▎ 摘　　要

The presence of organic dye molecules and heavy metal ions in water causes ecological and public health problems. Therefore, remediation of water/wastewater contaminated with organic dye molecules and toxic metal ions is of importance. Herein, a reduced graphene oxide (RGO)ehydroxyapatite (Hat) (1D-2D) hybrid composite was fabricated through a hydrothermal process and applied for the adsorption of methyl orange (MO) and hexavalent chromium (Cr(VI)) from water. The as-fabricated RGO-Hat hybrids were characterized using FTIR, XRD, HR-TEM, SEM, XPS, EDAX, and TGA-DSC analytical techniques. The influencing parameters of adsorption performance, namely solution pH, contact time, and co-interfering ions, were explored to obtain the maximum adsorption capacity of contaminants from the solideliquid interface. Batch studies revealed that MO and Cr(VI) adsorption followed the pseudo-second-order kinetic and the Langmuir isotherm models. The adsorption capacity was 49.14 and 45.24 mg g(-1) for MO and Cr(VI), respectively. The adsorption of such ions over RGO-Hat hybrids was mainly driven by several uptake mechanisms viz, electrostatic force of attraction, pi-pi interactions, and hydrogen bonding. Thus, this study demonstrated that the RGO-Hat hybrid is a potential candidate for the treatment of MO and Cr(VI) from water. (C) 2021 Elsevier Ltd. All rights reserved.