Solution Processing Techniques Research Articles

Oxide electronics: Translating materials science from lab-to-fab

Advances in the science and technology of thin-film materials have fueled a myriad of developments in large area electronics. This is particularly true for amorphous oxide semiconductors. Oxides have underpinned a number of technologically significant innovations in displays, sensors, and photovoltaics. Now they are setting the stage for exciting new applications related to flexible electronics and three-dimensional (3D) integration for post-complementary metal oxide semiconductor (CMOS) back-end-of-line processing in the quest for more-than-Moore solutions. This article reviews the development of oxide semiconductors and associated integration processes that have translated materials science fiction to commercial reality on a large scale. These advances have been driven by a host of advantages such as low cost, prudent manufacturing and large area scalability. What makes oxide semiconductors so attractive? These materials have a wide bandgap, which provides for high transparency; a cool feature for seamless embedding of electronics, particularly displays and imagers, for the immersive ambient. The OFF-current in oxide thin-film transistors is ultralow, thanks to the very low density of states in the bandgap. Indeed, this attribute is indispensable to minimize charge leakage in switching transistors and for low power, low-voltage, high-resolution sensor interfaces. More importantly, oxide thin-film transistors can be processed at relatively low temperatures thus making them amenable for 3D integration on post-processed CMOS silicon. This article provides the current status of the oxide semiconductor technology. We review the evolution of oxides based on their functional properties, along with deposition and solution processing techniques for heterostructure thin-film transistors, phototransistors, nanowire image sensors, ultralow power Schottky-barrier transistors, and 3D integration for back-end-of-line CMOS. These devices constitute fundamental building blocks for a new generation of applications ranging from interactive displays and imaging to future 3D electronic systems that are not constrained by form factor.Graphical abstract

Design and implementation of an inverter and its application in ring oscillator circuits using an organic-thin-film-transistor based on an FTM-derived channel

The organic thin film transistor (OTFT) has evolved in a big way, eventually replacing inorganic-based solid-state devices. An extensive survey of the literature reveals that the full potential of OTFTs has neither been explored nor exploited for circuit-level implementation for logic circuit design, despite the popularity of these devices. We have fabricated a PBTTT-C14 (poly (2,5-bis (3-tetradecylthiophen 2yl) thieno (3,2b) thiophene)) based OTFT by using a low-cost solution-processable technique via the floating transfer method (FTM). The fabricated OTFT using FTM shows better electrical behavior than its counterpart fabricated by using the conventional solution-processable technique. The superior electrical characteristics of the FTM-derived devices prompted us to develop a compact model of the p-channel OTFT. The compact modeling results of OTFT show a reasonably good agreement with our experimental results. We have also designed and implemented a PBTTT-C14 OTFT-based inverter circuit and ring oscillator circuit to explore the future of organic-based integrated circuits.

Photodeposited Polyamorphous CuOx Hole-Transport Layers in Organic Photovoltaics

Hole-selective charge-transport layers are an important part of modern thin-film electronics, serving to direct electron flow and prevent leakage current. Crystalline metal-oxide hole-transport layers (HTLs) such as NiO and CuOx exhibit high performance and stability. However, they are traditionally not amenable to scalable and sustainable solution-processing techniques. Conversely, amorphous metal oxides are much more readily prepared by low-temperature solution processing methods but often lack the charge-transport properties of crystalline semiconductors. Herein, we report the fabrication of amorphous a-CuOx thin films from commercially available starting materials using a simple UV-based thin-film deposition method. Subsequent thermal annealing of the a-CuOx induces an amorphous-to-amorphous phase transition, resulting in p-type semiconducting behavior. The resulting thin films were used as HTLs in organic photovoltaic devices with power conversion efficiencies comparable to those fabricated with PEDOT:PSS.

Electrical and mechanical properties of flexible multiwalled carbon nanotube/poly (dimethylsiloxane) based nanocomposite sheets

In this study, the development of highly flexible polymer nanocomposite sheets using multi-walled carbon nanotube (MWCNT) in a poly (dimethylsiloxane) (PDMS) matrix has been presented. Solution processing technique was employed, and MWCNTs were dispersed in n-hexane, and PDMS is resulting in a homogenous dispersion (between 2 wt% and 10 wt%). Scanning electron micrograph (SEM) images show the distribution of MWCNTs within PDMS matrix, which form continuous conductive networks resulting in percolation threshold even at 2 wt% filler concentrations. The electrical conductivity of the fabricated nanocomposite sheets was found to be about 1.3–158.2 S/m. Samples with 2 wt% and 4 wt% filler concentrations exhibit excellent temporal stability both in ambient and vacuum conditions, with near-zero temperature coefficient of resistance. The nanocomposite sheets used for mechanical studies were made as per ASTM D-412-C standards. For an optimal filler concentration of 5.58 wt% can be observed with stiffness of 0.486 MPa, the tensile strength of 0.422 MPa, the electrical conductivity of about 39.5 S/m, and elongation up to 120%. Therefore, this filler concentration is most suited for fabricating flexible strain sensors with good conductivity and temporal stability.

Antisolvent-Processed One-Dimensional Ternary Rubidium Copper Bromine Microwires for Sensitive and Flexible Ultraviolet Photodetectors.

Recently, newly emerging halide perovskites have aroused intensive attention in photoelectric fields in virtue of their good properties, such as well-balanced carrier transport, large light absorption coefficient, tunable band gap, and low-temperature solution processing technique. Nevertheless, their future commercial development is severely hampered by lead toxicity and instability of such materials. In this work, one-dimensional Rb2CuBr3 single-crystal microwires (MWs) were prepared by antisolvent engineering, and they were further employed as absorbers to prepare sensitive ultraviolet (UV) photodetectors. The optical band gap of Rb2CuBr3 MWs is measured to be 3.83 eV, exhibiting an excellent UV absorption. The fabricated device demonstrates a remarkable UV light detection ability with a specific detectivity of 1.23 × 1011 Jones, responsivity of 113.64 mA W-1, and response speed of 69.31/87.55 ms under light illumination of 265 nm. Meanwhile, the proposed photodetector without any encapsulation shows outstanding stability and repeatability. After storing in ambient air for 2 weeks, the light detection ability remains basically unchanged. Further, a flexible photodetector was fabricated with the same structure, which demonstrates a remarkable bending endurance. These results confirm the great potential of Rb2CuBr3 for high-performance UV photodetectors, increasing the possibility for assembly of optoelectronic systems.

High Response of Ethanol Gas Sensor Based on NiO-Doped Apple Pectin by the Solution Process

Novel gas sensor devices, based on biomaterial apple pectin film (APN) doped with NiO, were fabricated for the first time using a solution processing technique. The device was then annealed in a microwave chamber. The structural, elemental, and surface morphology of the device was investigated, using TEM, XPS, and AFM, respectively. The as-fabricated film sensor possessed a superior sensing performance regarding ethanol gas, compared to the pure apple pectin film sensor. The response of the device was recorded at a maximum efficiency of 161. For a 10 ppm concentration of ethanol gas at an operational temperature of 250 °C, the response time was 1.379 s. Nevertheless, the sensing mechanism for the sensor device is also described thoroughly.

Optimization of carrier transport layer: A simple but effective approach toward achieving high efficiency all-solution processed InP quantum dot light emitting diodes

High performance quantum dot light emitting diodes (QD-LED) are being considered as a next-generation technology for energy efficient solid-state lighting and displays. In recent years, cadmium (Cd)-based QLEDs have made great progress in performance, which is close to commercial applications. However, the performance of environmentally friendly Cd-free QD-LED still needs to be improved. In this letter, using InP/ZnS quantum dots (QDs), an environmentally friendly red QDs material, as the light emitting layer, low-cost all-solution processed red InP/ZnS QD-LED are fabricated. The optimized device with a hybrid multilayered structure employing an organic double hole transport layer (HTL) with doping small molecules (TFB/PVK:TAPC) and an inorganic ZnMgO nanoparticles (NPs) electron transport layer (ETL), here TFB, PVK and TAPC represent poly [(9,9-dioctylfluorenyl-2,7-diyl)- co -(4,4’-( N -( p -butylphenyl))-diphenylamine)], poly (9-vinlycarbazole) and 1,1-bis [4-[N,N′-di ( p -tolyl)amino]phenyl]-cyclohexane, respectively. The best device exhibits a peak current efficiency (CE) of 7.58 cd A −1 , which is 2.4 times higher than the control device using PVK (HTL) and ZnO (ETL). At the same time, turn-on voltage dropped from 2.8 V (control devices) to 2.4 V. These superb QD-LED performances originate not only from the improved hole injection by the introduction of a double hole layer and the reduced the quenching of excitons by using ZnMgO NPs ETL but also from increasing the hole mobility with doping of small molecule materials in PVK to balance the carrier transportation. This work provides a simple and feasible idea with optimization the carrier transport for realizing high-efficiency QD-LED devices. • For the first time, systematically optimizing both HTL and ETL in InP-based red QD-LED, which is simple but effective. • A double layer of TFB/PVK HTLs are introduced, and doping TAPC with high hole mobility into PVK. • Device with peak CE of 7.58 cd A −1 was obtained, which total nearly 140% improvement compare with control device. • All solution-process technique can reduce fabrication cost.

Ni2+ enriched carbon nanotubes nanohybrids based non-platinum counter electrodes for dye sensitized solar cells

The development of competent substitutes for Pt counter electrode (CE), possessing excellent electrocatalytic activity, stability, and ready availability, is a key issue to materialize the long-term stability and economical large-scale industrial production of future generation dye sensitized solar cells (DSSCs). In the present work, a cost effective and solution processable hydrothermal technique has been utilized to synthesize Ni2+ enriched nanohybrids of nickel oxide (NiO) and nickel sulfide (Ni3S2) nanoparticles with multi-walled carbon nanotubes (MWCNTs) as CE in DSSCs. NiO/MWCNTs nanohybrids showed superior electrocatalytic behaviour among MWCNTs, NiO, Ni3S2, nanohybrids, and Pt. The nanohybrids containing aligned network MWCNTs exhibited good electrical conductivity, high specific surface area and better stability. These nanohybrids have been further employed as CE in DSSCs and observed higher Power Conversion Efficiency (PCE) for NiO/MWCNTs nanohybrids CE (3.80%) among others and is almost comparable to that of Pt based DSSC (3.90%). It has been explained on the basis of Ni2+content present in the nanohybrids. The higher content of Ni2+species provides a greater number of active sites representing higher electrocatalytic activity that would further productively catalyze the reactions occurring at CE/electrolyte interface in DSSCs.

Temperature dependence of MAPbI3 films by quasi-vapor deposition technique and impact on photovoltaic performance and stability of perovskite solar cells

Perovskite solar cells (PSC) have been a major focus in the photovoltaic community because of their high efficiency within a decade. The performance and stability of PSCs are highly dependent on the perovskite layer deposition and film quality. However, the solution processing techniques are still lacking to produce high-quality perovskite films for large scale device fabrication. In this work, a high-quality and uniform MAPbI3 perovskite films are developed by quasi-vapor deposition (QVD) at low temperature, low working pressure, with short reaction time and without post annealing. The substrate temperature is varied from 70 °C to 130 °C during the deposition in order to study the film uniformity, morphology and its influence on PSCs. MAPbI3 films deposited at 100 °C showed uniform film with grain size of 375 nm and the PSCs prepared with the film exhibited the highest power conversion efficiency (PCE) of 15.6%. Simultaneously, PSC prepared with the solution process exhibited PCE of 12.0% with poor ambient stability than the QVD processed devices. The results will provide a new pathway for developing high quality and large scale device with high performance and stability.

Efficient and large-area all vacuum-deposited perovskite light-emitting diodes via spatial confinement

With rapid advances of perovskite light-emitting diodes (PeLEDs), the large-scale fabrication of patterned PeLEDs towards display panels is of increasing importance. However, most state-of-the-art PeLEDs are fabricated by solution-processed techniques, which are difficult to simultaneously achieve high-resolution pixels and large-scale production. To this end, we construct efficient CsPbBr3 PeLEDs employing a vacuum deposition technique, which has been demonstrated as the most successful route for commercial organic LED displays. By carefully controlling the strength of the spatial confinement in CsPbBr3 film, its radiative recombination is greatly enhanced while the nonradiative recombination is suppressed. As a result, the external quantum efficiency (EQE) of thermally evaporated PeLED reaches 8.0%, a record for vacuum processed PeLEDs. Benefitting from the excellent uniformity and scalability of the thermal evaporation, we demonstrate PeLED with a functional area up to 40.2 cm2 and a peak EQE of 7.1%, representing one of the most efficient large-area PeLEDs. We further achieve high-resolution patterned perovskite film with 100 μm pixels using fine metal masks, laying the foundation for potential display applications. We believe the strategy of confinement strength regulation in thermally evaporated perovskites provides an effective way to process high-efficiency and large-area PeLEDs towards commercial display panels.

Large-area patterning of full-color quantum dot arrays beyond 1000 pixels per inch by selective electrophoretic deposition

Colloidal quantum dot (QD) emitters show great promise in the development of next-generation displays. Although various solution-processed techniques have been developed for nanomaterials, high-resolution and uniform patterning technology amicable to manufacturing is still missing. Here, we present large-area, high-resolution, full-color QD patterning utilizing a selective electrophoretic deposition (SEPD) technique. This technique utilizes photolithography combined with SEPD to achieve uniform and fast fabrication, low-cost QD patterning in large-area beyond 1,000 pixels-per-inch. The QD patterns only deposited on selective electrodes with precisely controlled thickness in a large range, which could cater for various optoelectronic devices. The adjustable surface morphology, packing density and refractive index of QD films enable higher efficiency compared to conventional solution-processed methods. We further demonstrate the versatility of our approach to integrate various QDs into large-area arrays of full-color emitting pixels and QLEDs with good performance. The results suggest a manufacture-viable technology for commercialization of QD-based displays.

Radiation polymerized CsPbBr3-PMMA nanocomposite for alpha particle detection

Inorganic perovskite nanocrystals demonstrate tremendous optoelectronic properties and can be synthesized by various solution-processing techniques but they are largely overlooked for their alpha radiation scintillation applications. Synthesis of these perovskites from constituent solution and their efficient dispersion into matrix phase is still challenging. Here we demonstrate a simple, low-cost, in-situ strategy to fabricate CsPbBr3 – PMMA nanocomposite films through catalyst-free gamma irradiation and their room temperature alpha-scintillation response. Perovskite nanocrystals with average particle size of 43 nm were successfully prepared through the supersaturated recrystallization technique. Gamma-radiation-induced polymerization successfully yielded translucent yellow color nanocomposite films. Their optical properties were evaluated using UV–Vis absorbance and Photoluminescence (PL) spectroscopy. We report for the first time, facile development and preliminary alpha response of solution processable - γ radiation polymerized CsPbBr3 - PMMA based nanocomposite for plastic scintillation.

Solvent Engineering for Controlled Crystallization and Growth of All-Inorganic Pb-Free Rudorffite Absorbers of Perovskite Solar Cells.

Solution-processed Ag-Bi-I rudorffites with direct band gaps of <2 eV show promise for highly efficient and cost-effective Pb-free solar cells. However, relatively fast crystallization rates of Bi-based films and limited solubility of BiI3 in many solvents result in poor film morphologies, inhibiting their device performance. Here, we conduct a solvent-engineering method to adjust the dynamics of nucleation and growth during film formation. We fabricate Ag2BiI5, AgBiI4, and AgBi2I7 absorber layers using a mixed solvent of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) and find that a volume percentage of 50% DMSO causes highly uniform and dense perovskite films via a BiI3-DMSO-AgI intermediate phase formation, leading to solar cells with an improved power conversion efficiency of 0.62% for the Ag2BiI5 absorber. These results provide valuable insights into the optimization of the solution processing technique to realize low-toxicity and efficient perovskite solar cells.

A Rapidly Stabilizing Water-Gated Field-Effect Transistor Based on Printed Single-Walled Carbon Nanotubes for Biosensing Applications.

Biosensors are expected to revolutionize disease management through provision of low-cost diagnostic platforms for molecular and pathogenic detection with high sensitivity and short response time. In this context, there has been an ever-increasing interest in using electrolyte-gated field-effect transistors (EG-FETs) for biosensing applications owing to their expanding potential of being employed for label-free detection of a broad range of biomarkers with high selectivity and sensitivity while operating at sub-volt working potentials. Although organic semiconductors have been widely utilized as the channel in EG-FETs, primarily due to their compatibility with cost-effective low-temperature solution-processing fabrication techniques, alternative carbon-based platforms have the potential to provide similar advantages with improved electronic performances. Here, we propose the use of inkjet-printed polymer-wrapped monochiral single-walled carbon nanotubes (s-SWCNTs) for the channel of EG-FETs in an aqueous environment. In particular, we show that our EG-CNTFETs require only an hour of stabilization before producing a highly stable response suitable for biosensing, with a drastic time reduction with respect to the most exploited organic semiconductor for biosensors. As a proof-of-principle, we successfully employed our water-gated device to detect the well-known biotin–streptavidin binding event.

Energy-Level Manipulation in Novel Indacenodithiophene-Based Donor–Acceptor Polymers for Near-Infrared Organic Photodetectors

Organic photodetectors (OPDs) are promising candidates for next-generation digital imaging and wearable sensors due to their low cost, tuneable optoelectrical properties combined with high-level performance, and solution-processed fabrication techniques. However, OPD detection is often limited to shorter wavelengths, whereas photodetection in the near-infrared (NIR) region is increasingly being required for wearable electronics and medical device applications. NIR sensing suffers from low responsivity and high dark currents. A common approach to enhance NIR photon detection is lowering the optical band gap via donor-acceptor (D-A) molecular engineering. Herein, we present the synthesis of two novel indacenodithiophene (IDT)-based D-A conjugated polymers, namely, PDPPy-IT and PSNT-IT via palladium-catalyzed Stille coupling reactions. These novel polymers exhibit optical band gaps of 1.81 and 1.27 eV for PDPPy-IT and PSNT-IT, respectively, with highly desirable visible and NIR light detection through energy-level manipulation. Moreover, excellent materials' solubility and thin-film processability allow easy incorporation of these polymers as an active layer into OPDs for light detection. In the case of PSNT-IT devices, a photodetection up to 1000 nm is demonstrated with a peak sensitivity centered at 875 nm, whereas PDPPy-IT devices are efficient in detecting the visible spectrum with the highest sensitivity at 660 nm. Overall, both OPDs exhibit spectral responsivities up to 0.11 A W-1 and dark currents in the nA cm-2 range. With linear dynamic ranges exceeding 140 dB and fast response times recorded below 100 μs, the use of novel IDT-based polymers in OPDs shows great potential for wearable optoelectronics.

Molecular Design of Luminescent Gold(III) Emitters as Thermally Evaporable and Solution-Processable Organic Light-Emitting Device (OLED) Materials.

The advancement of high-efficiency luminescent and thermally stable organometallic complexes has offered opportunities for the commercialization of metal phosphors for fabricating organic light-emitting devices (OLEDs). Since the first report on the potential use of iridium(III) and platinum(II) complexes for applications in OLEDs in the late 1990s, extensive efforts have been made by researchers on the development of various heavy metal-containing compounds with rich photophysical and luminescence properties and the engineering of device architectures to improve device efficiencies. Apart from the more well-studied iridium(III) and platinum(II) complexes, complexes of gold(III) recently have demonstrated their capabilities to serve as phosphorescent or thermally stimulated delayed phosphorescent or thermally activated delayed fluorescent emitters, and their promising performances in OLEDs have attracted growing interest in the past decade. Nowadays, complexes of gold(III) with emission energies ranging from sky-blue to near-infrared with high electroluminescence performances have been obtained. In addition, high-efficiency vacuum-deposited and solution-processed OLEDs with benchmark efficiencies comparable to those of the iridium(III) and platinum(II) complexes have been realized. This Focus Review summarizes the development of various series of luminescent gold(III) complexes to date and highlights important milestones in the development and advancement of gold(III)-based OLEDs. Focus will be made on the molecular design strategies for gold(III) emitters for application as dopants in OLEDs, including those fabricated by vacuum-deposition and solution-processing techniques.

Ultrasensitive self-powered UV photodetector based on a novel p-n heterojunction of solution-processable organic semiconductors

This work reports a highly sensitive self-powered ultraviolet photodetector, which is based on the active layer of NPD:Alq3 with different Alq3 contents. All solution-processed technique was utilized to fabricate the active layers of the devices to achieve an optimized system that exhibits highly sensitive and stable photodetector under self-powered operation mode. The values of photosensitivity, responsivity, and detectivity of the photodiodes at zero-bias were estimated at 1.30 × 105, 1.07 mA/W, 1.04 × 1011 Jones, respectively. The rise and decay times of the optimized device were estimated at 0.34 s and 0.28 s, respectively. For practical application of the device sensing efficiency, the optimal load line of self-powered UV photodetector to deliver the maximum power was estimated of an internal impedence of 0.579 MΩ. In conclusion, the high sensitivity, good stability, and fast response/recovery speed of the self-powered UV photodetector make the devices applicable to resolve some of the current issues in UV detection.

Photo-patterned oxide films produced using polymeric metal acrylate for low-voltage thin-film transistors

Solution-processed zinc oxide (ZnO) thin-film transistors (TFTs) have received considerable attention as key elements for future electronics due to the ease of fabricating these TFTs and due to the natural abundance and hence low cost of ZnO. However, issues regarding the patterning of solution-processed ZnO semiconductor films unfortunately continue to pose a barrier to their commercialization. In this study, we optimized nanometer-thick photo-curable zinc acrylate (ZnA) films as ZnO precursors and used these precursors to prepare photo-patterned ZnO semiconductors for the fabrication of n-type TFTs. Solution-processed ZnA films were effectively micro-patterned under UV light, because UV-irradiated ZnA film was not solved in etching solvent as a result of photocrosslinking of diacrylate moiety. Through a sol-gel reaction, wurtzite ZnO crystals were stably formed from the photo-patterned ZnA films. After optimizing the film thickness and by using a photo-patterned ZrOx dielectric layer, the prepared ZnO TFT exhibited stable performances with a low-voltage operation within ±2 V. This approach for developing a ZnO semiconductor film can be used to enable the realization of simple, inexpensive, and environmentally friendly solution-processing techniques in electronic device fields.

Flexible and Transparent Agnws-Based Microelectrode Arrays and Interconnects for Multifunctional Electrical and Optical Biointerfacing

Transparent microelectrode provides a promising approach combining electrophysiology and optogenetics for multi-functional biointerfacing. Flexible platforms with high performance which can achieve seamlessly integrating with soft tissue systems are highly needed. Herein, we demonstrate silver nanowires (Ag NWs)-based transparent microelectrode arrays (MEAs) and interconnects to meet this demand by using an innovative photolithography-based solution-processing technique. The resulting microelectrodes exhibit a high transparency of 76.1-90.0% over the visible spectrum, and low normalized electrochemical impedance of 3.4-15 Ω cm2 at 1 kHz which is comparable to that of opaque solid Ag films (12.4 Ω cm2). 93% transparency at 550 nm can be achieved through patterning the nanowire networks. Additionally, the microelectrodes possess excellent sheet resistance of 11-25 Ω sq−1, superior mechanical stability for 100,000 bending cycles at 5 mm radius, and chemical stability after 30-day soaking at 37 oC. In vivo histology study reveals the biocompatibility of the device. Studies on rat and transgenic mouse hearts show the ability of Ag NWs MEAs to optical mapping with negligible light-induced artifacts and real-time monitoring of heart rhythm under simultaneously optogenetic pacing with high-fidelity, respectively. This work illustrates that the Ag NWs-based platform can serve as a promising candidate for the next-generation of large-scale multi-functional biointerfaces for biological and biomedical research. Figure 1

Facile Synthesis and Characterizations of Silver Nanoparticles-Reduced Graphene Oxide Hybrid

Here, we report the synthesis of silver nanoparticles-reduced graphene oxide (AgNPs-rGO) hybrid for simple and eco-friendly method. Silver nanoparticles (AgNPs) were successfully deposited on reduced graphene oxide (rGO) sheets to form (AgNPs-rGO) hybrid using lemon extract as a reducing and stabilizing agent. The products form a stable aqueous solution without any surfactant stabilizers and this makes it possible to produce (AgNPs-rGO) hybrid on a large scale using low-cost solution processing technique. The synthesis of nanohybrid was examed at different ratio of reducing agent (1:1, 1:2, 1:4) and characterized using UV-Visible (UV-Vis) absorption spectrum, X-ray diffraction (XRD), Raman spectroscopy analyses and transmission electron microscopy (TEM) analyses. From UV-Vis absorption spectrum, the (AgNPs-rGO) (1:1) hybrid result shows the sharp peak at 433 nm indicating the accomplishment formation of AgNPs on the surface of rGO sheets. Crystalline and spherical AgNPs with an average particle size of 21 nm were found in the (AgNPs-rGO) hybrid with the assistance of 1:1 reducing agent. Furthermore, (AgNPs-rGO) (1:1) hybrid exhibit fast electron-transfer kinetics for electrochemical reaction of Fe (CN)63-/4- redox couple compared to other controlled modified electrodes, suggesting the potential applications for electrocatalysis and electrochemical sensor.