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Blue-emitting OLED devices structured using star-shaped truxene-based discotic liquid crystals.

Star-shaped Blue Emitting Truxene-based Discotic Liquid Crystalline Molecules: Synthesis, Self-assembly, and Electroluminescence Studies
Shallu Dhingra, Feng-Rong Chen, Iram Siddiqui, Santosh Prasad Gupta, Jwo-Huei Jou, and Santanu Kumar Pal

Prayogic Rasayan 2023, 7(3), 66-74

DOI: https://www.doi.org/10.53023/p.rasayan-20230608

Keywords: Discotic liquid crystal, truxene, columnar hexagonal mesophase, blue emitter, OLED, EQE

Two new C3 symmetrical star-shaped truxene-based discotic liquid crystals have been designed to study their optoelectronic properties. Both the truxene derivatives exhibited columnar hexagonal self-assembly, confirmed by a thorough analysis using POM, DSC, and XRD. A multilayered OLED device was structured using these mesogens as blue emitters for electroluminescent studies. The best-performing configuration was perceived for devices based on emitter 1b at a dopant concentration of 1 wt% in a well-aligned CBP host, giving a maximum EQE of 2.9%.

Green Synthesis, Functionalization and catalytic Activity of Palladium nanoparticles for development of Eco-friendly methods
Chhabi Garai

Prayogic Rasayan 2023, 7(3), 75-83

DOI: https://doi.org/10.53023/p.rasayan-20230719

Keywords: Palladium nanoparticle, green synthesis, functionalization, C-C coupling, Dye degradation

During the past few decades metal nanoparticles are in the forefront of research for their unique properties and wide range of versatile applications. Among the several transitional metal nanoparticles palladium nanoparticles (PdNPs) are most interesting for their superior catalytic activity towards several organic reactions and also used as recyclable catalyst. Now being the time when environmental issue is a great concern and needs development of environmentally benign process. Synthesis of PdNPs using non-toxic chemicals and solvents, mild reaction condition, bio-degradable reducing or stabilizing agent, alternative energy sources are energy efficient and also cost effective and considered as green process Functionalization on the surface of PdNPs, nanoparticles showed excellent catalytic activity and can perform organic reactions in eco-friendly conditions. In this review different green synthetic methods, surface functionalization and catalytic activity of PdNPs towards several C-C coupling reactions, toxic dye degradations are discussed.