New research demonstrates G3 graphene’s potential in solar-driven water treatment
New research using Levidian’s G3 graphene has been published in Advanced Science, demonstrating how small additions of graphene can support stable solar-driven evaporation under highly concentrated brine conditions.
Led by researchers at the University of Birmingham, the study investigated graphene-enhanced porous evaporators designed for solar-driven interfacial evaporation, a process that uses sunlight to heat and evaporate water at the surface of a material.
The technology has potential applications in desalination and industrial water treatment, particularly in regions where access to solar energy is high and the management of concentrated brine remains a significant technical challenge.
High performance at low graphene loading
A key finding from the study was that increasing the amount of graphene did not necessarily result in better overall performance.
The best-performing structure contained just 0.5 wt.% Levidian G3 graphene nanoplatelets. Under testing in a 20 wt.% sodium chloride solution, approximately six times the salinity of seawater, and the material retained more than 90% of its peak evaporation flux after four hours.
The findings highlight the importance of optimising graphene as part of the complete material system, rather than simply increasing the concentration of photothermal material.
Professor Ali Sadaghiani, who led the research at the University of Birmingham, said:
“Graphene has significant potential in solar-driven water treatment because strong photothermal functionality can be introduced with relatively small material additions. What our work with G3 shows, however, is that the next step is not simply to increase photothermal material loading, but to integrate it with the 3D transport architecture of the system.
“In our study, only 0.5 wt.% G3 was sufficient to achieve strong photothermal performance while retaining more than 90% of the peak evaporation flux under highly concentrated brine. Going forward, I see materials such as G3 becoming part of a broader design strategy in which photothermal conversion, water supply, salt redistribution and vapour transport are engineered together to enable more stable solar-driven water treatment.”
Designing for sustained performance
One of the most significant conclusions from the research is that the hottest, or initially fastest, evaporator is not necessarily the most effective over longer periods.
As water evaporates from concentrated brine, salt can accumulate within the material and interfere with water transport and evaporation. The design therefore has to balance several processes simultaneously, including heat generation, capillary water supply, salt redistribution, and the removal of water vapour.
This means that successful solar-driven evaporation depends not only on the photothermal properties of graphene, but also on how those properties interact with the physical architecture of the evaporator.
For graphene applications more broadly, the finding reinforces an increasingly important principle: more graphene does not automatically mean better performance. The material must be matched to the formulation, structure, and requirements of the final application.
Dr Arun Prakash Aranga Raju, Technical Lead, Graphene Commercialisation (MENA) at Levidian and co-author of the paper, said:
“Small amounts of graphene, when well matched to the device design, can outperform higher loadings. Using less material per device improves material efficiency and helps keep solar-driven water treatment cost-effective at scale.”
Potential for desalination and industrial water treatment
Solar-driven interfacial evaporation is particularly relevant to regions with high levels of solar availability and significant demand for desalination, including the Middle East and North Africa.
While desalination plays an important role in water security across the region, the management of highly concentrated brine streams remains an ongoing technical challenge.
Materials capable of supporting efficient evaporation while maintaining stable performance under high-salinity conditions could therefore contribute to the development of new approaches to water treatment and brine management.
The research also demonstrates the wider opportunity for graphene to deliver meaningful improvements at relatively low concentrations, where the focus is not simply on adding an advanced material but on engineering it effectively into the wider system.
The study was supported by the European Research Council, with additional contributions from the Manufacturing Technology Centre.
Congratulations to Professor Ali Sadaghiani, the University of Birmingham research team, and all collaborators involved in the study.
Read the full research paper in Advanced Science: https://advanced.onlinelibrary.wiley.com/doi/10.1002/advs.77527
