Autonomous Chemistry Enabling Environment-Adaptive Electrochemical Energy Storage Devices

Next-generation electronics that are fused into the human body can play a key role in future intelligent communication,smart healthcare,and human enhancement applications.As a promising energy supply component for smart biointegrated electronics,environment-adaptive electrochemical energy storage(EES)devices with complementary adaptability and functions have garnered huge interest in the past decade.Owing to the advancements in autonomous chemistry,which regulate the constitutional dynamic networks in materials,EES devices have witnessed higher freedom of autonomous adaptability in terms of mechano-adaptable,biocompatibility,and stimuli-response properties for biointegrated and smart applications.In this mini-review,we summarize the recent progress in emerging environmentadaptive EES devices enabled by the constitutional dynamic network of mechanical adaptable materials,biocompatible materials,and stimuli-responsive supramolecular polymer materials.Finally,the challenges and perspectives of autonomous chemistry on the environment-adaptive EES devices are discussed.

Assemblies and composites of gold nanostructures for functional devices

Gold has been one of the most vastly used noble metals due to its unique properties.In modern manufacturing,gold is extensively used in electronics industry as electrical connectors due to the high conductivity and corrosion resistance.With advancements in gold chemistry and nanofabrication technologies,gold materials can be tailored down to the dimension of nanoscale,which enables various novel properties.However,it is still a huge challenge to realize practical functional devices by rational utilizing these gold nanostructures-based materials.Herein,the recent developments in the design and fabrication of various functional devices based on assemblies and composites of gold nanostructures are summarized.Starting from the plasmonic effect,optical colorimetric sensors,optoelectronics and surface-enhanced Raman spectroscopy sensors are introduced.Followed by conductive devices with novel properties,flexible transparent conductors,stretchable electronics,wearable and implantable devices are discussed.Both bottom-up and top-down approaches to prepare assemblies and composites are covered.In addition,the challenges and future developments in the field are also addressed.It is believed that further developments in gold nanostructures-based materials will greatly contribute to the nextgeneration biosensors,optoelectronics,wearable and implantable electronics.

Artificial interphase engineering of electrode materials to improve the overall performance of lithium-ion batteries

The overall performance of lithium-ion batteries （LIBs） is closely related to the interphase between the electrode materials and electrolytes. During LIB operation, electrolytes may decompose on the surface of electrode materials, forming a solid electrolyte interphase （SEI） layer. Ideally, the SEI layer should ensure reversible lithium-ion intercalation in the electrodes and suppress interfacial interactions. However, the chemical and mechanical stabilities of the SEI layer are not usually able to meet these requirements. Alternatively, tremendous efforts have been devoted to engineering the surface of electrode materials with an artificial interphase, which shows great promise in improving the electrochemical performance. Herein, we present a comprehensive summary of the state-of-the-art knowledge on this topic. The effects of the arrifidal interphase on the electrochemical performance of the electrode materials are discussed in detail. In particular, we highlight the importance of three functions of artificial interphases, including inhibiting electrolyte decomposition, protecting the electrodes from corrosion, and accommodatinz electrode volume chanzes.

An atomistic model of silk protein network for studying the effect of pre-stretching on the mechanical performances of silks

Silk protein builds one of the strongest natural fibers based on its complex nanocomposite structures.However,the mechanical performance of silk protein,related to its molecular structure and packing is still elusive.In this study,we constructed an atomistic silk protein network model,which reproduces the extensive connection topology of silk protein with structure details of theβ-sheet crystallites and amorphous domains.With the silk protein network model,we investigated the structure evolution and stress distribution of silk protein under external loading.We found a pre-stretching treatment during the spinning process can improve the strength of silk protein.This treatment improves the properties of silk protein network,i.e.,increases the number of nodes and bridges,makes the nodes distributed homogeneously,and induces the bridges in the network well aligned to the loading direction,which is of great benefit to the mechanical performances of silk protein.Our study not only provides a realized atomistic model for silk protein network that well represents the structures and deformations of silk proteins under loading,but also gains deep insights into the mechanism how the pre-loading on silk proteins during spinning improves the mechanical properties of silk fibers.

Conformal electrodes for on-skin digitalization

On-skin digitalization,streamlining the concept of the“human to device to cyberspace”platform,has attracted great attention due to its vital function in remote medicine and human-cyber interfaces.Beyond traditional rigid electrodes,soft electrodes with conformal and comfortable interfaces are essential for long-term and high-fidelity signal acquisition.In addition,the on-skin data processing systems will get rid of complex cables toward a vision of fascinating form,being lightweight,skin-friendly and even imperceptible.Although numerous soft materials and devices with mechanical tolerance have been developed,the study of conformal electrodes and on-skin digital integrated systems are still in infancy.Here,the requirements and designs of conformal electrodes,the emerging opportunities and challenges from multichannel/multifunctional sensors to a whole new on-skin sensing platform are highlighted.

Marching towards flexible intelligent materials

Our society is transforming into more intelligent eco-systems that seamlessly merge human beings,machines,the internet,and energy.The unprecedented momentum in such dramatic transformation inevitably relies on innovation in smarter materials.Flexible intelligent materials are eagerly demanded in such evolution.Flexible intelligent materials are soft materials whose properties can be altered by external stimuli.

2D Material Chemistry:Graphdiyne-based Biochemical Sensing

The modern internet-of-things era has witnessed an increasing growth in the demand for advanced sensors to collect precise information.To meet this demand,extensive efforts have been devoted to exploring competent ma terials and designing rational architectures for the fabrication of sensing devices.Graphdiyne represents a promising material due to the attractive electronic.optical and electrochemical properties deriving from its unique molecular structure.In this review,we firstly provide the points of view on the architectures and work principles of the graph divnebased sensing devices with respect to resistive,electrochemical,photoelectrochemical and fluorescent catego ries.Secondly,we present the promising applications on biochemical sensing,such as the detection of DNA,micro-RNA,and glucose.Finally,the challenges and prospects of graphdivne-based biochemical sensing platforms are also discussed,in order to provide a cornerstone for understanding this rapidly developing area.

Decimal Solvent-Based High-Entropy Electrolyte Enabling the Extended Survival Temperature of Lithium-Ion Batteries to−130°C

Freezing and crystallization of commercial ethylene carbonate-based binary electrolytes,leading to irreversible damage to lithium-ion batteries(LIBs),remain a significant challenge for the survival of energy storage devices at extremely low temperatures(<−40°C).Herein,a decimal solvent-based high-entropy electrolyte is developed with an unprecedented low freezing point of−130°C to significantly extend the service temperature range of LIBs,far superior to−30°C of the commercial counterpart.Distinguished from conventional electrolytes,this molecularly disordered solvent mixture greatly suppresses the freezing crystallization of electrolytes,providing good protection for LIBs from possible mechanical damage at extremely low temperatures.Benefiting from this,our high-entropy electrolyte exhibits extraordinarily high ionic conductivity of 0.62 mS·cm−1 at−60°C,several orders of magnitude higher than the frozen commercial electrolytes.Impressively,LIBs utilizing decimal electrolytes can be charged and discharged even at an ultra-low temperature of−60°C,maintaining high capacity retention(∼80%at−40°C)as well as remarkable rate capability.This study provides design strategies of low-temperature electrolytes to extend the service temperature range of LIBs,creating a new avenue for improving the survival and operation of various energy storage systems under extreme environmental conditions.