Synthesis of graphene aerogels toward the absorption of liquid and gas pollutants

TL;DR

This study develops cost-effective graphene aerogels via chemical reduction methods and evaluates their effectiveness in absorbing various liquid and gas pollutants, including VOCs and organic solvents.

Contribution

It introduces two synthesis methods for graphene aerogels and demonstrates their high efficiency in pollutant absorption, advancing environmental cleanup materials.

Findings

Graphene aerogels show high absorption capacity for VOCs and organic solvents.

The methods provide a cost-effective way to produce effective pollutant absorbents.

Graphene aerogels significantly reduce pollutant concentrations in microenvironments.

Abstract

Environmental disasters, such as the oil spill in Mexico gulf or, more recently, the Mauritius oil spill caused by a bulk carrier vessel, are some of the ecological issues that the modern society faces frequently. These accidents highlight the need for development of efficient materials that can be employed to eliminate pollutants including crude oil and its derivatives, as well as toxic organic solvents. The objective of the present study is to achieve the synthesis of graphene aerogels with two main methods and to determine their efficiency as absorbents of liquid and gas pollutants. Graphene aerogels were prepared according to the information given by Hong et al. (2015) and Yang et al. (2015). Both methods are based on the chemical reduction of graphene oxide as the first step and the formation of the aerogel as the second, providing a more cost-effective solution and resulting in a lattice structure similar to graphene. The fabricated materials were investigated for their absorption capacity for liquid and gas pollutants. The specimens were mounted in airtight microenvironments saturated with a specific Volatile Organic Compound (VOC). Three VOCs were tested; formaldehyde, acetic acid and hydrochloric acid and the results were based on gravimetric measurements. In order to increase the accuracy of the obtained data, a VOCs sensor was used to measure the change of voltage before and after the introduction of graphene aerogels in a saturated microenvironment. Furthermore, the graphene aerogels were evaluated as absorbents in organic solvents, namely acetone, ethanol and methanol.