New research explores durability of 2D semiconductors
Texas A&M team show that that 2D hybrid organic-inorganic perovskites can survive over one billion cycles
New research has unveiled the fatigue resistance of 2D hybrid organic-inorganic perovskites (HOIPs) semiconductors .
Led by Qing Tu, professor in the Department of Materials Science and Engineering at Texas A&M University, this is the first study of fatigue behaviour of HOIPs in practical applications. The researchers published their findings in Advanced Sciences.
This new generation of semiconductors holds great potential in nearly the whole spectra of semiconductor applications, including photovoltaics, light-emitting diodes and photosensors, among others. The application of repeated or fluctuating stresses below the material’s strength, known as fatigue loading, often leads to failure in 2D hybrid materials. However, the fatigue properties of these materials have remained elusive despite their widespread use in various applications.
The research group demonstrated how fatigue loading conditions, wearing different components, would affect the lifetime and failure behaviour of the new materials. Their results provide insights into designing and engineering 2D HOIPs and other hybrid organic-inorganic materials for long-term mechanical durability.
Researchers discovered that 2D HOIPs can survive over one billion cycles, much longer than engineering practical application needs (typically on the order of 105 to 106 cycles), which outperforms most polymers under similar loading conditions and suggests that 2D HOIPs are fatigue robust. Tu said further examining the failure morphology of the materials reveals both brittle (similar to other 3D oxide perovskites owing to the ionic bonding in the crystals) and ductile (similar to organic materials like polymer) behaviors depending on the loading conditions.
The recurrent component of the loading conditions can significantly drive the creation and accumulation of defects in these materials, which ultimately leads to mechanical failure. The unexpected plastic deformation, suggested by the ductile behaviour, is likely to impede the mechanical failure and be the cause of the long fatigue lifetime. This special failure behaviour under cyclic stress is probably due to the hybrid organic-inorganic bonding nature, unlike most conventional materials, which typically exhibit pure inorganic or pure organic bonding.
The team also investigated how each component of the stress and the materials’ thickness affect fatigue behaviour.
“My group has been continuing working on understanding how the chemistry and environmental stressors, such as temperature, humidity and light illumination, affect the mechanical property for this new family of semiconductor material,” Tu said.
The work at Texas A&M is partially supported by the Haythornthwaite Research Initiation Award that Tu received in 2021 from the American Society of Mechanical Engineers – Applied Mechanics Division and by a recent grant from the National Science Foundation.
Reference
'Unveiling the Fatigue Behavior of 2D Hybrid Organic–Inorganic Perovskites: Insights for Long-Term Durability' by Doyun Kim et al ; Advanced Science (July 2023)
