查看更多>>摘要：Optical communication is a particularly compelling technology for tackling the speed and capacity bottlenecks in data communication in modern society.Currently,the silicon photodetector plays a dominant role in high-speed optical communication across the visible-near-infrared spectrum.However,its intrinsic rigid structure,high working bias and low responsivity essentially limit its application in next-generation flexible optoelectronic devices.Herein,we report a narrow-bandgap non-fullerene acceptor(NFA)with a remarkable π-extension in the direction of both central and end units(CH17)with respect to the Y6 series,which demonstrates a more effective and compact 3D molecular packing,leading to lower trap states and energetic disorders in the photoactive film.Consequently,the optimized solution-processed organic photodetector(OPD)with CH 17 exhibits a remarkable response time of 91 ns(λ=880 nm)due to the high charge mobility and low parasitic capacitance,exceeding the values of most commercial Si photodiodes and all NFA-based OPDs operating in self-powered mode.More significantly,the flexible OPD exhibits negligible performance attenuation(＜1％)after bending for 500 cycles,and maintains 96％of its initial performance even after 550 h of indoor exposure.Furthermore,the high-speed OPD demonstrates a high data transmission rate of 80 MHz with a bit error rate of 3.5 x 10-4,meaning it has great potential in next-generation high-speed flexible optical communication systems.
查看更多>>摘要：Tunability of optical performance is one of the key technologies for adaptive optoelectronic applications,such as camouflage clothing,displays,and infrared shielding.High-precision spectral tunability is of great importance for some special applications with on-demand adaptability but remains challenging.Here we demonstrate a galvanostatic control strategy to achieve this goal,relying on the finding of the quantitative correlation between optical properties and electrochemical reactions within materials.An electrochromic electro-optical efficiency index is established to optically fingerprint and precisely identify electrochemical redox reactions in the electrochromic device.Consequently,the charge-transfer process during galvanostatic electrochemical reaction can be quantitatively regulated,permitting precise control over the final optical performance and on-demand adaptability of electrochromic devices as evidenced by an ultralow deviation of＜3.0％.These findings not only provide opportunities for future adaptive optoelectronic applications with strict demand on precise spectral tunability but also will promote in situ quantitative research in a wide range of spectroelectrochemistry,electrochemical energy storage,electrocatalysis,and material chemistry.
查看更多>>摘要：The rise in wearable electronics has witnessed the advancement of self-healable wires,which are capable of recovering mechanical and electrical properties upon structural damage.However,their highly fluctuating electrical resistances in the range of hundreds to thousands of ohms under dynamic conditions such as bending,pressing,stretching and tremoring may seriously degrade the precision and continuity of the resulting electronic devices,thus severely hindering their wearable applications.Here,we report a new family of self-healable wires with high strengths and stable electrical conductivities under dynamic conditions,inspired by mechanical-electrical coupling of the myelinated axon in nature.Our self-healable wire based on mechanical-electrical coupling between the structural and conductive components has significantly improved the electrical stability under dynamic scenarios,enabling precise monitoring of human health status and daily activities,even in the case of limb tremors from simulated Parkinson's disease.Our mechanical-electrical coupling strategy opens a new avenue for the development of dynamically stable electrodes and devices toward real-world wearable applications.
查看更多>>摘要：Enhancing the thermoelectric transport properties of conductive polymer materials has been a long-term challenge,in spite of the success seen with molecular doping strategies.However,the strong coupling between the thermopower and the electrical conductivity limits thermoelectric performance.Here,we use polaron interfacial occupied entropy engineering to break through this intercoupling for a PEDOT:PSS(poly(3,4-ethylenedioxythiophene)-poly(4-styrenesulfonate))thin film by using photochromic diarylethene(DAE)dopants coupled with UV-light modulation.With a 10-fold enhancement of the thermopower from 13.5 μV K-1to 135.4 μV K-1 and almost unchanged electrical conductivity,the DAE-doped PEDOT:PSS thin film achieved an extremely high power factor of521.28 µW m-1 K-2 from an original value of 6.78 μW m-1 K-2.The thermopower was positively correlated with the UV-light intensity but decreased with increasing temperature,indicating resonant coupling between the planar closed DAE molecule and PEDOT.Both the experiments and theoretical calculations consistently confirmed the formation of an interface state due to this resonant coupling.Interfacial entropy engineering of polarons could play a critical role in enhancing the thermoelectric performance of the organic film.
查看更多>>摘要：Flexible devices and functional systems with elaborated three-dimensional(3D)architectures can endow better mechanical/electrical performances,more design freedom,and unique functionalities,when compared to their two-dimensional(2D)counterparts.Such 3D flexible devices/systems are rapidly evolving in three primary directions,including the miniaturization,the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous integration.Intractable challenges exist in this emerging research area,such as relatively poor controllability in the locomotion of soft robotic systems,mismatch of bioelectronic interfaces,and signal coupling in multi-parameter sensing.By virtue of long-time-optimized materials,structures and processes,natural organisms provide rich sources of inspiration to address these challenges,enabling the design and manufacture of many bioinspired 3D flexible devices/systems.In this Review,we focus on bioinspired 3D flexible devices and functional systems,and summarize their representative design concepts,manufacturing methods,principles of structure-function relationship and broad-ranging applications.Discussions on existing challenges,potential solutions and future opportunities are also provided to usher in further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes,enhanced mechanical/electrical performances,and high-level physical/artificial intelligence.
NETL
NSTL
万方数据