The porous materials of SnO 2 @NGO composite was synthesized by thermal reduction process at 550 °C in presence ammonia and urea as catalyst. In this process, the higher electrostatic attraction between the SnO 2 @NGO nanoparticles were anchored via thermal reduction reaction. These synthesized SnO 2 @ NGO composites were confirmed by Raman, XRD, XPS, HR-TEM, and EDX results. The SnO 2 nanoparticles were anchored in the NGO composite in the controlled nanometer scale proved by FE-TEM and BET analysis. The SnO 2 @NGO composite was used to study the electrochemical properties of CV, GCD, and EIS analysis for supercapacitor application. The electrochemical properties of SnO 2 @NGO exhibited the specific capacitance (~378 F/g at a current density of 4 A/g) and increasing the cycle stability up to 5000 cycles. Therefore, the electrochemical results of SnO 2 @NGO composite could be promising for high-performance supercapacitor applications.

A flexible and cost-effective electromechanical device for tactile sensing based on ZnO nanorods (ZnO NRs) grown on fabrics is developed. Sensing performance and the electromechanical properties of ethylcellulose/polyurethane-coated ZnO NRs on fabric substrates were tested by the LCR meter, force transducer, vibrator, and pulse analyzer. The peak-to-peak output voltage at an applied force of 21.5 N dropped considerably for the wool-, nylon-, and PP substrates and reached to the order of 3.84 mV, 1.8 mV and 4.1 mV, respectively. Furthermore, the frequency dependency of the dissipation factors revealed abrupt changes at low frequencies, while these changes were negligible at high frequencies.

Planar-type resistance temperature detectors (P-RTDs) were fabricated via fused deposition modeling by dual nozzle extrusion. The temperature-sensing element of the fabricated sensor was printed with electrically conductive polylactic acid/carbon black (PLA/CB) composite, while the structural support was printed with a PLA insulator. The temperature-dependent resistivity change of PLA/CB was evaluated for different stacking sequences of PLA/CB layers printed with [0°/0°], [−45°/45°], and [0°/90°] plies. Compared to a PLA/CB filament used as 3D printing source material, the laminated structures exhibited a response over 3 times higher, showing a resistivity change from −10 to 40 Ω∙cm between −15 and 50 °C. Then, using the [0°/90°] plies stacking sequence, a P-RTD thermometer was fabricated in conjunction with a Wheatstone bridge circuit for temperature readouts. The P-RTD yielded a temperature coefficient of resistance of 6.62 %/°C with high stability over repeated cycles. Fabrication scalability was demonstrated by realizing a 3 × 3 array of P-RTDs, allowing the temperature profile detection of the surface in contact with heat sources.

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The mechanical, thermal, optical, electrical and morphological properties of cellulose, an excellent natural biomaterial, can be improved by organic-inorganic hybrid composite methods. Based on the pristine properties of cellulose, the preparation of cellulose-metal oxide hybrid nanocomposites using a dispersion process of nanoparticles into the cellulose host matrix by traditional methods, has limitations. Recently, the functionalized cellulose-polymer-based materials were considered to be an important class of high-performance materials, providing the synthesis of various functional hybrid nanocomposites using a sol-gel method. Transparent cellulose-POSS-amine-silica/titania hybrids were prepared by an in-situ sol-gel process in the presence of γ-aminopropyltrimethoxylsilane (γ-APTES). The methodology involves the formation of covalent bonding between the cellulose-POSS amine and SiO2/TiO2 hybrid nanocomposite material. An analysis of the synthesized hybrid material by Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, differential thermal calorimetry, scanning electron microscopy, and transmission electron microscopy indicated that the silica/titania nanoparticles were bonded covalently and dispersed uniformly into the cellulose-POSS amine matrix. In addition, biological properties of the cellulose-POSS-silica/titania hybrid material were examined using an antimicrobial test against pathogenic bacteria, such as Bacillus cereus (F481072) and E. coli (ATCC35150) for the bacterial effect.