Researchers from the National University of Singapore (NUS) have introduced a groundbreaking advancement in the form of an ultra-thin carbon membrane that could significantly enhance the precision of proton therapy for cancer treatment. This innovation is expected to not only benefit the medical field but also to have applications in energy devices and flexible electronics.

Introducing Ultra-Clean Monolayer Amorphous Carbon (UC-MAC)

The newly developed material, termed ultra-clean monolayer amorphous carbon (UC-MAC), is exceptionally promising. At a thickness of merely one atom, it has demonstrated the potential to generate high-precision proton beams that drastically improve the effectiveness of proton therapy, a non-invasive cancer treatment method.

This research is published in Nature Nanotechnology and is spearheaded by Associate Professor Lu Jiong and his dedicated team from the NUS Department of Chemistry, collaborating with international experts.

A Novel Carbon Structure

UC-MAC distinguishes itself from graphene, a well-known carbon allotrope characterized by a honeycomb structure of ordered hexagonal rings. Instead, UC-MAC presents a complex arrangement incorporating five-, six-, and seven-membered carbon rings, leading to a disordered yet functional ultra-thin sheet. This atomic-level disorder is beneficial as it creates angstrom-scale pores, measuring just one ten-billionth of a meter wide.

The design of these pores allows precise control over the behavior of particles, such as protons and molecular hydrogen ions (H2+). As a result, UC-MAC significantly enhances the capability to filter and manipulate subatomic particles, fulfilling a critical need in high-tech applications.

Advancements in Manufacturing Protocols

A major challenge in utilizing UC-MAC for practical applications is the current limitations of its manufacturing processes, which are often slow, expensive, and introduce metal impurities. To address this, researchers have developed an industry-compatible synthesis process known as the disorder-to-disorder (DTD) approach. This innovative method employs plasma-enhanced chemical vapor deposition (PECVD), allowing for the rapid growth of an 8-inch UC-MAC sheet in seconds without detectable metal contamination.

Process Benefits
Disorder-to-Disorder Synthesis Fast production of UC-MAC sheets without metal impurities.
Industry-Compatible Facilitates scaling up for broader industrial and medical uses.

Enhanced Proton Beam Performance

When applied as a membrane to separate molecular hydrogen ions (H2+) into individual protons, UC-MAC has produced markedly sharper proton beams compared to those generated via graphene or traditional carbon films. Specifically, UC-MAC has shown to reduce unwanted proton scattering events by:

  • Twice as much as graphene.
  • 40 times more than commercial carbon thin films.

This characteristic is particularly important in proton therapy, where controlled and focused beams are essential to target and destroy cancerous tumors while sparing healthy surrounding tissues.

Looking Beyond Medicine

The capabilities of UC-MAC extend far beyond proton therapy. The material's ultra-clean and porous structure lends itself well to various applications, including:

Application Potential Impacts
Energy Devices Enhanced fuel cells and battery performance.
Catalysis Improved molecular separation processes.
Flexible Electronics Ultra-thin electronics for sub-2 nm integrated circuits.

Professor Lu highlights that the semiconducting properties of UC-MAC films position them as promising candidates for ultra-thin electronics, tackling critical challenges in the rapidly evolving world of technology.

Conclusion

Through collaborative efforts, the research team has successfully demonstrated a clean, efficient, and scalable method for producing UC-MAC. This material not only represents a significant advancement in proton beam technology but also opens doors to innovative applications in various fields. The potential transition of UC-MAC from laboratory research to real-world applications marks a promising leap towards enhancing the safety and efficacy of cancer treatments and beyond.

For more information, refer to the original publication: Huihui Lin et al., "Ultraclean monolayer amorphous carbon yields a high-precision proton beam," Nature Nanotechnology (2025). DOI: 10.1038/s41565-025-01968-3.

References

[1] Lin, H. et al. "Ultraclean monolayer amorphous carbon yields a high-precision proton beam." Nature Nanotechnology, 2025.

[2] National University of Singapore. "Ultra-thin carbon membrane sharpens proton beams, potentially boosting cancer treatment precision." Retrieved from Phys.org.