- Award ID(s):
- 2003783
- Publication Date:
- NSF-PAR ID:
- 10230107
- Journal Name:
- Nanomaterials
- Volume:
- 11
- Issue:
- 5
- Page Range or eLocation-ID:
- 1148
- ISSN:
- 2079-4991
- Sponsoring Org:
- National Science Foundation
More Like this
-
Printing enabled solution processing of semiconductors, especially Cu-based films, is an inexpensive and low-energy fabrication route for p-type thin-film transistors that are critical components of printed electronics. The state-of-the-art route is limited by a gap between ink compositions that are printable and ink compositions that enable high electrical performance at low processing temperatures. We overcome this gap based on the insight that the hole density of CuI can be tuned by alloying with CuBr while achieving a higher on/off ratio due to the lower formation energy of copper vacancies in CuBr than in CuI. We develop stable and printable precursor inks from binary metal halides that undergo post-printing recrystallization into a dense CuBrI thin film at temperatures as low as 60 °C. Adjusting the CuI/CuBr ratio affects the electrical properties. CuBr 0.2 I 0.8 films achieve the highest field-effect mobility among CuI based thin-film transistors (9.06 ± 1.94 cm 2 V −1 s −1 ) and an average on/off ratio of 10 2 –10 5 at a temperature of 150 °C. This performance is comparable to printed n-type Cu-based TFT that needs temperatures as high as 400 °C. (mobility = 0.22 cm 2 V −1 s −1 , on/off ratiomore »
-
Direct write Inkjet Printing is a versatile additive manufacturing technology that allows for the fabrication of multiscale structures with dimensions spanning from nano to cm scale. This is made possible due to the development of novel dispensing tools, enabling controlled and precise deposition of fluid with a wide range of viscosities (1 – 50 000 mPas) in nano-liter volumes. As a result, Inkjet printing has been recognized as a potential low-cost alternative for several established manufacturing methods, including cleanroom fabrication. In this paper, we present a characterization study of PEDOT: PSS polymer ink deposition printing process realized with the help of an automated, custom Direct Write Inkjet system. PEDOT: PSS is a highly conductive ink that possesses good film forming capabilities. Applications thus include printing thin films on flexible substrates for tactile (touch) sensors. We applied the Taguchi Design of Experiment (DOE) method to produce the optimal set of PEDOT:PSS ink dispensing parameters, to study their influence on the resulting ink droplet diameter. We experimentally determined that the desired outcome of a printed thin film with minimum thickness is directly related to 1) the minimum volume of dispensed fluid and 2) the presence of a preprocessing step, namely air plasmamore »
-
The organic metal halide perovskite material is capable of high throughput manufacturing via traditional deposition processes used in roll-to-roll, yet thermal annealing post deposition may require long ovens. We report rapid annealed perovskite thin films using intense pulsed light (IPL) to initiate a radiative thermal response that is enabled by an alkyl halide additive that collectively improves the performance of a device processed in an ambient environment from a baseline of 10 to 16.5% efficiency. Previous reports on CH 3 NH 3 PbI 3 perovskite films using IPL processing achieved functional devices in milli-second time scales and are promising for high throughput manufacturing processes under ambient conditions. In this study, we found that the addition of diiodomethane (CH 2 I 2 ) as an additive to the methylammonium iodide (MAI)/lead iodide (PbI 2 ) precursor ink chemistry and subsequent IPL thermal annealing are inter-dependent. The concentration of CH 2 I 2 and IPL processing parameters have a direct effect on the surface morphology of the films and performance within a perovskite solar cell (PSC). The CH 2 I 2 dissociates under exposure to ultraviolet (UV) radiation from the IPL source liberating iodine ions in the film, influencing the perovskite formationmore »
-
Abstract Structural color printings have broad applications due to their advantages of long-term sustainability, eco-friendly manufacturing, and ultra-high resolution. However, most of them require costly and time-consuming fabrication processes from nanolithography to vacuum deposition and etching. Here, we demonstrate a new color printing technology based on polymer-assisted photochemical metal deposition (PPD), a room temperature, ambient, and additive manufacturing process without requiring heating, vacuum deposition or etching. The PPD-printed silver films comprise densely aggregated silver nanoparticles filled with a small amount (estimated <20% volume) of polymers, producing a smooth surface (roughness 2.5 nm) even better than vacuum-deposited silver films (roughness 2.8 nm) at ~4 nm thickness. Further, the printed composite films have a much larger effective refractive index
n (~1.90) and a smaller extinction coefficientk (~0.92) than PVD ones in the visible wavelength range (400 to 800 nm), therefore modulating the surface reflection and the phase accumulation. The capability of PPD in printing both ultra-thin (~5 nm) composite films and highly reflective thicker film greatly benefit the design and construction of multilayered Fabry–Perot (FP) cavity structures to exhibit vivid and saturated colors. We demonstrated programmed printing of complex pictures of different color schemes at a high spatial resolution of ~6.5 μm by three-dimensionally modulating the top composite film geometries andmore » -
Low-cost materials, scalable manufacturing, and high power conversion efficiency are critical enablers for large-scale applications of photovoltaic (PV) cells. Cu 2 ZnSn(S,Se) 4 (CZTSSe) has emerged as a promising PV material due to its low-cost earth-abundant nature and the low toxicity of its constituents. We present a compact and environmentally friendly route for preparing metal sulfide (metals are Cu, Zn, and Sn) nanoparticles (NPs) and optimize their annealing conditions to obtain uniform carbon-free CZTSSe thin films with large grain sizes. Further, the solution-stable binary NP inks synthesized in an aqueous solution with additives are shown to inhibit the formation of secondary phases during annealing. A laboratory-scale PV cell with a Al/AZO/ZnO/CdS/CZTSSe/Mo-glass structure is fabricated without anti-reflective coatings, and a 9.08% efficiency under AM1.5G illumination is demonstrated for the first time. The developed scalable, energy-efficient, and environmentally sustainable NP synthesis approach can enable integration of NP synthesis with emerging large-area deposition and annealing methods for scalable fabrication of CZTSSe PV cells.