RESUMEN
In this study, a PANI/NiO/Graphene (PNG) nanocomposite was synthesized using a cost-effective wet chemical polymerization method. This nanocomposite was used to fabricate supercapacitor electrodes in a nontoxic, noncorrosive, and neutral hybrid gel polymer (PVA/Na2SO4) electrolyte. The electrodes made from the PNG material underwent analysis using electrochemical techniques, including cyclic voltammetry (CV) and electrochemical impedance spectroscopy in a three-electrode system. For a deeper exploration of the supercapacitive properties of the PNG material, galvanostatic charge-discharge was employed. A practical two-electrode symmetric device powered by the hybrid PVA/Na2SO4 electrolyte was fabricated to calculate specific capacitance, energy density, and power density. The designed PNG material demonstrates excellent electrochemical behavior, exhibiting an improved energy density of 59.41 W h/kg at 850 W/kg. Furthermore, the PNG electrode shows excellent reversibility along with enhanced energy density and retains 89% of its capacitance after 2000 cycles. These outstanding properties of the PNG material can be attributed to the synergistic effect of PANI nanofibrous, NiO, and graphene two-dimensional structures.
RESUMEN
Field-effect transistors (FETs) have tremendous applications in the electronics industry due to their outstanding features such as small size, easy fabrication, compatibility with integrated electronics, high sensitivity, rapid detection and easy measuring procedures. However, to meet the increasing demand of the electronics industry, efficient FETs with controlled short channel effects, enhanced surface stability, reduced size, and superior performances based on low-dimensional materials are desirable. In this review, we present the developmental roadmap of FETs from conventional to miniaturized devices and highlight their prospective applications in the field of optoelectronic devices. Initially, a detailed study of the general importance of bulk and low-dimensional materials is presented. Then, recent advances in low-dimensional material heterostructures, classification of FETs, and the applications of low-dimensional materials in field-effect transistors and photodetectors are presented in detail. In addition, we also describe current issues in low-dimensional material-based FETs and propose potential approaches to address these issues, which are crucial for developing electronic and optoelectronic devices. This review will provide guidelines for low-dimensional material-based FETs with high performance and advanced applications in the future.
RESUMEN
In recent years, self-healing property has getting tremendous attention in the future wearable electronic. This paper proposes a novel cut-able and highly stretchable strain sensor utilizing a self-healing function from magnetic force of magnetic iron oxide and graphene nano-composite on an engineered self-healable polyurethane substrate through commercialized inkjet printer DMP-3000. Inducing the magnetic property, magnetic iron oxide is applied to connect between graphene flacks in the nano-composite. To find the best nano-composite, the optimum graphene and magnetic iron oxide blending ratio is 1:1. The proposed sensor shows a high mechanical fracture recovery, sensitivity towards strain, and excellent self-healing property. The proposed devices maintain their performance over 10,000 times bending/relaxing cycles, and 94% of their function are recovered even after cutting them. The device also demonstrates stretchability up to 54.5% and a stretching factor is decreased down to 32.5% after cutting them. The gauge factor of the device is 271.4 at 35%, which means its sensitivity is good. Hence, these results may open a new opportunity towards the design and fabrication of future self-healing wearable strain sensors and their applied electronic devices.
RESUMEN
Introducing hole/electron transporting and blocking layers is considered to enhance the performance of electronic devices based on organic-inorganic hybrid halide perovskite single crystals (PSCs). In many photodiodes, the hole/electron transporting or blocking materials are spin-coated or thermal-evaporated on PSC to fabricate heterojunctions. However, the heterojunction interfaces due to lattice mismatch between hole/electron, transporting or blocking materials and perovskites easily form traps and cracks, which cause noise and leakage current. Besides, these low-mobility transporting layers increase the difficulty of transporting carriers generated by photons to the electrode; hence, they also increase the response time for photo detection. In the present study, MAPbCl3-MAPbBr2.5Cl0.5 heterojunction interfaces were realized by liquid-phase epitaxy, in which MAPbBr2.5Cl0.5 PSC acts as an active layer and MAPbCl3 PSC acts as a hole blocking layer (HBL). Our PIN photodiodes with epitaxial MAPbCl3 PSC as HBL show better performance in dark current, light responsivity, stability, and response time than the photodiodes with spin-coated organic PCBM as HBL. These results suggest that the heterojunction interface formed between two bulk PSCs with different halide compositions by epitaxy growth is very useful for effectively blocking the injected charges under high external electric field, which could improve the collection of photo-generated carriers and hereby enhance the detection performance of the photodiode. Furthermore, the PIN photodiodes made of PSC with epitaxial HBL show the sensitivities of 7.08 mC Gyair -1 cm-2, 4.04 mC Gyair -1 cm-2, and 2.38 mC Gyair -1 cm-2 for 40-keV, 60-keV, and 80-keV X-ray, respectively.