Showing Spotlights 65 - 72 of 328 in category All (newest first):
In order to exploit the remarkable mechanical properties of graphene for practical applications, nanoscale graphene sheets need to be assembled into much larger, macroscopic structures. However, there are two pivotal issues that make this task challenging: One is the inherently misaligned and wrinkled structure of graphene platelets; another is the weak interfacial interaction among graphene platelets. Both these problems greatly degrade the properties of macroscopic graphene assemblies such as sheets and fibers.
Feb 10th, 2021
The industrial production of ammonia mostly relies on the energy-intensive Haber-Bosch process, which causes significant environmental pollution. Researchers have now proposed that a class of 2D transition metal borides termed MBenes - the boron-analogues of MXenes - could be used as catalyst for ammonia production through electrochemical nitrogen reduction reaction (NRR). This work also provides a general design principle for further exploration of an even broader composition space of MBenes and other 2D NRR electrocatalysts.
Nov 17th, 2020
The use of graphene-based materials in pharmaceutical nanotechnology has recently received more attention due to their unique chemical structure and physicochemical properties - including an ultra-high surface area, optical, thermal and electrical conductivities, and a good biocompatibility. They can also load large amounts of drug molecules on both sides of the single atom layer sheet. The next generation of cancer nanotheranostics employing graphene-based nanomaterials could address the many challenges associated with traditional chemotherapeutic agents, such as the issues surrounding poor solubility, harmful side effects, non-specific drug distribution, and multi-drug resistance.
Oct 9th, 2020
Researchers demonstrate that single-grain growth of graphene crystals can be achieved over a large, macroscale, area. Specifically, the team shows that graphene flakes, nucleated over a polycrystalline graphene film, synchronize during growth so as to ultimately yield a common crystal orientation at the macroscale. The phenomenon of self-alignment of graphene grains during their growth, which the team discovered experimentally, has never been observed before - and at this time the scientists don't have a good model for the underlying physics which leads to this effect.
Sep 30th, 2020
Any working electronic device is the source of electromagnetic (EM) radiation. Device miniaturization and a consequent increase in the heat and electromagnetic (EM) wave emission in the electronic systems make the simultaneous heat management and electromagnetic interference (EMI) shielding crucially important. New research shows that the extremely high thermal conductivity of graphene and good electrical conductivity, even without the energy band-gap, make graphene promising for EMI shielding and thermal management applications.
Sep 28th, 2020
Researchers have provided an example of on-demand control of quantum phenomena to design the quantum materials. By state-of-the-art quantum mechanical simulations, they find that a two-dimensional transition-metal ditelluride, MoTe2, can realize a structural phase transition from the semiconducting phase to the topological phase triggered by photoexcitation of carriers alone. The sub-picosecond phase transition can be controlled by varying the laser wavelength. The research is inspired by the classical phase transition theory proposed by Lev Davidovich Landau and Rudolf Ernst Peierls.
Sep 14th, 2020
Periodically strained graphene harbors correlated electronic phases similar to those previously observed in magic angle twisted bilayer graphene. By precisely rotating two stacked sheets of graphene one can induce superconducting and insulating phases depending on the electric density. This behavior is extremely desirable because it significantly reduces energy losses in electronic devices making them more efficient and durable. Researchers have now proposed an alternative way to obtain similar phases. Their approach relies on periodically straining a graphene sheet rather than stacking layers on top of each other.
Aug 13th, 2020
Charge density wave (CDW) is a quantum mechanical phenomenon, which induces distortion in the crystal structures of some low-dimensional (1D or 2D) metals, when the temperature is reduced. Such distorted crystal structure is known as CDW phase and its resistivity is much higher than the original symmetric phase. Since the switching between symmetric and CDW phase can also be made by the application of external electric field, these materials are technologically important and have attracted immense attention in the nanoelectronics community.
Aug 6th, 2020