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An efficient, green, and sustainable synthesis of new hybrid molecules containing flavanone with triazole by merging the Michael addition and Click reaction using a copper oxide/reduced graphene oxide nanocomposite in one pot is reported. The catalyst can easily be recycled and reused in seven consecutive runs without compromising the product yields. Other notable advantages include using water as a reaction medium and obtaining good to excellent yields, low catalyst loading, high atom efficiency, high substrate variation, and good results in the gram scale reaction., Competing Interests: The authors declare no competing financial interest.

We report comparative field electron emission (FE) studies on a large-area array of two-dimensional MoS 2 -coated @ one-dimensional (1D) brookite (β) TiO 2 nanorods synthesized on Si substrate utilizing hot-filament metal vapor deposition technique and pulsed laser deposition method, independently. The 10 nm wide and 760 nm long 1D β-TiO 2 nanorods were coated with MoS 2 layers of thickness ∼4 (±2), 20 (±3), and 40 (±3) nm. The turn-on field ( E on ) of 2.5 V/μm required to a draw current density of 10 μA/cm 2 observed for MoS 2 -coated 1D β-TiO 2 nanorods emitters is significantly lower than that of doped/undoped 1D TiO 2 nanostructures, pristine MoS 2 sheets, MoS 2 @SnO 2 , and TiO 2 @MoS 2 heterostructure-based field emitters. The orthodoxy test confirms the viability of the field emission measurements, specifically field enhancement factor (β FE ) of the MoS 2 @TiO 2 /Si emitters. The enhanced FE behavior of the MoS 2 @TiO 2 /Si emitter can be attributed to the modulation of the electronic properties due to heterostructure and interface effects, in addition to the high aspect ratio of the vertically aligned TiO 2 nanorods. Furthermore, these MoS 2 @TiO 2 /Si emitters exhibit better emission stability. The results obtained herein suggest that the heteroarchitecture of MoS 2 @β-TiO 2 nanorods holds the potential for their applications in FE-based nanoelectronic devices such as displays and electron sources. Moreover, the strategy employed here to enhance the FE behavior via rational design of heteroarchitecture structure can be further extended to improve other functionalities of various nanomaterials., Competing Interests: The authors declare no competing financial interest.

In many biomedical applications, broad full-color emission is important, especially for wavelengths below 450 nm, which are difficult to cover via supercontinuum generation. Single-crystalline-core sapphires with defect-driven emissions have potential roles in the development of next-generation broadband light sources because their defect centers demonstrate multiple emission bands with tailored ligand fields. However, the inability to realize high quantum yields with high crystallinity by conventional methods hinders the applicability of ultra-broadband emissions. Here, we present how an effective one-step fiber-drawing process, followed by a simple and controllable thermal treatment, enables a low-loss, full-color, and crystal fiber-based generation with substantial color variability. The broad spectrum extends from 330 nm, which is over 50 nm further into the UV region than that in previously reported results. The predicted submicrometer spatial resolutions demonstrate that the defect-ligand fields are potentially beneficial for achieving in vivo cellular tomography. It is also noteworthy that the efficiency of the milliwatt-level full-color generation, with an optical-to-optical efficiency of nearly 5%, is the highest among that of the existing active waveguide schemes. In addition, direct evidence from high-resolution transmission electron microscopy together with electron energy loss spectroscopy and crystal-field ligands reveals an excellent crystalline core, atomically defined core/cladding interfacial roughness, and significant enhancements in new laser-induced electronic defect levels. Our work suggests an inexpensive, facile, and highly scalable route toward achieving cellular-resolution tomographic imaging and represents an important step in the development of endoscope-compatible diagnostic devices., Competing Interests: The authors declare no competing financial interest.