A polymer electrolyte design enables ultralow-work-function electrode for high-performance optoelectronics

Converting a Metal-Coordinating Polymer to a Polymerized Ionic Liquid Improves Li+ Transport

Solid polymer electrolytes (SPEs) with mechanical strength and reduced flammability may also enable next-generation Li+ batteries with higher energy densities. However, conventional SPEs have fundamental limitations in terms of Li+ conductivity. While an imidazole functionalized polymer (PMS-Im) has been previously shown to have ionic conductivity related to the imidazole-Li+ coordination, herein we demonstrate that quaternization of this polymer to form an analogous imidazolium functionalized polymer (PMS-Im+) more efficiently solvates lithium salts and plasticizes the polymer. In addition, inverse Haven ratios as high as 10 indicate positively correlated Li+ transport, possibly due to percolation of nanochannels that significantly improve battery-relevant conductivity. From these combined effects, Li+ conductivity in PMS-Im+ (2.1 × 10-5 S/cm) is over an order of magnitude greater than in PMS-Im at 90 °C (1.6 × 10-6 S/cm).

Photo-Modulated Ionic Polymer as an Adaptable Electron Transport Material for Optically Switchable Pixel-Free Displays

In addition to electrically driven organic light-emitting diode (OLED) displays that rely on complicated and costly circuits for switching individual pixel illumination, developing a facile approach that structures pixel-free light-emitting displays with exceptional precision and spatial resolution via external photo-modulation holds significant importance for advancing consumer electronics. Here, optically switchable organic light-emitting pixel-free displays (OSPFDs) are presented and fabricated by judiciously combining an adaptive photosensitive ionic polymer as electron transport materials (ETM) with external photo-modulation as the switching mode while ensuring superior illumination performance and seamless imaging capability. By irradiating the solution-processed OSPFDs with light at specific wavelengths, efficient and reversible tuning of both electron transport and electroluminescence is achieved simultaneously. This remarkable control is achieved by altering the energetic matching within OSPFDs, which also exhibits a high level of universality and adjustable flexibility in the three primary color-based light-emitting displays. Moreover, the ease of creating and erasing desired pixel-free emitting patterns through a non-invasive photopatterning process within a single OSPFD is demonstrated, thereby rendering this approach promising for commercial displaying devices and highly precise pixelated illuminants.

Fully-Solution-Processed Enhancement-Mode Complementary Metal-Oxide-Semiconductor Carbon Nanotube Thin Film Transistors Based on BiI3 -Doped Crosslinked Poly(4-Vinylphenol) Dielectrics for Ultralow-Power Flexible Electronics

The threshold voltage (V_th ) adjustment of complementary metal-oxide-semiconductor (CMOS) thin film transistors (TFTs) is one of the research hotspots due to its key role in energy consumption control of CMOS circuits. Here, ultralow-power flexible CMOS circuits based on well-matched enhancement-mode (E-mode) CMOS single-walled carbon nanotube (SWCNT) TFTs are successfully achieved through tuning the work function of gate electrodes, electron doping, and printing techniques. E-mode P-type CMOS SWCNT TFTs with the full-solution procedure are first obtained through decreasing the work function of Ag gate electrodes directly caused by the deposition of bismuth iodide (BiI₃ )-doped solid-state electrolyte dielectrics. After synthetic optimization of dielectric compositions and semiconductor printing process, the flexible printed E-mode SWCNT TFTs show the high I_on /I_off ratios of ≈10⁶ , small subthreshold swing (SS) of 70-85 mV dec^-1 , low operating voltages of ≈0.5 to -1.5 V, good stability and excellent mechanical flexibility during 10 000 bending cycles. E-mode N-type SWCNT TFTs are then selectively achieved via printing the polarity conversion ink (2-Amino-2-methyl-1-propanol (AMP)  as electron  doping agent) in P- type TFT channels. Last, printed SWCNT CMOS inverters are successfully constructed with full rail-to-rail output characteristics and the record unit static power consumption of 6.75 fW µm^-1 at V_DD of 0.2 V.