Plasma treatment of some inorganic nano-materials has shown the way towards bright, stable and affordable light-emitting diodes (LEDs).

Cost-efficient and bright light-emitting diodes (LEDs) are in demand, but attaining the desired stability and brightness have been challenges. Scientists are looking for new materials that are stable, produce bright emissions and can be commercially viable.

Researchers at the Centre for Nano and Soft Matter Sciences (CeNS) have found that simple plasma treatment of inorganic material cesium lead halide nanocrystals can lead to enhanced stabilisation.

The researchers, led by Dr Pralay K Santra, found that a mechanism of plasma treatment induced stability enhancement in inorganic perovskite nanocrystals, which could boost their emission. Plasma treatment induces cross-linking of the organic molecules oleylamine present on the surface of the nanocrystals. This creates a stronger network of ligands, providing better encapsulation and higher photoluminescence intensity.

Methanol as carbon sink

The global methanol market is projected to reach $26 billion by 2025, with a compound annual growth rate of 6.6 per cent from 2019 to 2025. Traditionally, methanol has been produced from fossil fuels such as natural gas and coal. However, methanol production from captured carbon dioxide is an emerging sustainable route, according to Noor Yusuf and Fares Almomani of Qatar University.

The hydrogenation of carbon dioxide to methanol is one of the promising carbon dioxide utilisation routes in the industry that can contribute to emission mitigation. In a paper published in the upcoming issue of Fuel journal, they report “sustainable catalytic hydrogenation of carbon dioxide to methanol using copper or zinc oxide or aluminium oxide catalyst operated at 70 bar and 210 degrees C.”

The pure carbon dioxide feedstock used for this process is produced from the cryogenic upgrading process of biogas or hydrocarbon industries and ready-to-use hydrogen purchased at 30 bar and 25 degrees C. “The proposed methanol process with an annual production rate of 2.34 kt is economically sound with a payback period of nine years if the maximum hydrogen price remains below $0.97 per kg. Hence, producing or purchasing grey hydrogen from a steam reforming plant is most viable,” the authors say.

Rapid test for sickle cell anaemia

Researchers led by Sai Siva Gorthi in the Department of Instrumentation and Applied Physics at the Indian Institute of Science, Bengaluru, and collaborators have designed a rapid, low-cost, point-of-care method to detect sickle cell anaemia, says IISc newsletter Kernel. Sickle cell anaemia is a killer disease, which occurs due to a genetic mutation that causes haemoglobin in red blood cells to clump together.

The system designed at IISc relies on the property of haemoglobin in a solution to absorb and transmit light. The team observed differences in the light absorption between deoxygenated blood samples from sick and healthy volunteers. In preliminary clinical trials with 438 samples, the test showed high sensitivity (96.9 per cent) and specificity (98.6 per cent). The test takes only 15 minutes and may cost less than ₹100. A patent has been filed and licensed by ShanMukha Innovations, an IISc-incubated startup, says Kernel.