Hybrid organic-inorganic electrolytes via SiO2 -doping: enhanced stability and ionic conductivity for neuromorphic EGTs Bo Sun, Yifu Fu, Mohd Fakhrul Zamani Bin Abdul Kadir, Siti Nabila Aidit, Shixun Zheng, Quanjin Ma, Feiyang Li, Zhaoji Zong, Sharifah F Wan Muhamad Hatta Engineering Research Express, 2026 Hybrid organic–inorganic electrolytes represent a promising class of materials for sustainable and energy-efficient electronics, yet strategies to simultaneously improve their electrochemical robustness and functional device performance remain limited. Here, a chitosan-silica hybrid electrolyte was developed by incorporating silica nanoparticles (SiO 2 NPs, 0–2 wt%) into a chitosan matrix, and its structural, electrochemical, and dielectric properties were systematically investigated. At an optimized SiO 2 NPs content of 1.5 wt%, the hybrid electrolyte achieved an ionic conductivity of 1.83 × 10 −5 S cm −1 and a high ion transference number ( t ion = 0.909), while the swelling rate was suppressed by 160% and the breakdown voltage was enhanced to 2.76 ± 0.013 V. These improvements were attributed to increased segmental mobility and Lewis acid–base interactions that promoted ion dissociation and stabilized electric double-layer formation. To demonstrate functional relevance, the chitosan-silica hybrid electrolyte was integrated into an electrolyte-gated transistor (EGT) with zinc oxide nanoparticles (ZnO NPs) channel, yielding reproducible synaptic neuromorphic characteristics, including excitatory post-synaptic current (EPSC) of 399.32 ± 42.36 nA and a paired-pulse facilitation (PPF) index of 90.4%. Importantly, this work establishes a direct correlation between nanoscale electrolyte engineering and neuromorphic device responses, using synaptic behaviors as functional validation of electrolyte stability and ionic transport. The findings establish chitosan-silica hybrids as promising materials for next-generation neuromorphic and biocompatible electronics.
Direct functionalization of Mo2CTx MXene via single-step synthesis for printable, flexible, non-invasive moisture detection systems Syahirah Umairah Mahadi, Siti Nabila Aidit, Norazriena Yusoff, Sharifah Fatmadiana Wan Muhammad Hatta, Siti Fairus Abdul Sani Flexible and Printed Electronics, 2025 A printable moisture sensor is an advanced device designed to measure water content in various materials, including soil, air, and other substances. The incorporation of K+ functionalization significantly increases the material’s hydrophilicity, promoting more effective adsorption and desorption of water molecules. This study explores the impact of MXene functionalization on moisture sensing performance by examining the water adsorption behavior of both pure and K+-functionalized MXene-based sensors. Two different concentrations of K+-functionalized MXene, 1M and 3M, were investigated. The results demonstrated that the 3M K+-functionalized MXene exhibited better performance. These sensors demonstrated high sensitivity of 1.580 ΔR/%Δ relative humidity (RH) across a wide humidity range (20%–80% RH) and featured ultrafast response and recovery times of 2.5 s and 12.5 s, respectively. Furthermore, the Mo2CT x -based sensors not only achieve the broadest operational range but also set a new benchmark for MXene-based moisture sensor sensitivity, outperforming the current state-of-the-art. These remarkable properties establish Mo2CT x -based sensors as highly promising candidates for printable, flexible, and non-invasive moisture detection systems, enabling real-time environmental and industrial monitoring.
Generation of Stretched and Soliton Pulses from Passively Mode-Locked EDFL Utilizing Nickel-Phosphorus Trisulfide (NiPS3)-Based Saturable Absorber Nor Najwa Ismail, Rizal Ramli, Norazriena Yusoff, Siti Nabila Aidit IEEE Journal of Quantum Electronics, 2025 In this study, a nickel-phosphorus trisulfide (NiPS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub>) saturable absorber (SA) with a ~20.9% modulation depth was used for mode-locking in an erbium-doped fiber laser (EDFL) operating in near-zero and anomalous dispersion regimes. The SA was formed by depositing a layer of NiPS<sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> material onto an arc-shaped fiber. The pulses generated were initially observed in the stretched pulse regime. Then, an 84 m long single-mode fiber (SMF) was added to the cavity to operate in the anomalous dispersion regime. The center wavelength of the pulses was observed at 1566.6 nm and 1561.6 nm for the stretched and anomalous dispersion regimes, respectively, with measured 3-dB bandwidths of 3.2 nm and 1.4 nm. The corresponding repetition rates were 6.6 MHz and 1.8 MHz, while the pulse widths with Gaussian and sech<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> profiles were 1.53 ps and 2.26 ps. Stable mode-locking operation was obtained with a signal-to-noise ratios (SNRs) of ~66 dB and ~49 dB for the pulses at the stretched and soliton regimes. The findings of this work can contribute towards the optimization of mode-locked fiber laser cavity designs for the C-band wavelength region.
Modeling and Simulation of Percolation Transition in PDMS:CB Conductive Composites Using Effective Medium and Resistor Network Approaches Fu Yifu, Siti Nabila Binti Aidit, Wan Nor Liza Binti Wan Mahadi, Zhang Shihao, Peng Yilin, Hanim Hussin, Norhayati Soin, Sharifah Fatmadiana Wan Muhamad Hatta IEEE Regional Symposium on Micro and Nanoelectronics Rsm, 2025 This study investigates the numerical simulation of the electrical conductivity of polydimethylsiloxane (PDMS) filled with carbon black (CB) to explore the percolation transition range. A discretized model of a PDMS:CB composite film is constructed, and key parameters, including the mass ratio-based modified volume fraction, the probability of tunneling conduction, and nanoparticle contact, are calculated for each microelement. These parameters are incorporated into the Bruggeman effective medium approximation to determine the local conductance. A two-dimensional (2D) resistor network is established based on the conductance matrix, with defined boundary conditions. MATLAB simulations are employed to analyze the electric potential distribution and current density under varying mass fractions and dispersion homogeneity. The results illustrate the transition range of percolation, which begins at a filling mass ratio of approximately 0.03 and extends up to 0.25 for the nanoparticle (CB) with 25 nm diameter, also shows out a clear lag or rightward movement of percolation as the diameter of particle increased. And a good match in the post part of percolation threshold area and bulk conductive area compared with the measured data in reference. And the distribution of current and voltage under different particle dispersion homogeneities governed by standard deviations of 0.05, 0.1, 0.15, and 0.2 in a normal distribution are discussed for the influence of conductivity. The results demonstrate the correlation between CB concentration and conductivity under different dispersion states, plotted on both linear and exponential scales. Three distinct phases are observed: a slight increase phase, a sharp rising phase, and a saturation phase. These findings provide valuable insights for optimizing conductive polymer composites for advanced electronic applications.
Development of Screen-Printed Biodegradable Flexible Organic Electrochemical Transistors Enabled by Poly(3,4-ethylenedioxythiophene) Polystyrene Sulfonate and a Solid-State Chitosan Polymer Electrolyte Bo Sun, Sharifah F. Wan Muhamad Hatta, Norhayati Soin, Mohd Fakhrul Zamani Bin Abdul Kadir, Fazliyatul Azwa Md Rezali, Siti Nabila Aidit, Li Ya Ma, Quanjin Ma ACS Applied Electronic Materials, 2024 Organic electrochemical transistors (OECTs) are gaining interest for applications in neuromorphic devices and biosensors. Traditional OECTs use aqueous or ionic gel electrolytes, but these materials often limit performance and wider application due to their fluid nature and poor biocompatibility. This study introduces a biodegradable, flexible solid-state OECT using a chitosan biopolymer electrolyte. The electrolyte consists of chitosan, dextran, and lithium perchlorate (LiClO 4 )-based salt. The chitosan-based OECTs feature an organic poly(3,4-ethylenedioxythiophene) polystyrene sulfonate semiconductor channel and are fabricated using screen printing. They demonstrate impressive performance, including an on-state current of 0.19 ± 0.03 mA at a low 0.6 V bias voltage, a high on/off current ratio of 0.3 × 10 3, and a large transconductance of 0.416 ± 0.05 mS. Additionally, these OECTs show remarkable endurance and mechanical robustness, maintaining stability after 300 bending cycles, long-term bending, and under temperatures ranging from 30 to 75 °C. Significantly, the chitosan-based OECTs are biodegradable, breaking down without toxic byproducts and reducing environmental impact. This makes them a promising option for future bioelectronics and wearable technology that leverage natural biomaterials.
Hydrothermal synthesis of zinc oxide/PEDOT:PSS composite for flexible temperature sensor application S N Aidit, F A M Rezali, N H M Nor, N Yusoff, Li-Ya Ma, S F W M Hatta, N Soin Flexible and Printed Electronics, 2023 A flexible and printable temperature sensor was proposed for a fast detection of temperature measurements. A hybrid composite of zinc oxide (ZnO) and a conductive polymer poly(3,4-ethylenedioxythiophene):poly(styrenesulfonicacid) (PEDOT:PSS) was utilized as the temperature-sensing layer. An interdigitated electrodes structure based on silver (Ag) ink was used to electrically connect the composite through a facile drop-casting technique. A standout aspect of this work is the presentation of ZnO/PEDOT:PSS as a temperature-sensing layer. The PEDOT:PSS flakes were connected by hydrothermally prepared ZnO nanorods, which increased the composite sheets’ electrical conductivity. The linearity, sensitivity, stability and dynamic response of the flexible sensor were examined from a temperature of 29 °C–60 °C. The sensor has high sensitivity of 1.06% °C−1 with response and recovery times of 5 s and 12.7 s, respectively. This work clearly demonstrates the potential of ZnO/PEDOT:PSS composite for flexible temperature sensor and adds to the rapidly expanding field of personalized mobile healthcare.
Fabrication of Flexible and Printable Organic Thin-Film Transistor-based Sensor Fazliyatul Azwa Md Rezali, Norhayati Soin, Sharifah Fatmadiana Wan Muhamad Hatta, Siti Nabila Aidit Proceedings 2023 IEEE Regional Symposium on Micro and Nanoelectronics Rsm 2023, 2023 As the next generation technology, organic thin-film transistor (OTFT) is fully desired in manufacturing flexible electronics due to its’ mechanically strong property and low-temperature processing at large-scale production. In this work, OTFT device using poly(3,4-ethylene dioxythiophene) polystyrene sulfonate (PEDOT:PSS) is successfully fabricated on a flexible film by screen printing and drop casting technique at maximum process temperature of 80 °C. A For such straightforward deposition techniques, the device demonstrated a potentially good reproducibility and repeatability. Moreover, a significant property is observed on the device’s current-voltage (I-V) performance that shows the average output source current is larger by ~4.4 times at maximum when dielectric reduce from ~24.04 µm to ~13.87 µm. The implementation of extended gate and reference electrode further enable detection in phosphate buffered saline (PBS) with small hysteresis. Eventually, the flexibility and printability of the fabricated OTFT raised the opportunity of low-cost application such as disposable biosensor to detect specific analyte at a small volume of solution.
