Flexible and Stretchable Organic Electrochemical Transistors for Physiological Sensing Devices

Abstract

Flexible and stretchable bioelectronics provides a biocompatible interface between electronics and biological systems and has received tremendous attention for in situ monitoring of various biological systems. Considerable progress in organic electronics has made organic semiconductors, as well as other organic electronic materials, ideal candidates for developing wearable, implantable, and biocompatible electronic circuits due to their potential mechanical compliance and biocompatibility. Organic electrochemical transistors (OECTs), as an emerging class of organic electronic building blocks, exhibit significant advantages in biological sensing due to the ionic nature at the basis of the switching behavior, low driving voltage (<1 V), and high transconductance (in millisiemens range). During the past few years, significant progress in constructing flexible/stretchable OECTs (FSOECTs) for both biochemical and bioelectrical sensors has been reported. In this regard, to summarize major research accomplishments in this emerging field, this review first discusses structure and critical features of FSOECTs, including working principles, materials, and architectural engineering. Next, a wide spectrum of relevant physiological sensing applications, where FSOECTs are the key components, are summarized. Last, major challenges and opportunities for further advancing FSOECT physiological sensors are discussed.

Smart Textile Optoelectronics for Human‐Interfaced Logic Systems

“…Fibrous OECT has also been developed to directly diagnose metabolites (e.g., sweat, dopamine, potassium ions, glucose, and lactate). [ 233–239 ] Wang et al. designed a fiber OECT by polymerizing PPy nanowire on rGO‐coated PA fiber, which achieved a sensitivity of 0.773 NCR per decade over a wide range of 1 n m to 5 µ m .…”

“…[232] Fibrous OECT has also been developed to directly diagnose metabolites (e.g., sweat, dopamine, potassium ions, glucose, and lactate). [233][234][235][236][237][238][239] Wang et al designed a fiber OECT by polymerizing PPy nanowire on rGO-coated PA fiber, which achieved a sensitivity of 0.773 NCR per decade over a wide range of 1 nm to 5 μm. [240] Wu et al demonstrated a CNT-fiber-based OECT using PEDOT:PSS as an active layer, achieving biochemical detection of H 2 O 2 , glucose, dopamine, and glutamate.…”

Matrix‐Driving Stretchable Structural Colors in Multi‐Pixels Operation Using Chiral Liquid Crystal Elastomers

“…Because of such a strain distribution, only a limited uniform structural color control can be realized during the stretching tuning process, even if multi-pixel-arrayed photonic structures are used. [26,45] Also, it should be noted that this strain distribution is problematic not only in mechanochromic structural colors, but also in most multi-pixel requiring stretchable technologies [46,47] as well. Shortly, switching uniformity in multi-pixel operations is a major technical challenge in most stretchable technologies for practical uses.…”

Cyano-functionalized organic and polymeric semiconductors for high-performance n-type organic electronic devices

“…Organic and polymeric semiconductors have gained widespread attention owing to their unique advantages of being lightweight, excellent mechanical trait and solution processability, which has led to various applications in organic electronic devices, such as organic solar cells (OSCs), organic thin-film transistors (OTFTs), organic thermoelectrics (OTEs), and organic electrochemical transistors (OECTs). [1][2][3][4][5] Organic and polymeric semiconductors can be divided into p-type and n-type ones based on the charge carrier polarity. Over the past few decades, p-type organic semiconductors have achieved great success in terms of material diversity and device performance.…”