Efficient cooling of silicon chips using microfin structures made of aligned multiwalled carbon nanotube arrays is achieved. The tiny cooling elements mounted on the back side of the chips enable power dissipation from the heated chips on the level of modern electronics demands. The nanotube fins are mechanically superior compared to other materials being ten times lighter, flexible, and stiff at the same time. These properties accompanied with the relative simplicity of the fabrication makes the nanotube structures strong candidates for future on-chip thermal management applications.

Transition metal dichalcogenides (TMDs) have received immense research interest in particular for their outstanding electrochemical and optoelectrical properties. Lately, chemical gas sensor applications of TMDs have been recognized as well owing to the low operating temperatures of devices, which is a great advantage over conventional metal oxide based sensors. In this work, we elaborate on the gas sensing properties of WS₂ and MoS₂ thin films made by simple and straightforward thermal sulfurization of sputter deposited metal films on silicon chips. The sensor response to H₂, H₂S, CO and NH₃ analytes in air at 30 °C has been assessed and both MoS₂ and WS₂ were found to have an excellent selectivity to NH₃ with a particularly high sensitivity of 0.10 ± 0.02 ppm⁻¹ at sub-ppm concentrations in the case of WS₂. The sensing behavior is explained on the bases of gas adsorption energies as well as carrier (hole) localization induced by the surface adsorbed moieties having reductive nature.

High-performance electromagnetic interference shielding is becoming vital for the next generation telecommunication and sensor devices among which portable and wearable applications require highly flexible and lightweight materials having efficient absorption-dominant shielding. Herein, we report on lightweight carbon foam-carbon nanotube/carbon nanofiber nanocomposites that are synthesized in a two-step robust process including a simple carbonization of open-pore structure melamine foams and subsequent growth of carbon nanotubes/nanofibers by chemical vapor deposition. The microstructure of the nanocomposites resemble a 3-dimensional hierarchical network of carbonaceous skeleton surrounded with a tangled web of bamboo-shaped carbon nanotubes and layered graphitic carbon nanofibers. The microstructure of the porous composite enables absorption-dominant (absorbance ~0.9) electromagnetic interference shielding with an effectiveness of ~20-30 dB and with an equivalent mass density normalized shielding effectiveness of ~800-1700 dB cm³ g^-1 at the K-band frequency (18-26.5 GHz). Moreover, the hydrophobic nature of the materials grants water-repellency and stability in humid conditions important for reliable operation in outdoor use; whereas the mechanical flexibility and durability with excellent piezoresistive behavior enable strain-responsive tuning of electrical conductivity and electromagnetic interference shielding, adding on further functionalities. The demonstrated nanocomposites are versatile and will contribute to the development of reliable devices not only in telecommunication but also in wearable electronics, aerospace engineering and robotics among others.