Multifunctional high-performance pressure/proximity/temperature sensors enabled by hybrid resistive-supercapacitive response

The issue of sensitivity attenuation in high-pressure region has been a persistent concern for pressure-sensitive electronic skins.In order to tackle such trade-off between sensitivity and linear range,herein,a hybrid piezoresistive-supercapacitive(HRSC)strategy is proposed via introducing a piezoresistive porous aerogel layer between the charge collecting electrodes and iontronic films of the pressure sensors.Surprisingly,the HRSC-induced impedance regulation and supercapacitive behavior contribute to significant mitigation in sensitivity attenuation,achieving high sensitivity across wide linear range(44.58 kPa^(−1)from 0 to 3 kPa and 23.6 kPa^(−1)from 3 to 12 kPa).The HRSC pressure sensor exhibits a low detection limit of 1 Pa,fast responsiveness(~130 ms),and excellent cycling stability,allowing to detect tiny pressure of air flow,finger bending,and human respiration.Meanwhile,the HRSC sensor exhibits exceptional perception capabilities for proximity and temperature,broadening its application scenarios in prosthetic perception and electronic skin.The proposed HRSC strategy may boost the ongoing research on structural design of high-performance and multimodal electronic sensors.

Recent advances in multimodal sensing integration and decoupling strategies for tactile perception

Human skin perceives external environmental stimulus by the synergies between the subcutaneous tactile corpuscles.Soft electronics with multiple sensing capabilities by mimicking the function of human skin are of significance in health monitoring and artificial sensation.The last decade has witnessed unprecedented development and convergence between multimodal tactile sensing devices and soft bioelectronics.Despite these advances,traditional flexible electronics achieve multimodal tactile sensing for pressure,strain,temperature,and humidity by integrating monomodal sensing devices together.This strategy results in high energy consumption,limited integration,and complex manufacturing process.Various multimodal sensors and crosstalk-free sensing mechanisms have been proposed to bridge the gap between natural sensory system and artificial perceptual system.In this review,we provide a comprehensive summary of tactile sensing mechanism,integration design principles,signal-decoupling strategies,and current applications for multimodal tactile perception.Finally,we highlight the current challenges and present the future perspectives to promote the development of multimodal tactile perception.

全固态离子选择性电极在可穿戴电化学传感器中的进展

人体汗液富含丰富的与身体健康状况相关的电解质,采用可穿戴电化学离子传感器对汗液实时监测可为身体健康提供合理的指导.基于全固态离子选择性电极的可穿戴电化学传感器因能够实时无创地分析生物体液离子受到越来越多的关注.开发新的固接层材料,探索新的电位响应机理及在可穿戴设备上的应用促进了全固态离子选择性电极的发展.本文综述了全固态离子选择性电极的研究进展,包括传统的电位响应机理(氧化还原电容和双电层电容原理)和新型固接层材料(导电聚合物、碳和其他纳米材料)以及在可穿戴柔性传感器方面的应用.最后对全固态离子选择性电极存在的挑战和未来的前景做出了展望.

硼掺杂石墨烯耦合双金属氧化物作为高效氧气析出电催化剂

开发高效价廉的氧气析出反应电催化剂对于制备多种可再生能量转化和存储器件至关重要.本文中,我们设计合成了一系列硼掺杂石墨烯负载的钴镍双金属氧化物,并研究了其氧气析出电催化性能.研究结果表明适当温度下退火后的Co-Ni-Ox/BG(Co/Ni比为1:1)在碱性条件下表现出非常高的氧气析出电催化性能.在电流密度为10 mA cm-2时,该电催化剂对氧气析出反应的过电位仅为310 mV,优于绝大多数已报道的基于单金属氧化物的催化剂,甚至可与商业RuO2电催化剂的性能相媲美.该双金属氧化物复合材料中,电荷分布的微调控及协同耦合效应都对该材料的电催化性能起到了促进作用.另外,本文还提出了几种可有效提高氧化物材料氧气析出电催化活性的方法.

Single-phase La_(0.8)Sr_(0.2)Co_(1-x)Mn_(x)O_(3-δ) electrocatalyst as a triple H^(+)/O^(2-)/e^(-) conductor enabling high-performance intermediate-temperature water electrolysis

Hydrogen,especially the“green hydrogen”based on water electrolysis,is of great importance to build a sustainable society due to its high-energy-density,zero-carbon-emission features,and wide-range applications.Today's water electrolysis is usually carried out in either low-temperature(<100℃),e.g.,alkaline electrolyzer,or high-temperature(>700℃)applications,e.g.,solid oxide electrolyzer.However,the low-temperature devices usually suffer from high applied voltages(usually>1.5 V@0.01 A cm^(-2))and high cost;meanwhile,the high-temperature ones have an unsatisfied lifetime partially due to the incompatibility among components.Reasonably,an intermediate-temperature device,namely,proton ceramic cell(PCC),has been recently proposed.The widely-used air electrode for PCC is based on double O^(2-)/e^(-)conductor or composited O^(2-)/e^(-)-H^(+)conductor,limiting the accessible reaction region.Herein,we designed a single-phase La_(0.8)Sr_(0.2)Co_(1-x)Mn_(x)O_(3-δ)(LSCM)with triple H^(+)/O^(2-)/e^(-)conductivity as the air electrode for PCCs.Specifically,the La_(0.8)Sr_(0.2)Co_(0.8)Mn_(0.2)O_(3-δ)(LSCM8282)incorporates 5.8%proton carriers in molar fraction at 400℃,indicating superior proton conducting ability.Impressively,a high current density of 1580 mA cm^(-2) for hydrogen production(water electrolysis)is achieved at 1.3 V and 650℃,surpassing most low-and high-temperature devices reported so far.Meanwhile,such a PCC can also be operated under a reversible fuel cell mode,with a peak power density of 521 mW cm^(-2) at 650℃.By correlating the electrochemical performances with the hydrated proton concentration of single-phase triple conducting air electrodes in this work and our previous work,a principle for rational design of high-performance PCCs is proposed.

Adsorption and desorption mechanisms on graphene oxide nanosheets: Kinetics and tuning

A knowledge of the adsorption and desorption behavior of sorbates on surface adsorptive site(SAS)is the key to optimizing the chemical reactivity of catalysts.However,direct identification of the chemical reactivity of SASs is still a challenge due to the limitations of characterization techniques.Here,we present a new pathway to determine the kinetics of adsorption/desorption on SASs of graphene oxide(GO)based on total internal reflectance fluorescence microscopy.The switching on and off of the fluorescent signal of SAS lit by carbon dots(CDs)was used to trace the adsorption process and desorption process.We find that sodium pyrophosphate(PPi)could increase the adsorption equilibrium of CDs thermodynamically and promote the substrate-assisted desorption pathway kinetically.At the single turnover level,it was disclosed that the species that can promote desorption may also be an adsorption promoter.Such discovery provides significant guidance for improving the chemical reactivity of the heterogeneous catalyst.