Dopant-Tunable Ultrathin Transparent Conductive Oxides for Efficient Energy Conversion Devices

Abstract

Ultrathin film-based transparent conductive oxides (TCOs) with a broad work function (WF) tunability are highly demanded for efficient energy conversion devices. However, reducing the film thickness below 50 nm is limited due to rapidly increasing resistance; furthermore, introducing dopants into TCOs such as indium tin oxide (ITO) to reduce the resistance decreases the transparency due to a trade-off between the two quantities. Herein, we demonstrate dopant-tunable ultrathin (≤ 50 nm) TCOs fabricated via electric field-driven metal implantation (m-TCOs; m = Ni, Ag, and Cu) without compromising their innate electrical and optical properties. The m-TCOs exhibit a broad WF variation (0.97 eV), high transmittance in the UV to visible range (89–93% at 365 nm), and low sheet resistance (30–60 Ω cm−2). Experimental and theoretical analyses show that interstitial metal atoms mainly affect the change in the WF without substantial losses in optical transparency. The m-ITOs are employed as anode or cathode electrodes for organic light-emitting diodes (LEDs), inorganic UV LEDs, and organic photovoltaics for their universal use, leading to outstanding performances, even without hole injection layer for OLED through the WF-tailored Ni-ITO. These results verify the proposed m-TCOs enable effective carrier transport and light extraction beyond the limits of traditional TCOs.

Coaxial Electrohydrodynamic Printing of Microscale Core–Shell Conductive Features for Integrated Fabrication of Flexible Transparent Electronics

“…The as-printed flexible transparent electronics with a filament spacing of 1000 μm can achieve a sheet resistance of 3.35 Ω/sq and optical transmittance of 98%, indicating a good trade-off between R s and T, which is higher than the performance of recent studies. 29,30 Figure 6f shows the electrothermal profiles of the CEHDprinted microscale core−shell conductive mesh with a filament spacing of 1000 μm under different applied voltages. As the voltage increased from 1 to 10 V, the maximum temperature significantly increased from 23 to 105 °C.…”

“…Accordingly, the sheet resistance ( R s ) of resultant conductive structures, measured by a four-probe method, , increased from 2.94 ± 0.35 Ω/sq to 9.17 ± 0.39 Ω/sq (Figure e). The as-printed flexible transparent electronics with a filament spacing of 1000 μm can achieve a sheet resistance of 3.35 Ω/sq and optical transmittance of 98%, indicating a good trade-off between R s and T , which is higher than the performance of recent studies. , …”

A crack templated copper network film as a transparent conductive film and its application in organic light-emitting diode

“…It has been proved as an alternative to ITO 17 , 18 Hybrid TCFs of Carbon-based materials, metals and conductive polymers can effectively utilize the advantage of a single material and complement the shortcomings of a single material 19 , 20 . Cu-transparent conductive oxides show a broad work function and work as anode or cathode electrodes in organic light-emitting diodes (LEDs) without hole injection layer 21 . Meanwhile, hybrid transparent electrodes can improve charge injection and obtain better current density 22 .…”

All-atmospheric fabrication of Ag–Cu core–shell nanowire transparent electrodes with Haacke figure of merit >600 × 10–3 Ω−1

“…Researchers have developed a number of strategies to displace incumbent ITO, including TCEs based on metal oxides 4 , 5 , carbon nanotubes 6 , 7 , graphene 8 , 9 , conductive polymers 10 , 11 , oxide/metal/oxide strutures 12 – 15 , and metal nanowire networks 15 – 19 . Metal nanowire networks are promising due to their high performance, high scalability, low cost, and flexibility 20 , 21 .…”