|Eny Kusrini||Department of Chemical Engineering, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia|
|Eko Adhi Setiawan||Department of Electrical Engineering, Faculty of Engineering, Universitas Indonesia, Kampus Baru UI Depok 16424, Indonesia|
|Mohammed Ali Berawi||Department of Civil Engineering, Faculty of Engineering, Universitas Indonesia, Kampus UI Depok, Depok 16424, Indonesia|
The pursuit of new materials and engineering methods for energy sustainability has become an essential, exciting research issue. Various studies have been conducted to explore new materials and develop new engineering methods to process new material or re-use waste material for new energy resources. However, new materials cannot be used directly as sources of new energy; some of their characteristics need to be explored to determine their energy potentials. New engineering methods are also needed to process and prepare new materials, and advanced techniques are needed to pre-process new materials to remove unused residues that reduce their performance. Hence, finding new materials and innovating engineering methods to process them are inextricably linked topics.
Graphene is a particularly promissing new material because of its extraordinary mechanical, electrical, thermal, and physical properties, providing many potential applications in various fields. Graphene is allotrope of carbon with two-dimensional crystal structure comprising planar sheets of sp2-bonded carbon atoms densely packed in a honeycomb crystal lattice. The chemical oxidation of graphite followed by its reduction has become the most potential method and economical process to produce graphene in bulk quantity. To utilize it in some industrial applications, such as a catalyst, an additive in water-based drilling fluid, and in advanced material technology, its dispersion is an important issue, since it is usually applied using solvent-assisted techniques, such as layer-by-layer assembly, spin-coating, and filtration. To disperse graphene well, chemical modifications can be applied on its surface to enhance the capability of graphene oxides to disperse in water, but the requisite oxygen-containing groups significantly decrease their electrical properties. To overcome this problem, other functional groups have been introduced to the graphene structure. Graphene can be functionalized with covalent and non-covalent modification techniques, both of which follow the surface modification by reduction. Thermal stability, reduced fluid loss, and lubricating capabilities are the main advantages of adding graphene to drilling fluid.
Other issues in many countries include the contamination of anions, such
as fluoride, and heavy metal ions in groundwater, which varies by region based
on availability, level of industrialization, and level of environmental
responsibility. The concentration of fluoride anions in both surface water and
groundwater has been rising in various parts of the world because of discarded
effluents from semiconductors, electroplating, aluminum processing, the glass
and ceramic industries, beryllium extraction, power plants, and water