Preface 1.General Considerations 2.Basic Processes in Atomization 3.Drop Size Distributions of Sprays 4.Atomizers 5.Flow in Atomizers 6.Atomizer Performance 7.External Spray Charcteristics 8.Drop Evaporation 9.Drop Sizing Methods Index

Atomization and Sprays

Energy storage devices that can deliver high powers have many applications, including hybrid vehicles and renewable energy. Much research has focused on increasing the power output of lithium batteries by reducing lithium-ion diffusion distances, but outputs remain far below those of electrochemical capacitors and below the levels required for many applications. Here, we report an alternative approach based on the redox reactions of functional groups on the surfaces of carbon nanotubes. Layer-by-layer techniques are used to assemble an electrode that consists of additive-free, densely packed and functionalized multiwalled carbon nanotubes. The electrode, which is several micrometres thick, can store lithium up to a reversible gravimetric capacity of approximately 200 mA h g(-1)(electrode) while also delivering 100 kW kg(electrode)(-1) of power and providing lifetimes in excess of thousands of cycles, both of which are comparable to electrochemical capacitor electrodes. A device using the nanotube electrode as the positive electrode and lithium titanium oxide as a negative electrode had a gravimetric energy approximately 5 times higher than conventional electrochemical capacitors and power delivery approximately 10 times higher than conventional lithium-ion batteries.

High-Power Lithium Batteries from Functionalized Carbon Nanotube Electrodes

Recent progress in electronic skin or e-skin research is broadly reviewed, focusing on technologies needed in three main applications: skin-attachable electronics, robotics, and prosthetics. First, since e-skin will be exposed to prolonged stresses of various kinds and needs to be conformally adhered to irregularly shaped surfaces, materials with intrinsic stretchability and self-healing properties are of great importance. Second, tactile sensing capability such as the detection of pressure, strain, slip, force vector, and temperature are important for health monitoring in skin attachable devices, and to enable object manipulation and detection of surrounding environment for robotics and prosthetics. For skin attachable devices, chemical and electrophysiological sensing and wireless signal communication are of high significance to fully gauge the state of health of users and to ensure user comfort. For robotics and prosthetics, large-area integration on 3D surfaces in a facile and scalable manner is critical. Furthermore, new signal processing strategies using neuromorphic devices are needed to efficiently process tactile information in a parallel and low power manner. For prosthetics, neural interfacing electrodes are of high importance. These topics are discussed, focusing on progress, current challenges, and future prospects.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/adma.201904765

Electronic Skin: Recent Progress and Future Prospects for Skin‐Attachable Devices for Health Monitoring, Robotics, and Prosthetics

Bio-integrated wearable systems can measure a broad range of biophysical, biochemical, and environmental signals to provide critical insights into overall health status and to quantify human performance. Recent advances in material science, chemical analysis techniques, device designs, and assembly methods form the foundations for a uniquely differentiated type of wearable technology, characterized by noninvasive, intimate integration with the soft, curved, time-dynamic surfaces of the body. This review summarizes the latest advances in this emerging field of “bio-integrated” technologies in a comprehensive manner that connects fundamental developments in chemistry, material science, and engineering with sensing technologies that have the potential for widespread deployment and societal benefit in human health care. An introduction to the chemistries and materials for the active components of these systems contextualizes essential design considerations for sensors and associated platforms that appear in f...

Bio-Integrated Wearable Systems: A Comprehensive Review

Hybrid metal-ion capacitors (MICs) (M stands for Li or Na) are designed to deliver high energy density, rapid energy delivery, and long lifespan. The devices are composed of a battery anode and a supercapacitor cathode, and thus become a tradeoff between batteries and supercapacitors. In the past two decades, tremendous efforts have been put into the search for suitable electrode materials to overcome the kinetic imbalance between the battery-type anode and the capacitor-type cathode. Recently, some transition-metal compounds have been found to show pseudocapacitive characteristics in a nonaqueous electrolyte, which makes them interesting high-rate candidates for hybrid MIC anodes. Here, the material design strategies in Li-ion and Na-ion capacitors are summarized, with a focus on pseudocapacitive oxide anodes (Nb2 O5 , MoO3 , etc.), which provide a new opportunity to obtain a higher power density of the hybrid devices. The application of Mxene as an anode material of MICs is also discussed. A perspective to the future research of MICs toward practical applications is proposed to close.

Nonaqueous Hybrid Lithium-Ion and Sodium-Ion Capacitors

Extremely stretchable self-healing strain sensors based on conductive hydrogels are successfully fabricated. The strain sensor can achieve autonomic self-heal electrically and mechanically under ambient conditions, and can sustain extreme elastic strain (1000%) with high gauge factor of 1.51. Furthermore, the strain sensors have good response, signal stability, and repeatability under various human motion detections.

/pdf/extremely-stretchable-strain-sensors-based-on-conductive-37zv95vw64.pdf

Extremely Stretchable Strain Sensors Based on Conductive Self-Healing Dynamic Cross-Links Hydrogels for Human-Motion Detection.

Rational Design of Nanostructured Electrode Materials toward Multifunctional Supercapacitors

Stretchable conductors are vital and indispensable components in soft electronic systems. The development for stretchable conductors has been highly motivated with different approaches established to address the dilemma in the conductivity and stretchability trade-offs to some extent. Here, a new strategy to achieve superelastic conductors with high conductivity and stable electrical performance under stretching is reported. It is demonstrated that by electrically anchoring conductive fillers with eutectic gallium indium particles (EGaInPs), significant improvement in stretchability and durability can be achieved in stretchable conductors. Different from the strategy of modulating the chemical interactions between the conductive fillers and host polymers, the EGaInPs provide dynamic and robust electrical anchors between the conductive fillers. A superelastic conductor which can achieve a high stretchability with 1000% strain at initial conductivity of 8331 S cm-1 and excellent cycling durability with about eight times resistance change (compared to the initial resistance at 0% strain before stretching) after reversibly stretching to 800% strain for 10 000 times is demonstrated. Applications of the superelastic conductor in an interactive soft touch device and a stretchable light-emitting system are also demonstrated, featuring its promising applications in soft robotics or soft and interactive human-machine interfaces.

Printable Superelastic Conductors with Extreme Stretchability and Robust Cycling Endurance Enabled by Liquid‐Metal Particles

Stretchable and self-healing (SH) energy storage devices are indispensable elements in energy-autonomous electronic skin. However, the current collectors are not self-healable nor intrinsically stretchable, they mostly rely on strain-accommodating structures that require complex processing, are often limited in stretchability, and suffer from low device packing density and fragility. Here, an SH conductor comprising nickel flakes, eutectic gallium indium particles (EGaInPs), and carboxylated polyurethane (CPU) is presented. An energy storage device is constructed by the two SH electrodes assembled with graphene nanoplatelets sandwiching an ionic-liquid electrolyte. An excellent electrochemical healability (94% capacity retention upon restretching at 100% after healing from bifurcation) is unveiled, stemming from the complexation modulated redox behavior of EGaIn in the presence of the ligand bis(trifluoromethanesulfonyl)imide, which enhances the reversible Faradaic reaction of Ga. Self-healing can be achieved where the damaged regions are electrically restored by the flow of liquid metal and mechanically healing activated by the interfacial hydrogen bonding of CPU with an efficiency of 97.5% can be achieved. The SH conductor has an initial conductivity of 2479 S cm-1 that attains a high stretchability with 700% strain, it restores 100% stretchability even after breaking/healing with the electrical healing efficiency of 75%.

A Stretchable and Self-Healing Energy Storage Device Based on Mechanically and Electrically Restorative Liquid-Metal Particles and Carboxylated Polyurethane Composites

Sodium ion battery (SIB) as a next-generation battery has been drawing much attention due to the abundance and even distribution of sodium source Metal sulfides with high theoretical capacity and good electrical conductivity are promising anode candidates for SIB, however, the structural collapse caused by severe volume change during the de/sodiation process typically results in a fast capacity decay, limited rate capability, and cycling stability In this work, by careful composition and structure design, polydopamine coated Prussian blue analogs derived carbon coated bimetallic sulfide hollow nanocubes (PBCS) are prepared with distinguished morphology, higher surface area, smaller charge transfer resistance, and higher sodium diffusion coefficient than the uncoated bimetallic sulfides An optimum carbon coated bimetallic sulfide hollow nanocube anode delivers a specific capacity of ≈500 mA h g−1 at 50 mA g−1 with ethylene carbonate/dimethyl carbonate (1:1, vol%) electrolyte in the presence of fluoroethylene carbonate additives A capacity of 1223 mA h g−1 can be realized at 5000 mA g−1, showing good rate performance In addition the carbon coated bimetallic sulfide hollow nanocubes can maintain capacity of 87 mA h g−1 after being cycled at 500 mA g−1 for 150 times, indicating its good cycling stability The structure integrity, high specific capacity, good rate performance, and cycling stability of PBCS render it a promising anode material for advanced SIB

Shaohui Li

Papers

Extremely Stretchable Strain Sensors Based on Conductive Self-Healing Dynamic Cross-Links Hydrogels for Human-Motion Detection.

Rational Design of Nanostructured Electrode Materials toward Multifunctional Supercapacitors

Printable Superelastic Conductors with Extreme Stretchability and Robust Cycling Endurance Enabled by Liquid‐Metal Particles

A Stretchable and Self-Healing Energy Storage Device Based on Mechanically and Electrically Restorative Liquid-Metal Particles and Carboxylated Polyurethane Composites

Carbon Coated Bimetallic Sulfide Hollow Nanocubes as Advanced Sodium Ion Battery Anode