Pei HeCentral South University | CSU · School of Physics and Electronics
Pei He
Doctor of Philosophy
About
40
Publications
11,937
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
1,458
Citations
Citations since 2017
Introduction
• Functional inks based on two-dimensional materials (graphene, graphene oxide, reduced graphene oxide, black phosphorus, metal dichalcogenides, et al)
• Printing of 2D materials for electronics applications
• Fabrication of structural and functional components by printing process
• Control of fluid/substrate interactions during ink printing process
Publications
Publications (40)
Continuous conducting lines of width 5-20 μm have been printed with a Ag nanoparticle ink using drop-on-demand (DOD) electrohydrodynamic (EHD) inkjet printing on Si and PDMS substrates, with advancing contact angles of 11° and 35°, respectively, and a zero receding contact angle. It is only possible to achieve stable parallel sided lines within a l...
With the development of neuromorphic electronics, much effort has been devoted to the design and manufacture of synaptic electronic devices with large scale and cost-efficient. In this paper, an In 2 O 3 synaptic transistor array gated by screen-printed ion-gel was demonstrated. Due to the ion-gel/Al 2 O 3 stacked gate dielectric, all devices on th...
Wearable strain sensors are appealing for monitoring human activities and evaluating human health. However, the development of wearable strain sensors with high sensitivity, large-scale manufacturing ability as well as the using of eco-friendly raw materials is still challenging. In this work, a simple and environmentally friendly high-performance...
Wearable healthcare sensors can perform real-time health monitoring by tracking various physical signals, physiological signals, as well as electrophysiological activities of the human body. Liquid metals have become an ideal candidate material for wearable healthcare sensors due to their excellent physical and chemical properties, such as high str...
Conductive inks have attracted tremendous attention owing to their adaptability and the convenient large-scale fabrication. As a new type of conductive ink, copper-based ink is considered to be one of the best candidate materials for the conductive layer in flexible printed electronics owing to its high conductivity and low price, and suitability f...
Metal halide perovskites (MHPs) show excellent optoelectronic properties and exhibit great potential applications in optoelectronic devices, such as solar cells (SCs), photodetectors, light-emitting diodes (LEDs), lasers, and so on. Vapor-phase synthesis provides an important way to grow large-scale, high-quality MHP thin films and micro-/nanostruc...
Strain sensors with good stability are vital to the development of wearable healthcare monitoring systems. However, the design of strain sensor with both duration stability and environmental stability is still a challenge. In this work, we propose an ultra-stable and washable strain sensor by embedding a coupled composite film of carbon nanotube (C...
Organic-inorganic hybrid perovskite solar cells (PSCs) are continuously attracting much attention due to the poential applications in low-cost and flexible solar energy system. In this work, potassium (K⁺) and cesium (Cs⁺) were added into the perovskite (FAMA)Pb(IBr)3 (FA = CH(NH2)2⁺, MA = CH3NH3⁺) to prepare the high-quality quadruple-cation (KCsM...
Organic thin film transistors (OTFTs) are normally sensitive to ambient conditions and show performance degradation in air. On the contrary, the performance of flexible 2,7-dioctyl[1] benzothieno [3,2-b][1]benzothiophene (C8-BTBT) OTFTs using cross-linked polymer layer, poly(4-vinyl-phenol)-4,4′-(hexafluoroisopropylidene) diphthalic anhydride (PVP-...
Carbon is widely used as the electrode material in supercapacitors but has not reached its maximum performance due to poor optimization of electrode-electrolyte interaction. Taking inspiration from recent advances in “water in salt” electrolytes where the electrochemistry changes significantly due to the scarcity of free water, we propose a new ele...
Conductive graphene inks have attracted extensive research interests for printed electronics due to the excellent electrical and mechanical properties of graphene. While the traditional organic solvents used for graphene inks will result in high environmental cost, environmentally friendly solvents are required for conductive graphene inks. In this...
Owing to the unique characteristics such as electron mobility, large surface area, mechanical robustness, and so on, two-dimensional (2D) materials have vast potential for the applications in electronic devices. However, many of the demonstrated devices are based on mechanically exfoliated 2D materials that limit their wider applications. In fact,...
Flexible strain sensors exhibit outstanding advantages in terms of sensitivity and stability by detecting changes in physical signals. It can be easily attached to human skin and clothed to achieve monitoring of human motion and health. However, general sensing materials shows low stretchability and cannot respond to signals under large deformation...
The electrodeposition of conducting polymer-carbon composites from an electrolyte precursor solution is a facile one-step approach to fabricate device-ready electrodes for energy storage. A key challenge in this approach is the dispersion of the carbon nanomaterials with the aqueous precursor solution, with previous approaches either heavily oxidis...
Perovskite cesium lead halide (CsPbBr3) has attracted a considerable attention due to its excellent optoelectronic properties and superior stability against moisture, oxygen, light, and heat. In this work, the micro-environment controlled chemical vapor deposition (CVD) method has been adopted to synthesize high-quality single-crystalline CsPbBr3 m...
This work demonstrated a dry electrode for electrocardiogram (ECG) monitoring based on graphene-coated cotton fabric by screen printing process. The cotton fabric was fully covered by the graphene flakes, which makes the sheet resistance of cotton fabric reaches as low as 42.2 Ω/sq. The ECG signals obtained from the graphene-coated textile electrod...
Conductive inks for the future printed electronics should have the following merits: high conductivity, flexibility, low cost and compatibility with wide range of substrates. However, the state-of-the-art conductive inks based on metal nanoparticles are high in cost and poor in flexibility. Herein, we reported a highly conductive, low cost and supe...
Electrocardiogram (ECG) signals are crucial for determining the health status of the human heart. A clean ECG signal is critical in analysis and diagnosis of heart diseases. However, ECG signals are often contaminated by motion artifact noise in the non-contact ECG monitoring systems. In this paper, an ECG motion artifact removal approach based on...
Multifunctional wearable e-textiles have been a focus of much attention due to their great potential for healthcare, sportswear, fitness, space, and military applications. Among them, electroconductive textile yarn shows great promise for use as next-generation flexible sensors without compromising the properties and comfort of usual textiles. Howe...
2D materials show considerable promise as high surface area electrodes for energy storage applications such as supercapacitors. A single sheet of graphene possesses a large specific surface area due to its atomically thin thickness. However, in order to package this area efficiently in a device, it must be confined within a finite 3D volume without...
Fully printed humidity sensors based on two dimensional (2D) materials are described. Monolayer graphene oxide (GO) and few-layered black phosphorus (BP) flakes were dispersed in low boiling point solvents suitable for inkjet printing. The humidity sensors were fabricated by printing of GO and BP sensing layers on printed silver nanoparticle electr...
Graphene-based wearable e-textiles are considered to be promising due to their advantages over traditional metal-based technology. However the manufacturing process is complex and currently not suitable for industrial scale application. Here we report a simple, scalable and cost-effective method of producing graphene-based wearable e-textiles throu...
Conventional chemical oxidation routes for the production of graphene oxide (GO), such as the Hummers method, suffer from environmental and safety issues due to their use of hazardous and explosive chemicals. These issues are addressed by electrochemical oxidation methods but such approaches typically have a low yield due to inhomogeneous oxidation...
The morphology of drops of graphene oxide (GO) inks produced by inkjet printing shows a distinctive coffee ring after drying when the mean diameter of the GO is below a critical size. Inks with larger diameter flakes do not show a coffee ring and the transition mean flake diameter decreases as the substrate temperature increases and when the printe...
Graphene oxide 2D materials inks with mean flake diameter 36 µm can be inkjet printed, with no significant blockage of the printer or apparent damage to the flakes, despite the mean flake size being >50% of the printer nozzle diameter and the ink containing individual flakes considerably larger than the nozzle. Printed flakes show a similar level o...
Graphene is a strong contender as a material to replace indium tin oxide as the transparent conductor of choice for electronic applications due to its exceptional electrical and optical properties. In this work, we present a study of graphene oxide (GO) films produced by inkjet-printing. The printed GO films are reduced using hydriodic acid (HI) an...
ITO-free organic photovoltaic (OPV) devices with all solution processed transparent anodes of PEDOT:PSS/inkjet printed Ag grid were demonstrated. Through process control, the polymer/metal grid hybrid electrode films are of transparency close to 80% and sheet resistance of 48 ohms/sq. A power efficiency of 1.73% was achieved for the OPV device. The...
This paper reviews the latest technology advances of ultra-low power displays and plastic solar cells, and discuss the possibility to integrate the two technologies into the mobile electronics system for efficient power harvesting and utilization.
A general and comprehensive hybrid simulation platform(HSP) is developed for conveniently evaluating and optimizing the backlight design and driving schemes in TFT-LCDs to achieve low power and excellent image quality. It incorporates a range of capabilities from the early backlight optical simulation to the performance evaluation and optimization...
Projects
Projects (3)
In this project we propose to develop a low-cost technique to be able to print such heterostructures from 2D inks. Several members of the consortium have already demonstrated that tunnelling diodes, tunnelling transistors and photodetectors can be printed using standard mass-production technologies. We will significantly increase the range of heterostructures produced by such methods, and will specifically concentrate on heterostructures which produce active response (thermo-power, piezoelectric, photovoltaic, etc). Such heterostructures can act as sensors in a number of applications. We will then combine this technology with already developed technique of printing RFID antenna by using graphene inks. This would allow us to create RFID sensors of different types which do not require power source. For instance, we can record temperature of a product or illumination this product has been subjected to. Multifunctional sensors can naturally be achieved with such technique (for instance temperature, strain and humidity could be recorded at the same time).
To develop a range of graphene-based inks suitable for wearable e-textiles applications;
2. To develop scalable and cost-effective fabrication techniques for graphene-based wearable e-textiles;
3. To fabricate a range of graphene-based wearable e-textile devices using optimised graphene inks and fabrication techniques (coating and printing);
4. To investigate the effect of pre and post-treatment on the performance of conductive textiles; and
5. To investigate the performance properties (such as tensile strength, washability, flexibility and hand properties) of graphene-based e-textiles.
