# 3D rGO and rGO/TiO2–Modified Melamine Sponges: Sorbents for Oil and Emerging Organic Pollutant Removal

## TL;DR

This paper presents a new method to modify melamine sponges with graphene and titanium dioxide for removing oil and pollutants from water.

## Contribution

The study introduces a sustainable, multifunctional sorbent combining rGO and TiO2 for oil and organic pollutant removal.

## Key findings

- The modified sponges showed an oil uptake capacity of 85 times their own weight.
- The material achieved high adsorption efficiencies for pollutants like methylene blue and ibuprofen.
- The sponges maintained high removal efficiency after nine reuse cycles.

## Abstract

Environmental disasters resulting from the exploitation
of natural
resources, such as oil spills, have severe and lasting impacts on
ecosystems. In this work, melamine sponges were modified with reduced
graphene oxide (rGO) and titanium dioxide nanosheets (TiO2) to develop multifunctional materials for environmental remediation.
Prior to TiO2 modification, the sponges were coated with
rGO of different sheet sizes to evaluate the influence of rGO dimensions
on surface coverage and material properties. Graphene oxide was reduced
using ascorbic acid as a green reducing agent, and the process was
accelerated in a microwave reactor. The resulting 3D material exhibited
hydrophobic and oleophilic characteristics, enabling efficient and
selective oil absorption from water. Structural and morphological
characterizations confirmed the successful modification of the sponge,
which displayed an outstanding oil uptake capacity of approximately
85 times its own weight. In addition to oil sorption, the material
demonstrated high adsorption efficiencies for various organic contaminants,
including methylene blue (95%), rhodamine B (99%), ibuprofen (75%),
bisphenol A (71%), and tetracycline (73%). It also exhibited excellent
photocatalytic activity toward methylene blue (95%) and maintained
remarkable reusability, preserving high removal efficiencies after
nine consecutive cycles for RhB (97%), IBP (71%), and TC (70%). These
results highlight the potential of rGO/TiO2-modified melamine
sponges as versatile and sustainable platforms for oil–water
separation and the remediation of organic pollutants in aqueous media.