Ultrafast Heating for Intrinsic Properties of Atomically Thin Two-Dimensional Materials on Plastic Substrates.

Despite recent progress in producing flexible and stretchable electronics based on two-dimensional (2D) nanosheets, their intrinsic properties are often degraded by the presence of polymeric residues that remain attached to the 2D nanosheet surfaces following fabrication. Further breakthroughs are therefore keenly awaited to obtain clean surfaces compatible with flexible applications. Here, we report a method that allows the 2D nanosheets to be intrinsically integrated onto flexible substrates.

Rapid Cellulose-Mediated Microwave Sintering for High-Conductivity Ag Patterns on Paper.

Cellulose-based paper is essential in everyday life, but it also has further potentials for use in low-cost, printable, disposable, and eco-friendly electronics. Here, a method is developed for the cellulose-mediated microwave sintering of Ag patterns on conventional paper, in which the paper plays a significant role both as a flexible insulating substrate for the conductive Ag pattern and as a lossy dielectric media for rapid microwave heating. The anisotropic dielectric properties of the cellulose fibers mean that a microwave electric field applied parallel to the paper substrate provides sufficient heating to produce Ag patterns with a conductivity 29-38% that of bulk Ag in a short period of time (∼1 s) at 250-300 °C.

Sub-second carbon-nanotube-mediated microwave sintering for high-conductivity silver patterns on plastic substrates.

A method of microwave sintering that is mediated by carbon nanotubes (CNTs) has been developed to obtain high-conductivity Ag patterns on the top of heat-sensitive plastic substrates within a short time. The Ag patterns are printed on CNTs formed on plastic substrates and rapidly heated to a great extent by the heat transferred from the microwave-heated CNTs. The conductivity of the microwave-sintered Ag patterns reaches ∼39% that of bulk Ag within 1 s without substrate deformation.

Electrically robust metal nanowire network formation by in-situ interconnection with single-walled carbon nanotubes.

Modulation of the junction resistance between metallic nanowires is a crucial factor for high performance of the network-structured conducting film. Here, we show that under current flow, silver nanowire (AgNW) network films can be stabilised by minimizing the Joule heating at the NW-NW junction assisted by in-situ interconnection with a small amount (less than 3 wt%) of single-walled carbon nanotubes (SWCNTs). This was achieved by direct deposition of AgNW suspension containing SWCNTs functionalised with quadruple hydrogen bonding moieties excluding dispersant molecules.

Microwave flash annealing for stability of chemically doped single-walled carbon nanotube films on plastic substrates.

Microwave flash annealing dramatically enhances the environmental stability of AuCl3-doped single-walled carbon nanotube (SWCNT) films on plastic substrates using fast microwave nanoheating to produce a large temperature difference between the films and the substrates. Within one second, the microwave nanoheating rapidly caused thermal decomposition of AuCl3 dopants as well as simultaneous embedding of SWCNTs in the substrate, without deforming it. The hygroscopic Cl atoms were partially desorbed from the SWCNTs by rapid thermal decomposition, and the embedded substrate surface acted as a passivation layer, which synergistically contributed to the stability of the doped and annealed SWCNTs.

Accelerated esterification of free fatty acid using pulsed microwaves.

It was demonstrated that pulsed microwave irradiation is a more effective method to accelerate the esterification of free fatty acid with a heterogeneous catalyst than continuous microwave irradiation. A square-pulsed microwave with a 400 Hz repetition rate and a 10-20% duty cycle with the same energy as the continuous microwave were used in this study. The pulsed microwaves improved the esterification conversion from 39.