Diamond has long been treated as one of the most electrically inactive materials in engineering. Now, researchers have found that when diamond is made thin enough to bend, it can produce measurable electrical signals, overturning a scientific assumption that has lasted for more than a century.
• Ultrathin diamond membranes produced measurable voltage
• The discovery challenges a long-standing scientific belief
• Mechanical bending appears to trigger the electrical effect
Researchers at the University of Hong Kong created extremely thin, flexible membranes from polycrystalline diamond. Unlike ordinary diamond, which is exceptionally rigid, these membranes can bend under mechanical stress. When the team repeatedly flexed them, stable voltage signals appeared, suggesting the diamond itself was generating electricity.
• Scientists produced flexible diamond membranes
• Bending the material repeatedly generated voltage
• Tests were designed to rule out false electrical signals
The researchers investigated the phenomenon further to determine where the electricity was coming from. Their calculations point to tiny boundaries between individual diamond crystals inside the membrane. When the material bends, these grain boundaries develop an uneven distribution of electrical charge, creating a voltage difference between the membrane’s surfaces.
• Grain boundaries appear to drive the effect
• Bending causes electrical polarization inside the material
• The voltage can be produced repeatedly
The finding could give diamond an entirely new role in technology. Its extreme durability, chemical stability and biocompatibility already make it valuable in demanding environments. A flexible diamond material that can convert mechanical movement into electricity could eventually become useful for sensors, tiny power systems and certain implantable medical devices.
• Diamond could become an active electrical material
• Potential applications include sensors and medical devices
• Self-powered miniature systems could benefit from the discovery
For more than a century, diamond’s reputation was built around what it could withstand rather than what it could generate. The HKU research suggests that changing the material’s structure and scale can reveal properties hidden in bulk diamond. That could turn one of the world’s hardest materials into a surprisingly useful source of electrical signals.
Via: Science Daily
