Indium Tin Oxide Polyethylene Terephthalate Research Articles

Damage-free non-mechanical transfer strategy for highly transparent, stretchable embedded metallic micromesh electrodes

Stretchable, flexible, transparent electrodes garner significant research interest as indispensable components of flexible optoelectronic devices. However, frequent mechanical transfers during processing pose a considerable challenge in preparing electrodes of scalable size with superior performance and intact structure. Herein, we present a stretchable embedded metallic micromesh (SEMM) electrode with high optoelectronic and robust mechanical properties. The SEMM electrode is fabricated via a damage-free non-mechanical transfer strategy with the assistance of a bifunctional metal transition layer that serves as both a seed layer during electrodeposition and a sacrificial layer during stripping of the electrode. Consequently, the SEMM electrode features a scalable size and an intact structure. By optimizing the electrodeposition parameters, the SEMM achieves high optical transmittance (∼83 %) and low sheet resistance (0.22 Ω sq−1), with a figure of merit reaching 8600–53 times greater than that of commercial polyethylene terephthalate-indium tin oxide (PET-ITO). Furthermore, the SEMM exhibits excellent mechanical stability, enduring up to 60 % of tensile strain and maintaining almost constant normalized resistance after 20,000 bending cycles. Based on the SEMM, a transparent film heater yields rapid response time, low operating voltage, and fast defogging capability. This non-mechanical transfer strategy offers a compelling approach for enhancing the structural integrity and scalability of stretchable embedded transparent electrodes.

Fabrication of ultra-sensitive and disposable electrochemical biosensor: Detection of kidney injury molecule-1 protein in urine for diagnosis of kidney injury

This research study indicates the development of the indium tin oxide-polyethylene terephthalate (ITO-PET) coated electrode-based electrochemical biosensor system to sensitively and specifically detect kidney injury molecule-1 (KIM-1), an acute kidney injury (AKI) biomarker. The ITO-PET electrode surface was modified with 3-(Trimethoxysilyl)-1-propanethiol (3-TMESP) silane agent. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and single frequency impedance (SFI) techniques were utilized to examine the interactions between anti-KIM-1 antibody and KIM-1 antigen. The ITO-PET electrode surface was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM) to analyze the morphological characterization at each electrode development stage. Optimization studies have been conducted to determine the optimal concentrations for detecting the 3-TMESP silane agent, the NHS crosslinker, the anti-KIM-1 antibody, and the optimum incubation period for the anti-KIM-1 antibody and the KIM-1 antigen. Analytical characteristic properties of the developed biosensor, including linear determination range, and the studies of reproducibility, regeneration, repeatability, storage life, and selectivity were investigated. The KIM-1 biosensor system, based on 3-TMESP, has a broad linear range and is capable of providing sensitive measurements between 0.1 fg/mL and 1000 fg/mL. The values of low limits of detection (0.26 fg/mL) and of quantification (0.87 fg/mL) were calculated, highlighting its high sensitivity and precision in detecting KIM-1. In addition, five different commercially purchased human urine samples were tested to validate the practicability of the developed biosensor.

The Improvement of Luminous Uniformity of Large-Area Organic Light-Emitting Diodes by Using Auxiliary Electrodes

The study developed a large emission area of flexible blue organic light-emitting diodes (BOLED) on a polyethylene terephthalate/ Indium tin oxide (PET/ITO) substrate using a polycyclic skeleton ν-DABNA Thermally Activated Delayed Fluorescence (TADF) material. Initially, a 1 × 1 cm2 blue OLED was fabricated to optimize the layer thickness. The blue OLED structure consisted of PET/ITO/HATCN/TAPC/UBH-21:ν-DABNA/TPBi/LiF/Al. However, as the emission area increased to 3.5 × 3.5 cm2, the current density decreased due to the resistance of PET/ITO, leading to luminance non-uniformity. To address this issue, auxiliary Au lines were added to the ITO anode to enhance current injection. Despite this, when the Au lines reached a thickness of 30 nm, average light emission was disrupted. To improve the luminescence characteristics of large-area PET/ITO OLEDs, a capping and planarization layer of PEDOT:PSS was applied. Grid uniformity revealed a significant increase in overall luminance uniformity from 74.1% to 87.4% with the addition of auxiliary Au lines. Further increases in grid line density slightly reduced uniformity but enhanced brightness, resulting in brighter, flexible, large-area blue OLED lighting panels.

A single-use electrochemical biosensor system for ultrasensitive detection of Aflatoxin B1 in rice, corn, milk, peanut, chili pepper samples

Aflatoxin B1, a common food contaminant in peanuts and corn and a genotoxic carcinogen in humans poses a significant risk for hepatocellular carcinoma, making its detection crucial; this study aims to develop a label-free electrochemical biosensor using a disposable indium tin oxide polyethylene terephthalate (ITO-PET) electrode modified with 3-Aminopropyltriethoxysilane for detecting Aflatoxin B1 in real food samples. Initially, optimization steps for the proposed biosensor were conducted using electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques. Characterization steps such as storage capacity, regeneration, and single frequency impedance (SFI) were completed for the proposed disposable biosensor after the optimization steps. The electrochemical biosensor, based on AFB1, exhibited excellent repeatability and reproducibility. It had a broad dynamic detection range from 0.1 fg/mL to 500 fg/mL, with low limits of detection (LOD) and quantitation (LOQ) at 0.19 fg/mL and 0.65 fg/mL, respectively. Finally, the proposed AFB1-based biosensor system was applied to real food samples (rice, chili pepper, milk, corn, and peanuts) for testing and validation.

An unusual impedimetric biosensor design based on 3-MPDS for highly sensitive detection of AFB1 in food samples

Aflatoxin B1 (AFB1), a mycotoxin produced by fungi of the genus Aspergillus, particularly Aspergillus flavus, is recognized as the aflatoxin with the highest carcinogenic and mutagenic potential. This study presents a cost-effective, disposable AFB1 biosensor system based on 3-mercaptopropyltrimethoxysilane (3-MPDS) and the highly sensitive impedance technique. The surfaces of the ITO-PET (indium tin oxide/polyethylene terephthalate) electrodes were modified with 3-MPDS, and N-hydroxysuccinimide (NHS) was used as a crosslinker. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques were employed for immobilization, optimization, and analytical studies. Additionally, the surface morphology of the biosensor was analyzed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The biosensor demonstrated a linear range from 0.01 fg/mL to 200 fg/mL, with a limit of detection (LOD) of 0.01 fg/mL and a limit of quantification (LOQ) of 0.04 fg/mL. Finally, the proposed biosensor was tested and validated with real food samples, including rice, peanuts, milk, chili pepper, and corn.

A Flexible Electrochromic Device for All-Season Thermal Regulation on Curved Transparent Building Envelopes.

As one of the least energy-efficient components in buildings, transparent building envelopes are responsible for approximately 60% of the total energy losses. Although controlling solar transmittance through electrochromic modulation is an effective method for temperature management in these structures, a dynamic control strategy for solar light on curved transparent building envelopes is still lacking. In this study, we introduce a dual-mode flexible electrochromic device based on reversible silver deposition for curved transparent building envelopes. The device operates by reversibly depositing and dissolving silver on a flexible polyethylene terephthalate-indium tin oxide (PET-ITO) substrate, controlled through the application and removal of pulsed voltage. This mechanism enables rapid switching between radiative cooling and solar heating modes, leading to modulation of solar reflectance from 89.1% to 15.7% and solar transmittance from 0.02% to 72.9%. Under approximately 700 W/m2 of solar irradiance, the device achieves an average temperature reduction of 1.6 °C (with a maximum reduction of 4.3 °C) compared to ambient temperature in radiative cooling mode. In solar heating mode, the device achieves an average temperature increase of 17.1 °C (with a maximum increment of 23.7 °C) compared to ambient temperature. Simulation results show that the dual-mode flexible electrochromic device could offer all-season thermal regulation for curved transparent building envelopes and achieve a maximum of over 50% annual HVAC energy savings.

Preparation of poly(5‐ferrocenyl‐dipyrromethane) as sensor for electrochemical removal of aluminum and barium ions in real water samples

In this work, 5‐ferrocenyl‐dipyrromethane (Fc‐DPM) synthesized from the pyrrole and ferrocenecarboxaldehyde condensation was electrochemically deposited on a gold (Au) electrode and used to remove metal ions found in rural waters. The structural analysis of Fc‐DPM was recorded by means of nuclear magnetic resonance (NMR) techniques. The Fc‐DPM was electrochemically coated on an indium tin oxide‐polyethylene terephthalate (ITO‐PET) surface, and the resulting Fc‐DPM/ITO‐PET was characterized using scanning electron microscopy (SEM)–energy dispersive X‐ray (EDX) analysis. The heavy metal and mineral content of four real water samples from the same rural area were determined by inductively coupled plasma mass spectrometry (ICP‐MS) before and after electrochemical removal. The proposed Fc‐DPM/Au electrode was successfully applied for aluminum ion (Al3+) and barium ion (Ba2+) removal for the first time, and the limit of detection (LOD) was calculated as 0.003 and 0.217 ppb for Ba2+ and Al3+, respectively.

Carbon nanotube-grid infrared transparent electrodes for flexible electrochromic devices with visible to mid-infrared dual-band modulation

Flexible mid-infrared electrochromic devices (MIR-ECDs) have attracted wide attention due to the growing demands for thermal camouflage and body comfort. However, the normal conductive films (e.g., indium tin oxide/polyethylene terephthalate (ITO/PET) films) are unsuitable for MIR-ECDs due to low infrared transmittance. Herein, the infrared transparent carbon nanotube (CNT) grid films were prepared by designing the grid structure. The infrared transmittance of CNT grid film could reach 72 %; meanwhile, the visible transmittance could reach 75 %. The CNTs exhibited infrared modulation under different voltages due to the doping/de-doping of ions in electrolytes into the CNT network. The flexible electrochromic devices with visible to mid-infrared dual-band modulation were prepared by using CNT grid film as the electrode and poly (3,4 ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) as the electrochromic layer, which could realize the infrared synergistic modulation of PEDOT:PSS and CNT grid in the mid-infrared range and reversible color changes between light blue and dark blue in the visible range, showing promising applications in adaptive camouflage and thermal management.

Flexible urea biosensor based on CuS/Bioglass 45S5.TiO2 Nps thin films

Chronic renal insufficiency has been a high-incidence disease around the world in recent years. With the lack of devices to detect these illnesses opportunely, developing urea biosensors is imperative. This work reports the application of copper sulfide (CuS) thin films deposited via a chemical bath and Bioglass 45S5/titanium dioxide nanoparticles thin films in a urea flexible biosensor. The Bioglass 45S5 was deposited over CuS and applied onto polyethylene naphthalate (PEN) and polyethylene terephthalate (PET) with indium tin oxide (ITO) substrates. The systems PEN/CuS/Bioglass 45S5.TiO2 NpS and PET/ITO/CuS/ Bioglass 45S5.TiO2 were characterized optically by UV-Vis. The CuS presented an absorption border around 600 nm and a decrease in transmittance percentage by adding Bioglass. Scanning Electron Microscopy carried out the microstructural characterization; both systems displayed a porous morphology featuring channels suitable for immobilizing the enzyme. The sensors showed a resistive behavior based on the current-voltage curve. The urease enzyme was immobilized by adsorption. The optical changes after adding urease were measured by UV-Vis, obtaining ammonia from the reaction between urease and urea, showing an absorption border around 850 nm. Changes in urea concentrations between 1 and 10 mM caused an increase in resistivity in both samples, obtaining a sensitivity of 12.887 kΩ/sq/mM and 12.411 kΩ/sq/mM, and a linearity of 0.9946 % and 0.9601 % for the samples deposited over PEN and PET ITO, respectively. A Cole-Cole plot showed a behavior corresponding to an equivalent circuit composed of a parallel combination of a resistor and a capacitor in series with a phase constant element; this latter could be attributed to the measurement electrodes. Each sensor was implemented in a Wheatstone bridge. A voltage decrease was obtained for the sample deposited over PET ITO, with a sensitivity of −102.7 mV/mM, and a voltage increase was obtained in the sample deposited over PEN, with a sensitivity of 30.5 mV/mM.

Operando Optical Microscopy of Dead Lithium Growth in Anode‐Less Configuration

AbstractThere is an increasing demand to improve battery safety and performance as part of the global push to convert the small electronics and transportation sector to infrastructures based on electricity. This work follows the deposition of lithium metal in anode‐less conditions by an operando optical microscope using a transparent indium tin oxide‐polyethylene terephthalate (ITO‐PET) window as the current collector in a readily‐available electrochemical set‐up. The mechanism of Li metal nucleation strongly depends on the selected current densities (C/40 and 2C). After the deposition of the solid electrolyte interface (SEI), Li nucleates from mossy to needle morphology. Moreover, layer‐by‐layer growth of dead Li in voids is monitored by following its accumulation upon cycling. Dead Li deposits in residual hollow structures, especially when high current densities are applied. These optical observations are coupled with computer vision analyses to evaluate the average size of the Li deposits: smaller Li nuclei plate when high C‐rate is applied. The results here described provide insights into a new electrochemical cell concept that enables to elucidate the influence of spatial inhomogeneities of the lithophilic ITO‐PET surface on the mechanism of Li nucleation and plating.

Label-free flexible immunosensor based on nitrogen-doped graphene with titanium dioxide for the determination of depression marker dendritic cell nuclear protein-1

In this work, a label-free flexible immunosensor for selective and sensitive detection of dendritic cell nuclear protein-1 (DCNP1), a newly discovered potential marker of depression, was successfully constructed. At first, a highly conductive nanomaterial nitrogen-doped graphene with titanium dioxide (NG/TiO2) was prepared using a one-pot method, and it was used as an electrode modification material in the construction of immunosensors for the first time. NG/TiO2 was functionalized with 1-pyrene-butyric acid N-hydroxysuccinimide ester (PSE), and then the DCNP1 antibody could be better immobilized on the surface of the modified indium tin oxide-polyethylene terephthalate (ITO-PET). Then bovine serum albumin (BSA) was used to block non-specific active sites, and the immunosensor (BSA/anti-DCNP1-PSE/NG/TiO2/ITO-PET) can be obtained. The fabricated NG/TiO2 and the construction process of the immunosensor were characterized by scanning electron microscopy, infrared spectroscopy, cyclic voltammetry, and electrochemical impedance methods. Differential pulse voltammetry (DPV) was used to measure different concentrations of DCNP1 after optimizing the ratio of NG and TiO2, the modification amount of NG/TiO2, the ratio of NG/TiO2 to PSE, the concentration of anti-DCNP1 and its immobilization time, the concentration of BSA, and the incubation time of DCNP1. The constructed sensor had a wide linear range of 1 ∼ 104 pg mL−1, and a low detection limit of 0.45 pg mL−1 (S/N = 3). It had good reproducibility (RSD = 1.90 %), repeatability (RSD = 2.6 %), and selectivity. After storing it at 4 ℃ for 15 days, its performance decreased to 92.37 %. And it had been successfully used to determine DCNP1 in the brain homogenate of mice with depression induced by chronic unpredictable mild stress (CUMS), providing a possible method for the rapid and accurate determination of DCNP1.

Enhancement of the performance of a ZnO-based nanostructured flexible UV photodiode grown on the carbon clothe by piezo-phototronic effect

The current study aims to evaluate the piezo-phototronic effect on the performance of the prepared ZnO-based UV Photodiodes (PDs). To this end, the electrochemical method was employed to facilitate the growth of ZnO Nanowires (NWs) on the Carbon Clothe (CC) substrate. The results obtained from Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) analyses demonstrated well-grown ZnO NWs arrays with high coverage density and crystal quality on the substrate. The current-voltage (I–V) measurement was employed in the UV illumination and dark conditions to determine the photo-responsivity and detectivity of the prepared device to the UV light. In addition, the photocurrent and overall device performances were modified under UV illumination and applying compressive strain, given its role in increasing the barrier height. As a result, more photo-generated charge carriers can migrate to the electrode without recombination in comparison with free strain conditions. This phenomenon is known as the piezo-phototronic effect. Further, the findings of this study revealed that CC could be an appropriate alternative to the fabricated flexible PDs instead of other expensive flexible substrates such as Indium Tin Oxide/Poly-Ethylene Terephthalate (ITO/PET).

Fabrication and photocatalytic properties of Co doped ZnO nanomaterials

Co-doped ZnO nanocomposites have been prepared on polyethylene terephthalate-indium tin oxide (PET-ITO) flexible substrates using hydrothermal method. The effects of crystal structure, doping mechanism, as well as photocatalytic properties have been intensive investigated. Compared with pure ZnO, Co-ZnO has distinct photocatalytic activity with the degradation rate of 71.36% for methylene blue (MB) solution. The stable electronic structures and the possible electronic sites for Co elements in combination have been discussed with theoretical calculations. Meanwhile, the mechanism to enhance the photocatalytic activity of ZnO has been discussed.

A new ITO-based Aβ42 biosensor for early detection of Alzheimer's disease

In this study, a novel label-free impedimetric immunosensor was fabricated for rapid, selective, and sensitive quantitative analysis of Aβ42 protein for use in the diagnosis of Alzheimer's disease. The immunosensor was fabricated using inexpensive and disposable indium tin oxide polyethylene terephthalate (ITO-PET) electrodes. After the electrodes were modified with 3-glycidoxypropyldimethoxymethylsilane (GPDMMS), the antibody specific to the Aβ42 protein (anti-Aβ42) was immobilized. The affinity interaction between anti-Aβ42 and Aβ42 in the immobilization steps in immunosensor fabrication and in the quantitation of Aβ42 were analyzed using Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV) techniques. Additionally, the morphological changes occurring on the electrode surface during each immobilization step were imaged using scanning electron microscopy (SEM). The linear detection range of the immunosensor was determined as 1–100 pg/mL with the limit of detection value of 0.37 pg/mL. Analytical properties of the biosensor, including reproducibility, repeatability, storage stability, selectivity, and regeneration were investigated. The kinetic behavior of antibody-antigen complex formation was determined for the first time using single frequency impedance (SFI) analysis on an Aβ42 biosensor. The potential for use of the immunosensor in clinical studies was demonstrated by analysis of Aβ42 in commercially purchased human serum.

11-(triethoxysilyl) undecanal agent-based biosensor system using disposable ITO-PET electrode for tumour necrosis factor-alpha detection

In this study, a label-free electrochemical biosensor system based on a disposable indium tin oxide polyethylene terephthalate (ITO-PET) electrode modified with the 11-(triethoxysilyl) undecanal (11-TESU) agent was developed for the detection of tumour necrosis factor-alpha (TNF-α) in serum. The developed biosensor was observed with electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) techniques, square wave voltammetry (SWV) and single frequency impedance (SFI) technique which is utilized for the specific interaction between anti-TNF-α and TNF-α antigen. In addition, scanning electron microscopy was used to look at how the morphology of each ITO-PET surface changed (SEM). All parameters such as 11-TESU concentration, anti-TNF-α concentration and anti-TNF-α incubation time, were optimized. The biosensor system was characterized by measuring its linear determination range, repeatability, reproducibility, reusability, storage stability, and surface coverage. The TNF-αelectrochemical biosensor showed high levels of repeatability and reproducibility as well as a large dynamic range of detection (from 0.03 pg mL-1 to 3 pg mL-1). The LOD and LOQ for the biosensor were extremely low at 1x10-4 pg mL-1 and 5x10-4 pg mL-1, respectively. It was applied to real samples to determine whether the proposed biosensor would be useful in clinical settings.

Tümör Nekrozis Faktörü-alfa biyobelirteç tayini için pratik ve tek kullanımlık ITO-PET bazlı immunosensör platformu

This investigation displays a novel, practical indium tin oxide- polyethylene terephthalate (ITO-PET) based electrochemical biosensor for the Tumor Necrosis Factor-alpha (TNFα) biomarker determination. The ITO-PET electrode is a very advantageous preferred semiconductive electrode material. It has a lot of great features such as easy to prepare, cheapness, flexibility, stability. It also allows determining an analyte at very low concentrations and provides a great wide concentration range for analyte analysis. Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV) were used for the evaluation of biosensors, including the immobilization procedure, the investigation of the optimum conditions, and the characterization of biosensors. The immunosensor's electrode surface morphology during the immobilization process was observed using a Scanning Electron Microscope (SEM). In addition, Impedance measurement at a single frequency was used to characterize anti-TNFα and TNFα interactions (SFI). The clinical effectiveness of the developed biosensor was investigated by testing it with real human serum samples. Moreover, the fabricated immunosensor presents long shelf life, analysis of the antigen concentrations at picogram level (0.02 pg mL-1 -2.56 pg mL-1), reproducibility, reusability (11 times) and high sensitivity.

Langmuir-Blodgett deposition and physicochemical surface characterization of two-dimensional perovskite nanosheets on ITO-PET substrates

We successfully obtained Ca2NaNb4O13− single perovskite nanosheets by delaminating x = 4 Dion-Jacobson type KCa2NaNb4O13 layered materials. These nanosheets were then deposited onto conductive, transparent, and flexible indium tin oxide-polyethylene terephthalate (ITO-PET) substrates using the Langmuir-Blodgett (LB) technique. The polar and apolar (dispersive) surface tension components of LB nanofilms composed of Ca2NaNb4O13− perovskite nanosheets and the work of adhesion between the nanofilms and silicon and ITO-PET substrates were determined through contact angle measurements combined with mathematical modeling based on surface thermodynamics. The results showed that the apolar surface tension components had similar values for all surfaces studied, while the polar surface tension components of the nanofilms deposited on the substrates had higher values than those of the bare substrates. The higher polar interaction observed between the nanofilm and ITO-PET resulted in higher total work of adhesion of the nanofilm to the ITO-PET surface in water, while the total work of adhesion computed between the nanofilm and Si was higher in air.

Design and Simulation of Lead-free Flexible Perovskite Solar cell Using SCAPS-1D.

Despite perovskite solar cells’ rapidly increasing efficiency, industrializing and commercializing the device presents several challenges. Top among these is toxicity due to the material’s lead-based perovskite usage, which causes rapid degradation. Because of this challenge, researchers have recently become interested in lead-free perovskite materials. In this research, we investigate using the SCAPS simulation software to optimize a lead-free flexible solar cell. Lead (Pb), which belongs to group 14, can likely be replaced with bismuth (Bi), which belongs to group 15. In this study, the structure of the device is an n-i-p planar lead-free heterostructure flexible perovskite solar cell (FPSC) comprised of a Polyethylene Terephthalate/Indium Tin Oxide (PET/ITO) substrate; [6,6]-phenyl C61 butyric acid methyl ester (PCBM) Electron Transport Layer (ETL); methyl ammonium bismuth iodide (CH3NH3BiI3) as an absorber; Spiro-OMeTAD as a Hole Transport Layer (HTL); and silver (Ag) as the electrode. We optimised cell performance and efficiency with an absorber layer of 100 nm and an optimised temperature of 300 K. This absorber layer’s thickness and defect density were considered. The defect density of the FPSC is indirectly proportional to the device’s absorption coefficient (alpha). We obtained a power conversion efficiency (PCE) of 18.80%, a current density (JSC) of 35.59 mA/cm2, an open circuit voltage (VOC) of 0.633 V, and a fill factor (FF) of 83.43%. We also observed that the FF is inversely proportional to the thickness of the absorber layer of the FPSC.

Multilayer transparent bendable broadband microwave absorber covering the frequency band near 5 GHz

A multilayer transparent microwave absorber that possesses a broadband, is bendable, and covers the frequency band near 5 GHz is proposed in this work. The absorber uses three layers of 110 Ω/sq etched patterned indium–tin–oxide-polyethylene terephthalate (ITO-PET) films as the resonant layers. The infinite cycle structure of the absorber is simulated by using the CST STUDIO SUITE. The absorber shows >90% absorption effect in the frequency band 4.16-7.48 GHz and a 99% absorption effect in the band near 5 GHz (4.98-5.83 GHz). Furthermore, by replacing the intermediate medium with polydimethylsiloxane (PDMS), the absorber obtains excellent bendability characteristics.

Design of an Optically Transparent Microwave Absorber Based on Coding Metasurface

In this paper, a metamaterial absorber with a checkerboard patterned ITO (indium tin oxide) film as the surface is obtained by using flexible and optically transparent wave-absorbing material ITO–PET (polyethylene terephthalate), and a coding arrangement of two basic coding units based on the APS-PSO (Array Pattern Synthesis -Particle Swarm Optimization) algorithm. The surface structure of the absorber consists of ITO rectangular patch structures and ITO circular patch structures (110 Ω/sq). The ITO rectangular patch structures and ITO circular patch structures are symmetrical. The middle layer is made up of two layers of PET and one layer of PMMA, and the bottom surface is covered with a layer of low square resistance ITO film (8 Ω/sq). The experimental results, which are consistent with the simulation results, show that the absorber has superior performance: over 90% absorptance in the 5.06–9.01 GHz band, high transmittance, and a −10 dBsm RCS (radar cross-section) reduction in the 5.3–8.7 GHz band. This design also has polarization insensitivity and angular stability.