FlexMat最新文献

It is significant to develop stretchable electronics based on silicon materials for practical applications. Although various stretchable silicon structures have been reported, electronic systems based on them exhibit limited stretchability due to the constraints between them and polymer substrates. Here, an innovative strategy of deformation mismatch is proposed to break the constraints between silicon structures and polymers and effectively reduce the strain concentration in silicon structures. As a result, encapsulated serpentine silicon strips (S-Si strips) achieve unprecedented stretchability, exceeding 120%. The encapsulated S-Si strip also exhibits remarkable mechanical stability and durability, enduring 100 000 cycles of 100% stretch without fracture. The effect of key parameters, including the central angle, thickness, and width of the S-Si strip, on the deformation mismatch is revealed through combing experiments and theoretical analysis, which will guide the rational implementation of the deformation mismatch strategy. Electrical testing showcases the strain-insensitive nature and good electrical stability of encapsulated S-Si strips, benefiting practical applications. This work provides a new paradigm of silicon materials with excellent stretchability and will facilitate the development of stretchable electronics.

In recent decades, the microelectronics industry has developed rapidly based on the von Neumann architecture and under the guidance of Moore's law. However, as the size of electronic devices approaches the limit and power consumption increases, traditional microelectronic materials and devices are facing more and more challenges. As a new type of semiconductor material, halide perovskites (HPs) have excellent photoelectric characteristics, such as high carrier mobility, controllable band structure, etc., which have been widely used in solar cells, light emitting diodes (LEDs), photodetectors, memristors, and in other fields. Among them, the memristor, as a new type of electronic device, is very promising for in-memory computing with low power consumption by breaking the limit of von Neumann architecture. Especially, HPs-based memristors show outstanding photoelectric response performance, low power consumption, and flexible wearability, allowing them to hold great application potential in logical operation, polymorphic storage, and neuromorphic computing, etc. In this review, we first briefly introduce the basic characteristics and preparation methods of HPs. Secondly, the development history, device structure, and performance parameters of memristors are depicted in detail. Thirdly, the resistance mechanism and application of HPs-based memristors are discussed. Finally, the research status and development prospects of HPs-based memristors are outlined.

Covalent organic frameworks (COFs) are porous materials with good crystallinity, highly ordered stacking, tunable channels, and diverse functional groups that have been demonstrated to show great potential applications in flexible electronic devices, including flexible energy storage devices (batteries and supercapacitors), memristors and sensors. Although great research progress on the usage of COFs as active elements in flexible electronics has been witnessed, the summary in this direction is rare. Thus, it is the right time to write a review on COFs-based flexible electronics. In this review, we will first discuss the different synthesis strategies to prepare COF materials. Then, the applications of COFs in flexible electronic devices are summarized. Finally, the future performance improvement and development directions of COFs in the field of flexible electronic devices are briefly outlined. This review could provide basic concepts and some guidelines to stimulate novel applications of COFs in diverse flexible electronic devices.

Purely organic room temperature phosphorescence (RTP) materials have shown broad application prospects in organic light-emitting diodes (OLEDs) due to their theoretical 100% exciton utilization, cost-effectiveness, and flexibility. In recent years, with the deepening of research, various luminescent mechanisms have been proposed, and RTP materials have made significant progress, which have been effectively applied to OLEDs. This article comprehensively reviews the research progress of RTP materials in OLEDs and introduces the development of a series of high-efficiency RTP materials from the perspective of molecular design strategies and photophysical properties. These conclusions draw a roadmap to address the inherent challenges in utilizing organic RTP materials to specifically advance the investigation of OLEDs.

The construction of multi-decay pathways of smart organic light-emitting materials has drawn intensive research enthusiasm owing to their substantial promise in diverse optoelectronic applications. Nowadays, numerous chemical substances have been refined to extend and enhance their intriguing luminescent properties. Nowadays, plenty of chemicals have been adapted to amplify more interesting luminescent properties. How to utilize an easy way to tune multi-decay pathways resulting in various emissions is still challenging. Here, we present a triphenylamine derivative, TPA3BP, which exhibits a variety of multi-decay pathways in different states and can exhibit thermally activated delayed fluorescence in both the polydimethylsiloxane and crystalline state, but also achieve room temperature phosphorescence by embedding it into the poly (methyl methacrylate) (PMMA) and polyvinyl pyrrolidone matrix. The multi-decay luminescence can be attributed to the dual effect arising from the n-π* transition of TPA3BP and the regulation of molecular transition pathways within the matrix environment. This intriguing phenomenon highlights the combined influence of TPA3BP's electronic transitions and the influence of the polarity and rigidity of the surrounding matrix on the observed characteristics. This advancement has widened the structural possibilities for multi-decay luminescent materials, enabling their targeted synthesis for future applications, such as information encryption and smart anti-counterfeiting.

Given the widespread presence of intricate surfaces, the development of electronics has generated a significant demand for surface patterning techniques capable of creating refined or novel patterns. Nevertheless, present surface patterning techniques suffer from complex processes, limited resolution, stringent conditions, and high manufacturing costs. Herein, we present a novel approach for arbitrary surface micropatterning using photosensitive polyimide (PSPI), enabling the in situ fabrication of electrodes without the need for a pattern-transferring process. On this basis, we have implemented a high-performance, freestanding flexible thin-film mask with high optical transparency that facilitates precise alignment of microelectrode patterns with the target material. It also exhibits exceptional mechanical properties suitable for long-term use and high-temperature applications, with a notable glass transition temperature of up to 300°C. The fabricated masks with thicknesses of 5–20 μm are well-suited for high-resolution applications, including those requiring sub-5 μm resolution. Furthermore, the creation of microelectrodes on a variety of surfaces utilizing the fabricated PSPI masks was successfully demonstrated. Our facile method provides a solid foundation for achieving efficient micropatterning for the fabrication of high-performance flexible electronics on complex surfaces.

Organic solar cells (OSCs) have attracted significant attention as a burgeoning flexible technology, owing to their advanced power conversion efficiencies. Moreover, interface materials play a crucial role in optimizing energy level alignment between the active layer and electrodes, thereby enhancing carrier extraction within the device and improving efficiency. However, current methodologies for fabricating electron-transport materials with superior mobility are still limited compared with those for hole-transport materials. In this study, a benzodifurandione (BFDO)-derived building block with quinone resonance property and strong electron-withdrawing capability was synthesized. Two conjugated polymers, namely PBFDO-F6N and PBFDO-F6N-Br, were prepared, both of which exhibited good electron mobility and exceptional interface modification capabilities. A comprehensive investigation of the interaction between the interface layer and the active layer revealed that PBFDO-F6N induced doping at the acceptor interface. Additionally, the high mobility of PBFDO-F6N facilitated efficient carrier extraction at the interface. Consequently, the application of PBFDO-F6N as the cathode interface layer for PM6:BTP-eC9-based OSC devices resulted in a remarkable efficiency of 18.11%. Moreover, the device efficiency remained at ∼96% even at a PBFDO-F6N interface thickness of 50 nm, demonstrating the great potential of this material for large-scale device preparation.

Counterfeiting remains a significant threat, causing economic and safety concerns. Addressing this, authentication technologies have gained traction. With the rise of the Internet of Things, authentication is crucial. Photonic Physical Unclonable Functions (PUFs) offer unique identifiers. We present low-cost and sustainable e-tags that may be printed virtually on any surface for authentication due to the bespoke texturization of sustainable inks of surface-modified carbon dots. A single e-tag provides randomized phosphorescence (or afterglow) patterns, which provide multiple layers of safety by exploiting different patterning, excitation energies, and temporal characteristics. A comprehensive case study employing photonic challenge-response pairs, involving a sample size of up to 2⁹ emission spectra in combination with 10² photographs taken with a smartphone, displays a low authentication probability of error (<10⁻¹¹), which supports the potential of our combined approach toward the development of more robust photonic PUF systems.

Biomarker identification is a tried-and-true method that can provide precise biological information for disease diagnosis. Prompt diagnosis, disease progression monitoring, therapy efficacy evaluation, and prognosis assessment of cancers all benefit from sensitive, rapid, and precise measurement of significant biomarkers employing chemical and immunological approaches. The study of biomolecules and immunoassay evaluations can profit greatly from recent advancements in flexible electronic materials and technologies, which provide amazing flexibility, affordability, mobility, and integration. However, an overview of the implementation of portable immunoassays in conjunction with flexible electronic devices is rare to come by. This review focuses on recent breakthroughs in flexible electronic materials and devices for portable biomarker testing, which provides an extensive summary of flexible electrical components and sensing-capable devices, emphasizing their adaptability in the construction of biosensing platforms. These platforms employ various signal transduction systems to record biological affinity recognition events, including pressure, temperature, electrical parameters, colorimetric signals, and other physical features. The challenges for portable, integrated, intelligent, and multifunctional immunoassays based on flexible sensing devices are also discussed. The portable immunoassays with flexible electronics would unlock the potential to transform clinical diagnostics into non-clinical personalized treatments and achieve home-based point-of-care testing for daily monitoring.