paper for degradation of organic dyes. [ABSTRACT FROM AUTHOR]