Synergetic Effect of Metal Nanoparticle Embedded Graphene Membrane : A Novel Approach for Antimicrobial Filtration

Title

Synergetic Effect of Metal Nanoparticle Embedded Graphene Membrane : A Novel Approach for Antimicrobial Filtration

Creator

Jephin, K Jose

Contributor

B, Manoj and Cherian, Christie Thomas

Description

Water, the elixir of life, holds a profound significance that extends far beyond its essential utility. It's not just a resource; it pulsates as the life force of our existence, intricately woven into the very fabric of our daily lives. Water is the silent force that shapes our world, from nurturing our health and sustaining social structures to fueling economic development and fostering the environment. However, the adequacy of potable water quality confronts adverse impacts stemming from inadequate wastewater treatment, escalating domestic and industrial waste, and the microbial contamination of surface water sources. Furthermore, climate change emerges as a pivotal factor intensifying the depletion of water levels in natural resources due to diminished rainfall. Reports project that, by 2025, two-thirds of global population might contend with water scarcity. Given the persistence of current scenario, there exists a notable potential for significant conflicts among nations stemming from water scarcity. However, such a predicament can be mitigated through proactive measures, including the preservation of natural resources and the implementation of advanced technologies to recover fresh water from contaminated sources. Advanced technologies for the purification of contaminated water encompass sedimentation, precipitation, filtration, and ion exchange, which can effectively extract clean water from diverse impurities. Notably, membrane-based purification has gained prominence in recent years, owing to its cost- effectiveness and energy-saving attributes. Carbon-based nanomaterials, including carbon nanotubes,fullerenes and graphene have garnered considerable attention in recent research studies, particularly in the realm of membrane applications. Within this, membranes fabricated by carbon nanotubes (CNT) stand out, showcasing exceptional filtering properties attributed to their tubular carbon structure. However, the cost-effectiveness and ease of synthesis impediments pose significant challenges, acting as bottlenecks for their widespread application in water purification. Consequently, graphene-based membranes emerge as a promising alternative to CNT membranes, demonstrating selective separation of ions and molecules. Specifically, membranes derived from graphene oxide (GO) and reduced graphene oxide (rGO) exhibit superior filtering capabilities compared to ceramic and polymeric counterparts, owing to their layered structure featuring tunable nanochannels, hydrophilic or hydrophobic nature, and commendable mechanical resilience. Graphene oxide solution synthesis has been done using Hummer's method, followed by fabrication of high-quality membranes through vacuum filtration techniques. Current work emphasis on recognizing the pivotal influence of membrane thickness on both water flux and dye rejection, meticulous optimization of filtration properties by producing graphene oxide (GO) membranes at various concentrations. Furthermore, reduction of graphene oxide through the hydrothermal method, enabling a comprehensive comparative analysis of water flux and rejection between graphene oxide (GO) and reduced graphene oxide (rGO) membranes was carried out. In our investigation, the results unequivocally validate that the GO 500 sample exhibits optimized filtration properties. Furthermore, the reduced graphene oxide (rGO) variant surpasses graphene oxide (GO) in terms of filtration efficacy, demonstrating superior filtering properties. It is noteworthy to highlight that reduced graphene oxide (rGO) exhibits less antibacterial properties compared to graphene oxide (GO). The disinfection capability of the membrane is pivotal in ensuring the recovery of pure water. To bolster the antibacterial features of GO, we have undertaken an enhancement strategy by incorporating silver nanoparticles. Silver nanoparticle, showcases multifaceted properties including surface plasmon resonance and unique morphologies, which contribute significantly to the inactivation of bacteria. The conducted studies reveal that membranes incorporating graphene oxide with silver (GO-Ag) exhibit remarkable antibacterial properties against both gram-positive and gram-negative bacteria. Additionally, these membranes demonstrate appreciable filtration capabilities and exhibit effective antifouling properties, further emphasizing their potential for advanced applications in water purification systems. Fouling is a significant challenge in membrane technology, as the continuous passage of contaminants results in the formation of layers on membrane surface, thereby diminishing its filtration efficiency. Despite the antifouling properties exhibited by GO- Ag membranes, there exists further improvement in enhancing performance and extending the membrane's lifespan. To address this, we have undertaken a reduction of graphene oxide and incorporated silver nanoparticles, aiming to augment the antifouling properties and overall efficacy of membrane. The conclusive findings indicate that fine-tuned membrane exhibits remarkable antibacterial properties, superior filtration capabilities, and a minimal irreversible fouling ratio. These outcomes provide confirmation that the fabricated membranes stand as potential materials for water purification applications, showcasing a well-rounded set of properties essential for effective and sustainable water treatment.

Source

Author's Submission

Date

2024-01-01

Publisher

Christ(Deemed to be University)

Subject

Physics and Electronics

Rights

Open Access

Relation

61000332

Format

PDF

Language

English

Type

PhD

Identifier

http://hdl.handle.net/10603/574359