A Delicate Balance between Antiferromagnetism and Ferromagnetism: Theoretical and Experimental Studies of A MRu B (A=Zr, Hf; M=Fe, Mn) Metal Borides.

Metal-rich borides with the Ti Co B -type structure represent an ideal playground for tuning magnetic interactions through chemical substitutions. In this work, density functional theory (DFT) and experimental studies of Ru-rich quaternary borides with the general composition A MRu B (A=Zr, Hf, M=Fe, Mn) are presented. Total energy calculations show that the phases Zr FeRu B and Hf FeRu B prefer ground states with strong antiferromagnetic (AFM) interactions between ferromagnetic (FM) M-chains.

Covalent Atomic Bridges Enable Unidirectional Enhancement of Electronic Transport in Aligned Carbon Nanotubes.

Interconnecting the surfaces of nanomaterials without compromising their outstanding mechanical, thermal, and electronic properties is critical in the design of advanced bulk structures that still preserve the novel properties of their nanoscale constituents. As such, bridging the π-conjugated carbon surfaces of single-walled carbon nanotubes (SWNTs) has special implications in next-generation electronics. This study presents a rational path toward the improvement of the electrical transport in aligned semiconducting SWNT films by deposition of metal atoms.

MoS-Based Optoelectronic Gas Sensor with Sub-parts-per-billion Limit of NO Gas Detection.

Red light illumination with photon energy matching the direct band gap of chemical vapor deposition grown single-layer MoS with Au metal electrodes was used to induce a photocurrent which was employed instead of dark current for NO gas sensing. The resulting Au/MoS/Au optoelectronic gas sensor showed a significant enhancement of the device sensitivity S toward ppb level of NO gas exposure reaching S = 4.9%/ppb (4900%/ppm), where S is a slope of dependence of relative change of the sensor resistance on NO concentration.

Effect of Substitution on the Hysteretic Phase Transition in a Bistable Phenalenyl-Based Neutral Radical Molecular Conductor.

The ability to tune the physical properties of bistable organic functional materials by means of chemistry can facilitate their development for molecular electronic switching components. The butylamine-containing biphenalenyl boron neutral radical, [Bu] B, crystalline compound has recently attracted significant attention by displaying a hysteretic phase transition accompanied by simultaneous bistability in magnetic, electrical, and optical properties close to room temperature. In this report, substitutional doping was applied to [Bu] B by crystallizing solid solutions of bistable [Bu] B and its non-radical-containing counterpart [Bu] Be.

Phenalenyl based neutral radical as a novel electrochromic material modulating visible to short-wave infrared light.

Applications for energy saving smart windows require materials which can switch from transmissive to black states in both the visible and short-wave IR range. We introduce an electrochromic phenalenyl based neutral radical small molecule and design devices capable of modulating light in both of these ranges.