Miaoxiang Chen

Bio: Miaoxiang Chen is an academic researcher from Linköping University. The author has contributed to research in topics: PEDOT:PSS & Conductive polymer. The author has an hindex of 9, co-authored 13 publications receiving 992 citations.

Active Matrix Displays Based on All‐Organic Electrochemical Smart Pixels Printed on Paper

Abstract: An organic electronic paper display technology (see Figure and also inside front cover) is presented. The electrochromic display cell together with the addressing electrochemical transistor form si ...

Bi-stable and dynamic current modulation in electrochemical organic transistors

Abstract: Novel electrochemical transistors, based on the conductive polymer PEDOT, operating at driving voltages of only a few volts in bulk material, and with little demand on substrate planarity, are desc ...

1 micron wavelength photo- and electroluminescence from a conjugated polymer

Abstract: We report photo- and electroluminescence from an alternating conjugated polymer consisting of fluorene units and low-band gap donor-acceptor-donor (D–A–D) units. The D–A–D segment includes two elec ...

Electric current rectification by an all-organic electrochemical device

Abstract: An all-organic printed electrochemical rectifier is reported. The device is based on a patterned layer of poly(3,4-ethylenedioxythiophene) poly(styrene sulfonate) (PEDOT:PSS) that interfaces a patterned electrolyte top layer. Overlap between the electrolyte layer and the conducting polymer pattern results in the formation of two electrochemically active areas within the conducting polymer pattern. When bias voltage is applied across the conducting polymer pattern, the PEDOT in the negatively biased areas is reduced electrochemically, while the PEDOT in the positively biased area is further oxidized. Reducing PEDOT from its p-doped, pristine state to the neutral state results in a marked loss of electrical conductivity. Due to the unsymmetrical device geometry, the current through the device may be shut off for one polarity of applied bias voltage with an electrical current rectification ratio of 100 compared to the opposite polarity. The output characteristics of a corresponding half wave rectifier as well as those from a full wave bridge rectifier show stable performance at frequencies below 15 Hz.

High carrier mobility in low band gap polymer-based field-effect transistors

Abstract: A conjugated polymer with a low band gap of 1.21 eV, i.e., absorbing infrared light, is demonstrated as active material in field-effect transistors (FETs). The material consists of alternating fluo ...

Semiconducting π-conjugated systems in field-effect transistors: a material odyssey of organic electronics.

Abstract: Since the discovery of highly conducting polyacetylene by Shirakawa, MacDiarmid, and Heeger in 1977, π-conjugated systems have attracted much attention as futuristic materials for the development and production of the next generation of electronics, that is, organic electronics. Conceptually, organic electronics are quite different from conventional inorganic solid state electronics because the structural versatility of organic semiconductors allows for the incorporation of functionality by molecular design. This versatility leads to a new era in the design of electronic devices. To date, the great number of π-conjugated semiconducting materials that have either been discovered or synthesized generate an exciting library of π-conjugated systems for use in organic electronics. 11 However, some key challenges for further advancement remain: the low mobility and stability of organic semiconductors, the lack of knowledge regarding structure property relationships for understanding the fundamental chemical aspects behind the structural design, and realization of desired properties. Organic field-effect transistors (OFETs) are a kind of device consisting of an organic semiconducting layer, a gate insulator layer, and three terminals (drain, source, and gate electrodes). OFETs are not only essential building blocks for the next generation of cheap and flexible organic circuits, but they also provide an important insight into the charge transport of πconjugated systems. Therefore, they act as strong tools for the exploration of the structure property relationships of πconjugated systems, such as parameters of field-effect mobility (μ, the drift velocity of carriers under unit electric field), current on/off ratio (the ratio of the maximum on-state current to the minimum off-state current), and threshold voltage (the minimum gate voltage that is required to turn on the transistor). 17 Since the discovery of OFETs in the 1980s, they have attracted much attention. Research onOFETs includes the discovery, design, and synthesis of π-conjugated systems for OFETs, device optimization, development of applications in radio frequency identification (RFID) tags, flexible displays, electronic papers, sensors, and so forth. It is beyond the scope of this review to cover all aspects of π-conjugated systems; hence, our focus will be on the performance analysis of π-conjugated systems in OFETs. This should make it possible to extract information regarding the fundamental merit of semiconducting π-conjugated materials and capture what is needed for newmaterials and what is the synthesis orientation of newπ-conjugated systems. In fact, for a new science with many practical applications, the field of organic electronics is progressing extremely rapidly. For example, using “organic field effect transistor” or “organic field effect transistors” as the query keywords to search the Web of Science citation database, it is possible to show the distribution of papers over recent years as shown in Figure 1A. It is very clear

Synthesis of Light-Emitting Conjugated Polymers for Applications in Electroluminescent Devices

Abstract: A review was presented to demonstrate a historical description of the synthesis of light-emitting conjugated polymers for applications in electroluminescent devices. Electroluminescence (EL) was first reported in poly(para-phenylene vinylene) (PPV) in 1990 and researchers continued to make significant efforts to develop conjugated materials as the active units in light-emitting devices (LED) to be used in display applications. Conjugated oligomers were used as luminescent materials and as models for conjugated polymers in the review. Oligomers were used to demonstrate a structure and property relationship to determine a key polymer property or to demonstrate a technique that was to be applied to polymers. The review focused on demonstrating the way polymer structures were made and the way their properties were controlled by intelligent and rational and synthetic design.

Stretchable form of single crystal silicon for high performance electronics on rubber substrates

Abstract: The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.

Stretchable active-matrix organic light-emitting diode display using printable elastic conductors

Abstract: Stretchability will significantly expand the applications scope of electronics, particularly for large-area electronic displays, sensors and actuators. Unlike for conventional devices, stretchable electronics can cover arbitrary surfaces and movable parts. However, a large hurdle is the manufacture of large-area highly stretchable electrical wirings with high conductivity. Here, we describe the manufacture of printable elastic conductors comprising single-walled carbon nanotubes (SWNTs) uniformly dispersed in a fluorinated rubber. Using an ionic liquid and jet-milling, we produce long and fine SWNT bundles that can form well-developed conducting networks in the rubber. Conductivity of more than 100 S cm(-1) and stretchability of more than 100% are obtained. Making full use of this extraordinary conductivity, we constructed a rubber-like stretchable active-matrix display comprising integrated printed elastic conductors, organic transistors and organic light-emitting diodes. The display could be stretched by 30-50% and spread over a hemisphere without any mechanical or electrical damage.