Desktop Inkjet Printer Research Articles

A Study of All-solid-state Planar Micro-supercapacitors Using Printable MoS2 Inks

Wearable energy storage electronics with high safety and long life have been promising candidates in recent years. Herein, all-solid-state planar micro-supercapacitors (MSCs) were demonstrated by inkjet printing of molybdenum disulfide (MoS2) electrodes. The preprinted PEDOT: PSS film on PI (Polyimide) substrate prepared with a simple and low-cost desktop inkjet printer can greatly improve the electrode conductivity. Additionally, the obtained planar MSCs show good electrochemical performance with high areal capacitance of 323 µF cm−2 and areal energy density of 0.016 µWh cm−2. More importantly, the MSCs exhibit outstanding flexibility with almost no degradation under various bending angles. The capacitance retention can still be maintained at 88.5% even after 8000 cycles, indicating good cycle stability of MSCs. The in-plane flexible MSCs hold great application potential for wearable and integrated energy storage electronics.

Data-enriched edible pharmaceuticals (DEEP) of medical cannabis by inkjet printing.

Medical cannabis has shown to be effective in various diseases that have not successfully been treated with other marketed drug products. However, the dose of cannabis is highly individual and additionally, medical cannabis is prone to misuse. To combat these challenges, the concept of data-enriched edible pharmaceuticals (DEEP) is introduced. Quick Response (QR) code patterns containing lipophilic cannabinoids, i.e., cannabidiol (CBD) and delta-9-tetrahydrocannabinol (THC), were printed using a desktop inkjet printer. This allows for simultaneously printing an individual dose and encapsulating information relevant to the end-users and other stakeholders in a single dosage unit, which is readable by a standard smartphone. Different doses of CBD and THC were incorporated in the DEEP by printing various (1-10) layers of the cannabinoid-containing ink on porous substrates, i.e., solid foams, prepared by solvent casting and subsequent freeze-drying. The printed DEEP were still readable after 8weeks of storage in dry and cold conditions. This approach of 'in-drug labeling' instead of 'drug package labeling' provides a new possibility for developing a more efficient supply chain of pharmaceuticals and safer medication schemes by increasing the traceability of drug products at a single dosage unit level.

Inkjet-Printed Ultrathin MoS2-Based Electrodes for Flexible In-Plane Microsupercapacitors.

Flexible and wearable energy storage microdevice systems with high performance and safety are promising candidates for the electronics of on-chip integration. Herein, we demonstrate inkjet-printed ultrathin electrodes based on molybdenum disulfide (MoS2) nanosheets for flexible and all-solid-state in-plane microsupercapacitors (MSCs) with high capacitance. The MoS2 nanosheets were uniformly dispersed in the low-boiling point and nontoxic solvent isopropanol to form highly concentrated inks suitable for inkjet printing. The MSCs were assembled by printing the highly concentrated MoS2 inks on a polyimide substrate with appropriate surface tension using a simple and low-cost desktop inkjet printer. Because of the two-dimensional structure of MoS2 nanosheets, the as-assembled planar MSCs have high loadings of active materials per unit area, resulting in more flexibility and thinness than the capacitors with a traditional sandwich structure. These planar MSCs can not only possess any collapsible shape through the computer design but also exhibit excellent electrochemical performance (with a maximum energy density of 0.215 mW h cm-3 and a high-power energy density of 0.079 W cm-3), outstanding mechanical flexibility (almost no degradation of capacitance at different bending radii), good cycle stability (85.6% capacitance retention even after 10,000 charge-discharge cycles), and easy scale-up. Moreover, a blue light-emitting diode can be powered using five MSCs connected in series. The in-plane and low-cost MSCs with high energy densities have great application potential for integrated energy storage systems including wearable planar solar cells and other electronics.

Flexible printed paper electrode with silver nano-ink for electrochemical applications

Development of low-cost paper based disposable electrodes printed with silver nano-ink using desktop inkjet printer is reported in this work. A stable nano-ink was prepared by dissolving 3% silver nanoparticles (AgNPs) capped with polyvinylpyrrolidone (PVP) in ethanol as a dispersing solvent. Highly stable silver nano-ink with surface tension of 21.1 mN/M and viscosity of 2.6 mPa.S was prepared for printing on photo paper that can be used as an electrode for electrochemical analyses. The fabricated paper electrode was exploited as a counter electrode in cyclic voltammetry (CV) analysis of potassium ferricyanide with better stability and reproducibility (relative standard deviation (RSD) 1.6%) for multiple times of analyses (n = 60) and compared with the results of conventional electrodes. Further, the printed paper electrode was demonstrated to be used as a working electrode for analysis of nitrate by CV. The use of paper electrode is found to be simple, rapid, user-friendly and can be applied at the sample source for determination of nitrate from different samples.

Evaluation of Planar Inkjet-Printed Antennas on a Low-Cost Origami Flapping Robot

An investigation on antenna solutions for expendable origami paper flapping robots is presented. An origami flapping robotic bird that can be produced using standard A4 paper is employed. Antennas resonating at the two commonly used frequency bands, 2.4 GHz and 5.2 GHz, are designed for the limited space available on the folded origami structure. Two developments of the same dual-band monopole antenna are discussed. The first antenna is located on the robot's spine and the second on its tail. A space diversity configuration is also studied. The antennas are printed directly onto a photo paper substrate and then folded into an origami robotic crane's body structure. An ordinary desktop inkjet printer fitted with silver nanoparticle conductive ink cartridges has been employed. CST Microwave Studio TM has been used to design the antennas. A good agreement between the measured and simulated S11 results is achieved with a reasonable -10dB impedance bandwidth realized in the three cases studied. The radiation patterns are omnidirectional in the XZ plane which is desirable for the specific application. The diversity configuration has a mutual coupling of <; -23dB and a gain of 1.4 dB and 2.8 dB at 2.4 GHz and 5.2 GHz respectively. The aim is to provide a new vision for antennas embedded into expandable flying robots based on traditional origami structures.

TiO2 Nanofilms on Polymeric Substrates for the Photocatalytic Degradation of Methylene Blue

A low-temperature process to synthesize and print photoactive TiO2 nanofilms onto polymeric substrates using a modified desktop inkjet printer is presented. The coated substrates were assembled in ...

Inkjet-Printed High-Q Nanocrystalline Diamond Resonators.

Diamond is a highly desirable material for state-of-the-art micro-electromechanical (MEMS) devices, radio-frequency filters and mass sensors, due to its extreme properties and robustness. However, the fabrication/integration of diamond structures into Si-based components remain costly and complex. In this work, a lithography-free, low-cost method is introduced to fabricate diamond-based micro-resonators: a modified home/office desktop inkjet printer is used to locally deposit nanodiamond ink as ∅50-60 µm spots, which are grown into ≈1 µm thick nanocrystalline diamond film disks by chemical vapor deposition, and suspended by reactive ion etching. The frequency response of the fabricated structures is analyzed by laser interferometry, showing resonance frequencies in the range of ≈9-30 MHz, with Q-factors exceeding 104 , and (f0 × Q) figure of merit up to ≈2.5 × 1011 Hz in vacuum. Analysis in controlled atmospheres shows a clear dependence of the Q-factors on gas pressure up until 1 atm, with Q ∝ 1/P. When applied as mass sensors, the inkjet-printed diamond resonators yield mass responsivities up to 981 Hz fg-1 after Au deposition, and ultrahigh mass resolution up to 278 ± 48 zg, thus outperforming many similar devices produced by traditional top-down, lithography-based techniques. In summary, this work demonstrates the fabrication of functional high-performance diamond-based micro-sensors by direct inkjet printing.

Inkjet‐Printed Random Lasers

AbstractPrinting technology has led to a multitude of revolutions in design, conception, fabrication, and application of optoelectronics nowadays especially for wearables and one‐off devices. Recent advances range from solar cells, batteries, sensors, LEDs, displays, biomedical widgets to smart tags. Inkjet‐printed random lasers (IPRLs), demonstrated here, fill in the crucial but missing piece of the puzzle in printed optoelectronics as well as progress in laser research. A broad emission spectrum of IPRL inks covering more than 75% gamut of CIE color space is successfully exploited and well adopted by commercial desktop inkjet printers. Furthermore, based on the digital, ink‐efficient, mask‐free patterning, and drop‐on‐demand printing technique, a series of long‐anticipated proofs‐of‐concept including on‐chip laser lighting modules, red‐yellow‐green‐blue pixel‐based laser displays, and ink‐crypto/laser‐coded security printing technique are also demonstrated.

A Novel Metamaterial Inspired High-Temperature Microwave Sensor in Harsh Environments.

A high-temperature sensor based on a metamaterial unit cell is proposed in this paper. The wireless passive temperature sensing method is based on the electromagnetic backscatter principle, and thus has the advantages of higher quality, lower environmental interference, and anti-low frequency interference. We developed a finite-element method-based model for the sensor via high-frequency simulation software (HFSS). A double split-ring resonator (SRR) with an outer ring length of 13 mm was designed on alumina ceramic substrate. The sensor was fabricated at 2.42 GHz using micromechanical technology and screen printing technology. When the temperature increased from 28 to 1100 °C, the resonant frequency decreased from 2.417 to 2.320 GHz with an average sensitivity of 95.63 kHz/°C. As the sensor is easily designed and fabricated, it can be used for chipless radio frequency identification (RFID) tags by simply changing the size of rings. Furthermore, emerging 3D printing technology and commercial desktop inkjet printers will be used to realize the rapid low-cost preparation of the sensor, enabling its wide range of applications in aerospace, military, manufacturing, transportation, and other fields.

Inkjet-Based Fabrication Process with Control over the Morphology of SERS-Active Silver Nanostructures

Morphological control of silver nanostructures is sought after due to the dependence of optical properties on size and shape. Herein, we report a facile printing process for fabricating silver nanostructured films with wire-like or particle-like morphologies on paper by merely varying the halide composition of precursor salt from potassium bromo-iodide to potassium chloride. Silver was efficiently retained on the top surface of porous paper substrates by printing an excess of potassium halide salt first, leading to more conductive films at lower silver loadings. Furthermore, Raman characterization results show that silver films having nanoparticle morphology have higher SERS activity than samples with nanowire morphology, although the roughness factor of nanowire films is higher than the corresponding nanoparticulate film. Overall, these findings highlight a facile process for controlling the morphology of SERS-active silver nanostructures, which are fabricated on paper using a desktop inkjet printer.

Accessing individual 75-micron diameter nozzles of a desktop inkjet printer to dispense picoliter droplets on demand.

Desktop inkjet printers are ubiquitous and relatively inexpensive among the variety of available printers. These inkjet printers use an array of micro fluidic pumps, nozzles based on piezoelectric actuation, to dispense individual picoliter volume ink droplets at high speed. In this paper, we show that individual pumps in desktop printers can be accessed to dispense droplets on demand. Access was obtained using the printer’s command language programming. A detailed description of the access procedure is discussed. Droplets were printed on a paper as it rolled underneath the printhead, and with a minor hardware modification, they were also printed on a glass substrate. With this access, individual droplets were deposited, the smallest having an average diameter of 62 μm with a standard deviation of 6.9 μm, with a volume of ∼4 pL. From the intended position, the droplets had a standard deviation of 5.4 μm and 8.4 μm in the vertical and horizontal directions, respectively. The ink droplets were dispensed at a rate of 7.1 kHz. A circularity factor of 0.86 was obtained indicating that the dispensed droplets are of good quality. By replacing the ink in the cartridges with liquids of choice (e.g. cells, proteins, nanoparticles etc.), we believe it provides an opportunity for low-cost, high-speed, high-precision, picoliter volume printing for a variety of applications.

Fabrication of PEDOT:PSS/Graphene Conductive Ink Printed on Flexible Substrate

Nowadays, flexible electronic is an important technology to produce flexible electronic devices due to it offers the attractive features such as possibility of product types and designs, with reducing size and weight, and low cost. Poly (3,4-ethelenedioxythiophene):poly (stylenesulfonate) (PEDOT:PSS) is a conductive polymer which possess high conductivity, high electrochemical, and low redox potential. PEDOT:PSS and PEDOT:PSS/Graphene (GP)/Dimethyl sulfoxide (DMSO) conductive ink ware deposited on Polyethylene terephthalate (PET) flexible substrate using desktop inkjet printer. Conductivity and thickness of conductive pattern at 1, 3, 5, 10, 20 layers were investigated in this study. It is observed that sheet resistivity of the conductive pattern is influenced by number of printed layers. Addition of GP at 20 layers of PEDOT:PSS/GP/DMSO conductive pattern exhibits the lowest sheet resistivity at 44 ohm/󠇯󠇯sq compared to PEDOT:PSS conductive pattern of 1.81×104 ohm/󠇯󠇯sq.

Printed Paper Robot Driven by Electrostatic Actuator

Effective design and fabrication of 3-D electronic circuits are among the most pressing issues for future engineering. Although a variety of flexible devices have been developed, most of them are still designed two-dimensionally. In this letter, we introduce a novel idea to fabricate a 3-D wiring board. We produced the 3-D wiring board from one desktop inkjet printer by printing conductive pattern and a 2-D pattern to induce self-folding. We printed silver ink onto a paper to realize the conductive trace. Meanwhile, a 3-D structure was constructed with self-folding induced by water-based ink printed from the same printer. The paper with the silver ink self-folds along the printed line. The printed silver ink is sufficiently thin to be flexible. Even if the silver ink is already printed, the paper can self-fold or self-bend to consist the 3-D wiring board. A paper scratch driven robot was developed using this method. The robot traveled 56 mm in 15 s according to the vibration induced by the electrostatic force of the printed electrode. The size of the robot is 30 × 15 × 10 mm. This work proposes a new method to design 3-D wiring board, and shows extended possibilities for printed paper mechatronics.

Inkjet printed electroadhesive pads on paper

Astriction between two closely spaced surfaces interacting through fringing electric fields is termed as electroadhesion. Polarisation-induced Coulombic attraction forces at the interface result in electroadhesion. The ability to switch on and off adhesion forces by electrical switching and absence of chemical residues upon detachment are some of the attractive features of electroadhesive devices. To avoid static discharges for ensuring safety and for generating uniform forces, a planar interdigitated pattern on an insulating surface with adjacent fingers being oppositely polarised is the preferred mode of operation for electroadhesive devices. A compliant substrate is required to ensure maximum contact that can lead to practically useful adhesive forces per unit surface area of the electrode. Till now, lithographically-patterned electrodes on polymeric substrates represent the state-of the art in terms of fabricating electroadhesive devices. Herein, we report a low-cost route for fabricating interdigitated electrodes on paper using a desktop inkjet printer, which involves alternate printing of silver salt and potassium bromide/potassium iodide solution, in conjunction with silver halide photographic development process. Typically, electrodes with spacing approximate to 1 mm can be routinely fabricated using a standard office desktop printer. We discovered that in samples where a fixing step was not used to remove excess silver salts, the gaps were reduced further to few hundreds of micron length scales when a high voltage is applied, which can pave the way to higher electric field strength and greater adhesion forces. The results of characterisation of these samples using FESEM, XRD, XPS, sheet resistance and shear load testing will be discussed.

Inkjet printing of TiO2/AlOOH heterostructures for the formation of interference color images with high optical visibility.

This paper describes a practical approach for the fabrication of highly visible interference color images using sol-gel ink technique and a common desktop inkjet printer. We show the potential of titania-boehmite inks for the production of optical heterostructures on various surfaces, which after drying on air produce optical solid layers with low and high refractive index. The optical properties of the surface heterostructures were adjusted following the principles of antireflection coating resulting in the enhancement of the interference color optical visibility of the prints by as much as 32%. Finally, the presented technique was optimized following the insights into the mechanisms of the drop-surface interactions and the drop-on-surface coalescence to make it suitable for the production of even thickness coatings suitable for printing at a large scale. We propose that the technology described herein is a promising new green and sustainable approach for color printing.

Inkjet printing of transparent sol-gel computer generated holograms

In this paper we report for the first time a method for the production of transparent computer generated holograms by desktop inkjet printing. Here we demonstrate a methodology suitable for the development of a practical approach towards fabrication of diffraction patterns using a desktop inkjet printer and nonocrystalline sol-gel ink. In particular, the reported inkjet printing method can be used to generate transparent diffraction structures on supports such as those widely applied in security technologies. Transparent highly refractive layers were deposited with a high precision via a wet-to-dry printing method based on the sol-gel transition phenomenon. With this approach we were able to print a diffraction pattern by TiO2 xerogel, with which a transparent computer generated hologram was created. We argue that this new technology can form the foundation for a new generation of commercial protective coating technologies applied by industrial inkjet printing.

Wearable Inkjet-Printed Wideband Antenna by Using Miniaturized AMC for Sub-GHz Applications

A novel compact wearable antenna printed on paper is presented. The antenna comprises a nonresonant coplanar monopole antenna placed on a miniaturized artificial magnetic conductor (AMC) (total size of 0.14 λ0 × 0.14 λ0 × 0.01 λ0 at 700 MHz). The manufacturing process only requires a commercial desktop inkjet printer and conductive nano-ink. The effectiveness of the proposed configuration (monopole above AMC) with respect to the unloaded monopole or to the monopole above a metallic ground plane is proved with on-body measurements in the sub-GHz band.

Rapid combinatorial screening of inkjet-printed alkyl-ammonium cations in perovskite solar cells

Herein we demonstrate that efficient perovskite solar cells can be fabricated by a desktop multi-channel inkjet printer. In this approach, different alkyl-ammonium counterions were loaded separately into the printer cartridges and deposited onto PbI2 coated substrates. Structural as well as electronic properties of perovskite solar cells can be tuned by varying the composition ratio of multiple cations in-situ through the RGB color codes of the multi-channel inkjet printer. This roll-to-roll compatible technique provides rapid and facile screening of multiple and mixed counterion perovskite solar cell systems with high reproducibility, potentially leading to possibilities of high-throughput screening technique in future perovskite solar cell fabrication.

A New Anti‐Counterfeiting Feature Relying on Invisible Luminescent Full Color Images Printed with Lanthanide‐Based Inks

Europium and terbium trisdipicolinate complexes are inkjet printed onto paper with commercially available desktop inkjet printers. Together with a commercial blue luminescent ink, the red‐emitting luminescent ink containing europium and the green‐emitting luminescent ink containing terbium are used to reproduce accurate full color images that are invisible under white light and appear under a 254 nm UV light. Such invisible luminescent images are attractive anti‐counterfeiting security features. The luminescent prints have a color range (gamut) nearly as wide as the gamut of a standard sRGB display. The gamut of the luminescent prints is determined by relying on a simple model predicting the relative spectral radiant emittances of any printed luminescent color halftone. The model is also used to establish the correspondence between the surface coverages of the printed luminescent inks and the emitted color of these luminescent halftones. The accuracy of the spectral prediction model is very good and can be rationalized by the absence of quenching when the luminescent lanthanide complexes are printed in superposition with the other luminescent materials.

Mapping the fine specificity of ABO monoclonal reagents with A and B type-specific function-spacer-lipid constructs in kodecytes and inkjet printed on paper.

Monoclonal (MoAb) reagents are routinely used and are usually very reliable for the serologic determination of ABO blood types. However, the fine specificity and cross-reactivity of these reagents are often unknown, particularly against synthetic antigens used in some diagnostic assays. If nonserologic assays or very sensitive techniques other than those specifically prescribed by the manufacturer are used, then there is a risk of incorrect interpretation of results. Forty-seven MoAbs and two polyclonal ABO reagents were tested against red blood cell (RBC) kodecytes prepared with A trisaccharide, A Type 1, A Type 2, A Type 3, A Type 4, B trisaccharide, B Type 1, B Type 2, acquired B trisaccharide, and Le(a) trisaccharide function-spacer-lipid (FSL) constructs. Natural RBCs were tested in parallel. In addition these FSL constructs were printed onto paper with a desktop inkjet printer and used in a novel immunoassay that identifies reactivity through the appearance of alphanumeric characters. Mapping of MoAbs with kodecytes and printed FSL constructs revealed a series of broad recognition patterns. All ABO MoAbs tested were reactive with the RBC dominant Type 2 ABO antigens. Unexpectedly some anti-A reagents were reactive against the B Type 1 antigen, while others were poorly reactive with trisaccharide antigens. All ABO MoAbs detect the RBC dominant Type 2 ABO antigens; however, some reagents may show minor reactivity with inappropriate blood group antigens, which needs to be considered when using these reagents in alternative or highly sensitive analytic systems.