A printable elastic silver ink has been developed, which was made of silver flakes, dispersant, and a fluorine rubber and could be sintered at a low temperature. The printed elastic conductors showed low resistivity at 21 μΩ·cm, which is about 13.2 times of bulk silver (1.59 μΩ·cm). Their mechanical properties were investigated by bending, stretching, and cyclic endurance tests. It was found that upon stretching the resistance of printed conductors increased due to deformation and small cracks appeared in the conductor, but was almost reversible when the strain was removed, and the recovery of conductivity was found to be time dependent. Radio-frequency identification (RFID) tags were fabricated by screen printing the stretchable silver ink on a stretchable fabric (lycra). High performance of tag was maintained even with 1000 cycles of stretching. As a practical example of wearable electronics, an RFID tag was printed directly onto a T-shirt, which demonstrated its normal working order in a wearing state.

Near infrared (NIR) sintering technology is a photonic sintering approach for metal nanoparticles, which can selectively sinter metal nanoparticles more quickly and efficiently, it is also compatible with high-throughput manufacturing processes.

In this paper, we reported the realization of fully printed flexible ultra-low voltage single-walled carbon nanotube (SWCNT) thin film transistors (TFTs) and CMOS inverters at temperatures lower than 170 °C using ionic liquid (IL) crosslinked-poly(4-vinylphenol) as the composite solid state electrolyte dielectric layer. Optimized fully printed p-type SWCNT-TFTs exhibited good performance with an average field effect mobility of 6.6 cm² V⁻¹ s⁻¹, an ON/OFF ratio above 10⁶, a small hysteresis (100 mV), and a subthreshold swing (SS) as low as 95 mV dec⁻¹ at low operating gate voltages (±0.75 V). Converting the polarity from p-type into n-type using epoxy amine inks enables us to fabricate fully printed low-voltage SWCNT CMOS inverters. The power dissipation could be decreased by decreasing the number of printing cycles of sc-SWCNT inks in device channels. The peak power dissipation of the resulting flexible CMOS inverters could reach 6 nW and V_DD is down to 0.5 V along with a voltage gain of 10 and a maximum noise margin of 0.28 V (∼56% of V_DD/2). To the best of the authors’ knowledge, the voltage gain, noise margin and static power consumption values achieved in this work are the best values reported to date in the literature for fully printed SWCNT inverters.

A universal roll-to-roll (R2R) printing approach was developed to construct large area (8 cm × 14 cm) semiconducting single-walled carbon nanotube (sc-SWCNT) thin films on flexible substrates (such as polyethylene terephthalate (PET), paper, and Al foils) at a printing speed of 8 m min⁻¹ using highly concentrated sc-SWCNT inks and crosslinked poly-4-vinylphenol (c-PVP) as the adhesion layer. Bottom-gated and top-gated flexible printed p-type TFTs based on R2R printed sc-SWCNT thin films exhibited good electrical properties with a carrier mobility of ∼11.9 cm² V⁻¹ s⁻¹, I_on/I_off ratios of ∼10⁶, small hysteresis, and a subthreshold swing (SS) of 70–80 mV dec⁻¹ at low gate operating voltages (±1 V), and excellent mechanical flexibility. Furthermore, the flexible printed complementary metal oxide semiconductor (CMOS) inverters demonstrated rail-to-rail voltage output characteristics under an operating voltage as low as V_DD = −0.2 V, a voltage gain of 10.8 at V_DD = −0.8 V, and power consumption as low as 0.056 nW at V_DD = −0.2 V. To the best of our knowledge, the electrical properties of the printed SWCNT TFTs (such as I_on/I_off ratio, mobility, operating voltage, and mechanical flexibility) and printed CMOS inverters based on the R2R printed sc-SWCNT active layer in this work are excellent compared to those of R2R printed SWCNT TFTs reported in the literature. Consequently, the universal R2R printing method reported in this work could promote the development of fully printed low-cost, large-area, high-output, and flexible carbon-based electronics.