Innovations in Water Technologies:

The Impact of Graphene

As of June 2024, the National Institute of Statistics and Geography (INEGI) recorded that around 50% of Mexican territory was in severe drought, 30% in extreme drought, and 11% in exceptional drought, significantly impacting not only the supply of drinking water—only 52.3% of the population in Mexico has this service—but also numerous economic activities such as the agricultural and livestock sectors.

However, the water crisis is not a national issue alone. According to WHO/UNICEF, over 2000 million people worldwide lack access to potable water. These organizations have defined sustainable development goals for 2030 to ensure water availability, critical for improving hygiene education; protecting and restoring ecosystems; using water resources efficiently; investing in infrastructure and sanitation facilities; and promoting new water technologies, such as irrigation systems, rainwater collection, and treatment and reuse methods.

One such technology is nanotechnology, revolutionized 20 years ago by the isolation of graphene, a multifunctional carbon-based nanomaterial in the diamond and graphite family. Numerous studies have evaluated its effects on materials used in water technologies, such as filtration membranes and flocculants. Graphene’s extraordinary physicochemical characteristics, which can be controlled and shared with other three-dimensional materials, sparked interest. Initial studies as a nanofiller in primarily polymeric matrices revealed significant mechanical, antiadhesive, antifriction, antimicrobial, and filtering improvements. These enhancements increased its lifespan, reduced organic matter buildup on surfaces, and maintained consistent water flow and filtration efficiency.

For example, researchers from the Indian Institute of Technology Madras and Tel Aviv University in Israel successfully developed a silica aerogel with graphene oxide for wastewater decontamination. Meanwhile, scientists from Palacký University in Olomouc, Czech Republic, under the 2D-CHEM project funded by the European Research Council’s Graphene Flagship, designed acid graphene synthesized from fluorographene to remove heavy metals like lead and cadmium, as well as noble metals like palladium, gallium, and indium.

Notably, the promising research results on graphene in water technologies have moved from laboratories to the market. Companies exploiting its benefits include the Australian company CLEAN TEQ WATER, specializing in water treatment with presence in Melbourne, Beijing, Tianjin, and Africa. Its subsidiary NematiQ successfully developed graphene nanofiltration membranes that are more durable and energy-efficient, recently receiving the WaterMark certification as a safe product for water filtration. The British company EVOVE, formerly known as G2O Water Technologies, utilizes hydrophilic graphene oxide coatings to enhance the performance of conventional ceramic or polymeric membranes.

Finally, collaborative efforts between Graphene Flagship scientists and European leaders in water purification, such as Icon Lifesaver, Medica SpA, and Polymem S.A, through the GRAPHIL project, aim to introduce a new filtration system using hollow fiber polymer membranes mixed with graphene for safe potable water management, primarily for domestic use.

Graphene’s advancements are gradually gaining ground beyond academic borders to address one of the world’s most pressing issues. Energeia-Graphenemex®, a pioneering Mexican company in Latin America in the production and development of graphene materials applications, collaborates with other companies and research centers to find strategies to improve water availability and quality, aiming to bring new graphene applications to the market in the short term.

Author: EF/DHS

The Future of Batteries:

Graphene as a Sustainable Solution to the Lithium Crisis

In the last decade, the global increase in demand for lithium-ion batteries has been driven by the growing popularity of electronic devices, from portable devices such as tablets, consoles, and cell phones to electric vehicles. According to the International Monetary Fund, it is estimated that by 2050 the demand for batteries will exceed supply by 40%, posing a potential crisis for industries that depend on them if viable alternatives are not implemented.

The issues with lithium-ion batteries are not limited to supply-demand balance. Lithium is a finite resource whose extraction and disposal have negative impacts on the environment and human health. Additionally, batteries present significant safety risks such as instability, overcharging, overheating, and fires.

Graphene, a two-dimensional nanomaterial of carbon with an extremely thin, transparent, and strong sheet structure, has captured the attention of battery experts. Its unique architecture allows for high electrical conductivity and chemical stability, essential characteristics for improving the performance of lithium-ion batteries (LIB), lithium-sulfur batteries (LSB), and lithium-oxygen batteries (LOB).

Benefits of Graphene in Batteries:

1. Increased Energy Storage Capacity: Graphene has a structure with an extensive surface area, facilitating a greater number of intercalation sites for lithium ions. This translates into a significant improvement in the energy storage capacity of batteries.
2. Improved Electrical Conductivity: Graphene’s π-π bonds allow efficient electron transport between the active materials of the electrodes and the current collectors. This reduces the internal resistance of the batteries and improves their power output, which is crucial for applications requiring high charge and discharge rates.
3. Enhanced Stability and Durability: Graphene promotes the stability of electrode materials by preventing premature degradation during charge and discharge cycles. This not only extends the lifespan of batteries but also ensures greater cyclic stability, maintaining consistent performance over time.

Future Perspectives and Alternatives: Despite the continuous growth of the lithium-ion battery market, their environmental risks and technical limitations are driving research towards more sustainable and efficient alternatives. Some of these alternatives include sodium/sulfur-based battery systems, chitin/zinc, silicon/carbon, and combinations of graphene with other advanced materials.

At Energeia-Graphenemex, we are proud to be at the forefront of these innovations, exploring how graphene and other nanotechnological materials can continue transforming the battery industry and contributing to a cleaner and more sustainable energy future.

Writing: EF/ DHS

References:

1. A. Ali, P.K. Shen, Nonprecious metal’s graphene-supported electrocatalysts for hydrogen evolution reaction: fundamentals to applications, Carbon Energy 2 (2020) 99.
2. A. Ali, P.K. Shen, Recent progress in graphene-based nanostructured electrocatalysts for overall water splitting, Electrochem. Energy Rev. 3 (2020) 370;
3. A. Ali, P.K. Shen, Recent advances in graphene-based platinum and Palladium electrocatalysts for the methanol oxidation reaction, J. Mater. Chem. 7 (2019) 22189–22217; 4. Moreno-Brieva, Fernando, & Merino-Moreno, Carlos. (2020). Scientific and Technological Links from Samsung On Lithium Batteries and Graphene. Journal of technology management & innovation, 15(4), 81
4. Yu Yang, Renjie Wang, Zhaojie Shen, Quanqing Yu, Rui Xiong, Weixiang Shen, Towards a safer lithium-ion batteries: A critical review on cause, characteristics, warning and disposal  strategy for thermal runaway, Advances in Applied Energy, 11, 2023, 100146
5. https://www.hibridosyelectricos.com/coches/grafeno-baterias-coches-electricos_69751_102.html
6. https://rpp.pe/columnistas/fernandoortegasanmartin/grafeno-vs-litio-el-futuro-de-las-baterias-automotrices-noticia-1391824
7. https://www.energymonitor.ai/tech/energy-storage/graphene-is-set-to-disrupt-the-ev-battery-market/
8. https://www.eleconomista.com.mx/opinion/Datos-sobre-el-mercado-de-smartphones-en-Mexico-20240131-0117.html

Graphene as the Driver of the Energy Revolution:

Advances in Efficiency and Renewable Energy Storage

In today’s context, environmental concerns and climate change have shifted from being a trend to a top priority. This has led to the formation of multidisciplinary teams globally, focused on finding more sustainable technological solutions for energy challenges, such as energy generation and storage, with the additional aim of minimizing emissions.

In this context, thermal energy management through passive technologies, like solar energy, has gained significant importance. Its utilization as an eco-friendly and energetically efficient alternative has seen substantial growth, from its application in domestic settings to electricity generation systems.

However, the natural intermittence of solar energy due to diurnal and nocturnal cycles poses long-term challenges. Hence, it’s imperative to consider complementary technologies like Phase Change Materials (PCMs). These materials can absorb thermal energy from the surroundings to change their state, releasing stored energy for heating or cooling applications in various sectors, including construction, electronics, and aerospace.

Among the well-known PCMs is paraffin, which undergoes a solid-liquid phase change to store latent heat by absorbing thermal energy until reaching its melting point. While paraffins offer advantages such as being safe, reliable, economical, and having acceptable stability for long crystallization-fusion cycles, they also face challenges such as low thermal conductivity and leakage in the liquid state.

Fortunately, PCMs, including paraffin, benefit from advances in nanotechnology, especially when modified with nanoparticles like Graphene. Incorporating Graphene into PCMs like paraffin significantly enhances thermal conductivity and energy efficiency, facilitating solar-to-thermal energy conversion and storage.

What makes Graphene so special?

Graphene, with its exceptional physicochemical properties, is one of the most promising nanomaterials as a co-adjuvant in addressing energy-related challenges. Unlike other carbon nanostructures like diamond, graphite, activated carbon, fullerenes, or nanotubes, Graphene exhibits superior electrical and mechanical properties, with the added advantage of easy combination with other compounds like PCMs to share characteristics and enhance performance. For example, compared to nanotubes, one of the most well-known and studied carbon nanostructures, Graphene boasts higher charge mobility (200,000 cm2 V 1 s 1 Vs. 150,000 cm2 V 1 s 1), greater electrical conductivity (6.6 MS m -1 Vs. 0.35 MS m -1), and higher transmittance (97.0% Vs. 95.7%), making it highly attractive for energy-related applications.

How does Graphene relate to PCMs for solar energy utilization?

Historically, from a sustainable perspective and as a real-world application, architecture is a clear example of solar energy utilization. Starting from ancient times with the construction of adobe walls to trap daytime heat and release it at night, to modern infrastructure using heaters or solar panels, to Trombe walls as a passive heating tool. For instance, Trombe walls comprise materials like glass, wood, steel, aluminum, concrete, and PCMs like paraffin, arranged in special configurations that collectively absorb heat to slowly conduct it into the dwelling.

Through the identification of Graphene’s multifunctional properties and the exploration of its benefits in various sectors, it was found that its integration into paraffin used for passive heating systems can significantly improve thermal conductivity or driving force by up to 164%, showcasing clear superiority over highly efficient hybrid nanoparticles like Cu-TiO2 or Al2O3-MWCNT, whose normal benefits range between 50 and 70%. This means that integrating these technologies into passive heating systems, besides improving thermal comfort throughout the year, would also yield significant energy savings and reduce CO2 emissions.

Solar cells

Another well-known potential application of nanotechnology in the energy sector is the design of the fourth generation of solar panels, which includes the use of two-dimensional nanomaterials like molybdenum disulfide (MoS2), tungsten diselenide (WSe2), and again, Graphene.

Among the most representative advantages that Graphene has demonstrated over other materials are, in addition to its mechanical strength, its high charge mobility, great transmittance, lightness, flexibility, and stability, which have led to significant advances in its performance for solar panel design, increasing its efficiency from 1.5% to 15% in less than 10 years, almost comparable to the efficiency of current cells ranging from 20 to 22%. However, in pursuit of further improving these percentages, experts in the field continue to explore methodologies based on Graphene doping with other structures like silicon, molybdenum hexafluoride, molybdenum oxide, thionyl chloride, trioxionitric acid, gold chloride, boron, oxygen, nitrogen, phosphorus, or sulfur, to reduce its resistance and better harness solar energy.

At Energeia-Graphenemex, the leading company in Latin America in the design and development of graphene-based applications, we are aware of the challenges that Graphene, like any emerging technology, faces, and we are pleased to be part of the select group of researchers and industrialists globally seeking to benefit society, the economy, and the environment with the advantages these wonderful materials can offer.

Thanks to our multidisciplinary team, we have quickly overcome the obstacles that have hindered the arrival of this material to the market in real applications, starting with its large-scale production, with controlled quality and at an affordable cost, as well as with the development of new products with graphene nanoengineering, where controlling its stability and compatibility with compounds and processes used in each application or industry has been fundamental.

Graphene as an ally of renewable energies is still in its early stages, not necessarily due to its manipulation but because of the complexity this sector represents. However, the significant advances made over the past decade should not be underestimated, as they lay the groundwork for the next generations of equipment and technologies.

Redaction: EF/DHS

References

1. Jafaryar M, Sheikholeslami M. Simulation of melting paraffin with graphene nanoparticles within a solar thermal energy storage system. Sci Rep. 2023, 26;13(1):8604;
2. R. Bharathiraja, T. Ramkumar, M. Selvakumar. Studies on the thermal characteristics of nano-enhanced paraffin wax phase change material (PCM) for thermal storage applications. J. Energy Storage, 73, Part C, 2023, 109216;
3. Li-Wu Fan, Xin Fang, Xiao Wang, Yi Zeng, Yu-Qi Xiao, Zi-Tao Yu, Xu Xu, Ya-Cai Hu, Ke-Fa Cen, Effects of various carbon nanofillers on the thermal conductivity and energy storage properties of paraffin-based nanocomposite phase change materials, Applied Energy, 110, 2013, 163;
4. Top Khac Le., et al., Advances in solar energy harvesting integrated by van der Waals graphene heterojunctions. RSC Adv., 2023, 13, 31273