DiamNex turns diamond flexible in push for cooling tech

The startup is building a factory in China to supply samples to potential partners.

DiamNex Ltd. is seeking to turn diamond into a flexible cooling technology, betting that wafer-thin films can manage heat where existing materials fall short.

The Hong Kong startup is commercialising a patented process that grows diamond as micrometre-thick films, thin enough to bend without cracking whilst keeping diamond’s thermal and optical performance. The approach aims to overcome the brittleness and cost that have long limited diamond’s wider use in manufacturing.

“Once diamond is thin enough, it is no longer brittle in the way people traditionally think of it,” Zhiqin Chu, director at the HKU Diamond Laboratory and DiamNex’s founder and chief scientist, told Hong Kong Business.

DiamNex was set up last year to prove the concept could work at industrial consistency, not just in the lab. Instead of changing how diamond is used, the company altered its physical form, allowing it to fit applications where rigid diamond fails.

The startup is building a small production line in Shenzhen,China to supply samples to potential partners.

“At this stage, consistency matters more than scale,” Chu said via Zoom. The company plans to assess its readiness to scale by midyear after gathering customer feedback.

Its first target market is thermal heat spreaders for electric vehicles, power electronics and communication equipment, where overheating limits performance. Optical windows and specialised coatings are secondary targets, whilst diamond-based semiconductors remain longer term.

Energy costs remain a constraint. Diamond growth through chemical vapour deposition is power-intensive, shaping decisions on where production can expand.

For now, DiamNex is prioritising validation: showing that flexible diamond films can be produced reliably and integrated into real systems. Scaling, licensing or partnerships will follow once customers confirm the material delivers under real-world conditions.