Bridging the Gap between Nonliving Matter and Cellular Life

A cell, the fundamental unit of life, contains the requisite blueprint information necessary to survive and to build tissues, organs, and systems, eventually forming a fully functional living creature. A slight structural alteration can result in data misprinting, throwing the entire life process off balance. Advances in synthetic biology and cell engineering enable the predictable redesign of biological systems to perform novel functions. Individual functions and fundamental processes at the core of the biology of cells can be investigated by employing a synthetically constrained micro or nanoreactor. However, constructing a life-like structure from nonliving building blocks remains a considerable challenge. Chemical compartments, cascade signaling, energy generation, growth, replication, and adaptation within micro or nanoreactors must be comparable with their biological counterparts. Although these reactors currently lack the power and behavioral sophistication of their biological equivalents, their interface with biological systems enables the development of hybrid solutions for real-world applications, such as therapeutic agents, biosensors, innovative materials, and biochemical microreactors. This review discusses the latest advances in cell membrane-engineered micro or nanoreactors, as well as the limitations associated with high-throughput preparation methods and biological applications for the real-time modulation of complex pathological states.     

Applications of irreversible thermodynamics to rapid solidification of multicomponent alloys

Abstract

Solidification, as the key step in physical metallurgy, plays a decisive role in tuning the various properties of materials. From a thermodynamic perspective, the solidification processes can be considered as the evolution of non-equilibrium systems, where the metastable melts become the stable solids with lower free energy. In contrast to equilibrium thermodynamics, which focus on the static equilibrium states, irreversible thermodynamics is a powerful tool to describe the evolution of non-equilibrium systems and has been successfully applied to various fields in materials science. In the present paper, we review the basic philosophy for the phenomenological irreversible thermodynamics, the methods to obtain the governing equations for the evolution of multicomponent solidifying systems and the potential applications to other metallurgical phenomena.     

Interface Engineering in Multiphase Systems toward Synthetic Cells and Organelles: From Soft Matter Fundamentals to Biomedical Applications

Synthetic cells have a major role in gaining insight into the complex biological processes of living cells; they also give rise to a range of emerging applications from gene delivery to enzymatic nanoreactors. Living cells rely on compartmentalization to orchestrate reaction networks for specialized and coordinated functions. Principally, the compartmentalization has been an essential engineering theme in constructing cell-mimicking systems. Here, efforts to engineer liquid–liquid interfaces of multiphase systems into membrane-bounded and membraneless compartments, which include lipid vesicles, polymer vesicles, colloidosomes, hybrids, and coacervate droplets, are summarized. Examples are provided of how these compartments are designed to imitate biological behaviors or machinery, including molecule trafficking, growth, fusion, energy conversion, intercellular communication, and adaptivity. Subsequently, the state-of-art applications of these cell-inspired synthetic compartments are discussed. Apart from being simplified and cell models for bridging the gap between nonliving matter and cellular life, synthetic compartments also are utilized as intracellular delivery vehicles for nuclei acids and nanoreactors for biochemical synthesis. Finally, key challenges and future directions for achieving the full potential of synthetic cells are highlighted.     

High power rechargeable batteries

Energy and power density are the key figures of merit for most electrochemical energy storage systems. Considerable efforts worldwide have been made to improve the energy density of rechargeable (secondary) batteries, as this is critical for most applications. As the penetration of batteries into ever more demanding applications has increased, power density, the allowed rate of energy transfer per unit volume or mass, is becoming equally important. High power density batteries have the potential to be rapidly charged, possibly in a few minutes or less, and can also deliver high peak discharge powers. Normally increases in power density are only possible through significant reductions in energy density, however emerging materials research is showing this needs not to be the case. Here we discuss emerging concepts in high power batteries, with a particular focus on Li-ion based chemistries.     

Cold atmospheric plasma: Sources, processes, and applications

Atmospheric pressure gas discharge plasmas, especially those operated at energy non-equilibrium and low gas temperatures, have recently become a subject of great interest for a wide variety of technologies including surface treatment and thin-film deposition. A driving force for these developments is the avoidance of expensive equipment required for competing vacuum-based plasma technologies. Although there are many applications where non-equilibrium (cold) plasma at atmospheric and higher pressures represents a substantial advantage, there are also a number of applications where low-pressure plasmas simply cannot be replaced due to specific properties and limitations of the atmospheric plasma and related equipment. In this critical review, the primary principles and characteristics of the cold atmospheric plasma and differences from vacuum-based plasma processes are described and discussed to provide a better understanding of the capabilities and limits of emerging atmospheric plasma technologies.     

Order-disorder behavior at thin film oxide interfaces

Order-disorder processes fundamentally determine the structure and properties of many important oxide systems for energy and computing applications. While these processes have been intensively studied in bulk materials, they are less investigated and understood for nanostructured oxides in highly non-equilibrium conditions. These systems can now be realized through a range of deposition techniques and probed at exceptional spatial and chemical resolution, leading to a greater focus on interface dynamics. Here we survey a selection of recent studies of order-disorder behavior at thin film oxide interfaces, with a particular emphasis on the emergence of order during synthesis and disorder in extreme irradiation environments. We summarize key trends and identify directions for future study in this growing research area.     

Nanoelectronic programmable synapses based on phase change materials for brain-inspired computing

Brain-inspired computing is an emerging field, which aims to extend the capabilities of information technology beyond digital logic. A compact nanoscale device, emulating biological synapses, is needed as the building block for brain-like computational systems. Here, we report a new nanoscale electronic synapse based on technologically mature phase change materials employed in optical data storage and nonvolatile memory applications. We utilize continuous resistance transitions in phase change materials to mimic the analog nature of biological synapses, enabling the implementation of a synaptic learning rule. We demonstrate different forms of spike-timing-dependent plasticity using the same nanoscale synapse with picojoule level energy consumption.     

Emerging Trends in Information‐Driven Engineering of Complex Biological Systems

Synthetic biological systems are used for a myriad of applications, including tissue engineered constructs for in vivo use and microengineered devices for in vitro testing. Recent advances in engineering complex biological systems have been fueled by opportunities arising from the combination of bioinspired materials with biological and computational tools. Driven by the availability of large datasets in the “omics” era of biology, the design of the next generation of tissue equivalents will have to integrate information from single‐cell behavior to whole organ architecture. Herein, recent trends in combining multiscale processes to enable the design of the next generation of biomaterials are discussed. Any successful microprocessing pipeline must be able to integrate hierarchical sets of information to capture key aspects of functional tissue equivalents. Micro‐ and biofabrication techniques that facilitate hierarchical control as well as emerging polymer candidates used in these technologies are also reviewed.     

In Situ Transmission Electron Microscopy for Energy Materials and Devices

Energy devices such as rechargeable batteries, fuel cells, and solar cells are central to powering a renewable, mobile, and electrified future. To advance these devices requires a fundamental understanding of the complex chemical reactions, material transformations, and charge flow that are associated with energy conversion processes. Analytical in situ transmission electron microscopy (TEM) offers a powerful tool for directly visualizing these complex processes at the atomic scale in real time and in operando. Recent advancements in energy materials and devices that have been enabled by in situ TEM are reviewed. First, the evolutionary development of TEM nanocells from the open‐cell configuration to the closed‐cell, and finally the full‐cell, is reviewed. Next, in situ TEM studies of rechargeable ion batteries in a practical operation environment are explored, followed by applications of in situ TEM for direct observation of electrocatalyst formation, evolution, and degradation in proton‐exchange membrane fuel cells, and fundamental investigations of new energy materials such as perovskites for solar cells. Finally, recent advances in the use of environmental TEM and cryogenic electron microscopy in probing clean‐energy materials are presented and emerging opportunities and challenges in in situ TEM research of energy materials and devices are discussed.     

Advances in science and technology of modern energetic materials: an overview

Energetic materials such as explosives, propellants and pyrotechnics are widely used for both civilian and military explosives applications. The present review focuses briefly on the synthesis aspects and some of the physico-chemical properties of energetic materials of the class: (a) aminopyridine-N-oxides, (b) energetic azides, (c) high nitrogen content energetic materials, (d) imidazoles, (e) insensitive energetic materials, (f) oxidizers, (g) nitramines, (h) nitrate esters and (i) thermally stable explosives. A brief comment is also made on the emerging nitration concepts. This paper also reviews work done on primary explosives of current and futuristic interest based on energetic co-ordination compounds. Lead-free co-ordination compounds are the candidates of tomorrow's choice in view of their additional advantage of being eco-friendly. Another desirable attribute of lead free class of energetic compounds is the presence of almost equivalent quantity of fuel and oxidizer moieties. These compounds may find wide spectrum of futuristic applications in the area of energetic materials. The over all aim of the high energy materials research community is to develop the more powerful energetic materials/explosive formulations/propellant formulations in comparison to currently known benchmark materials/compositions. Therefore, an attempt is also made to highlight the important contributions made by the various researchers in the frontier areas energetic ballistic modifiers, energetic binders and energetic plasticizers.     

Controlling biomolecular condensates via chemical reactions

Biomolecular condensates are small droplets forming spontaneously in biological cells through phase separation. They play a role in many cellular processes, but it is unclear how cells control them. Cellular regulation often relies on post-translational modifications of proteins. For biomolecular condensates, such chemical modifications could alter the molecular interaction of key condensate components. Here, we test this idea using a theoretical model based on non-equilibrium thermodynamics. In particular, we describe the chemical reactions using transition-state theory, which accounts for the non-ideality of phase separation. We identify that fast control, as in cell signalling, is only possible when external energy input drives the reaction out of equilibrium. If this reaction differs inside and outside the droplet, it is even possible to control droplet sizes. Such an imbalance in the reaction could be created by enzymes localizing to the droplet. Since this situation is typical inside cells, we speculate that our proposed mechanism is used to stabilize multiple droplets with independently controlled size and count. Our model provides a novel and thermodynamically consistent framework for describing droplets subject to non-equilibrium chemical reactions.     

Intelligent systems using triboelectric,piezoelectric, and pyroelectric nanogenerators

Recent advances in artificial intelligence, computer science, communication, sensing and actuation technologies have resulted in the development of several novel intelligent systems. At the same time, the emergence of nanogenerators has opened a new research avenue with the overarching goal of developing self-powered sensing systems. The concepts of self-powered sensing, based on nanogenerators and intelligent systems can be fused together to open a new area of interdisciplinary research. In this article, we aim to show how these two emerging technologies have been combined to develop self-powered intelligent sensing systems. We first focus on the main keywords in the area of nanogenerators. Keyword co-occurrence network graphs are generated based on the most used keywords in the area of nanogenerators to select key concepts that are directly connected to the concept of intelligent systems. Thus, a detailed review is provided on different intelligent self-powered sensing systems based on nanogenerators. We also discuss the challenges presented by combining intelligent systems and self-powered sensing. As most of intelligent devices rely on machine learning techniques, a comprehensive section is allocated to this topic to focus on its applications in nanogenerator-based devices.     

Nanostructured electrodes for lithium-ion and lithium-air batteries: the latest developments, challenges, and perspectives

The urgency for clean and secure energy has stimulated a global resurgence in searching for advanced electrical energy storage systems. For now and the foreseeable future, batteries remain the most promising electrical energy storage systems for many applications, from portable electronics to emerging technologies such as electric vehicles and smart grids, by potentially offering significantly improved performance, energy efficiencies, reliability, and energy security while also permitting a drastic reduction in fuel consumption and emissions. The energy and power storage characteristics of batteries critically impact the commercial viability of these emerging technologies. For example, the realization of electric vehicles hinges on the availability of batteries with significantly improved energy and power density, durability, and reduced cost. Further, the design, performance, portability, and innovation of many portable electronics are limited severely by the size, power, and cycle life of the existing batteries. Creation of nanostructured electrode materials represents one of the most attractive strategies to dramatically enhance battery performance, including capacity, rate capability, cycling life, and safety. This review aims at providing the reader with an understanding of the critical scientific challenges facing the development of advanced batteries, various unique attributes of nanostructures or nano-architectures applicable to lithium-ion and lithium-air batteries, the latest developments in novel synthesis and fabrication procedures, the unique capabilities of some powerful, in situ characterization techniques vital to unraveling the mechanisms of charge and mass transport processes associated with battery performance, and the outlook for future-generation batteries that exploit nanoscale materials for significantly improved performance to meet the ever-increasing demands of emerging technologies.     

Design,fabrication and applications of soft network materials

Soft network materials represent a class of emerging cellular materials that have well-organized micro-architectures inspired by network microstructures found in many soft biological tissues. Apart from a good combination of low density, high stretchability and high air permeability, the high degree of design flexibility of soft network materials allows precise customization of mechanical properties by rationally tailoring their microstructural architecture and optimizing selections of constituent materials. These intriguing properties have enabled a range of promising applications in cutting-edge technologies, such as bio-integrated electronics and regenerative medicine. This review summarizes the latest progress in the design and fabrication of soft network materials, as well as their representative applications in biomedical devices, tissue engineering and other areas. It focuses on fundamental principles, design concepts and fabrication techniques of soft network materials that consist of either periodically or randomly distributed microstructures. Rational designs of these soft network materials result in customized mechanical properties that mimic or even exceed those of soft biological tissues. Finally, perspectives on the remaining challenges and open opportunities are provided.     

Advanced Photonic Processes for Photovoltaic and Energy Storage Systems

Solar‐energy harvesting through photovoltaic (PV) conversion is the most promising technology for long‐term renewable energy production. At the same time, significant progress has been made in the development of energy‐storage (ES) systems, which are essential components within the cycle of energy generation, transmission, and usage. Toward commercial applications, the enhancement of the performance and competitiveness of PV and ES systems requires the adoption of precise, but simple and low‐cost manufacturing solutions, compatible with large‐scale and high‐throughput production lines. Photonic processes enable cost‐efficient, noncontact, highly precise, and selective engineering of materials via photothermal, photochemical, or photophysical routes. Laser‐based processes, in particular, provide access to a plethora of processing parameters that can be tuned with a remarkably high degree of precision to enable innovative processing routes that cannot be attained by conventional approaches. The focus here is on the application of advanced light‐driven approaches for the fabrication, as well as the synthesis, of materials and components relevant to PV and ES systems. Besides presenting recent advances on recent achievements, the existing limitations are outlined and future possibilities and emerging prospects discussed.     

Electron microscopy of specimens in liquid

Imaging samples in liquids with electron microscopy can provide unique insights into biological systems, such as cells containing labelled proteins, and into processes of importance in materials science, such as nanoparticle synthesis and electrochemical deposition. Here we review recent progress in the use of electron microscopy in liquids and its applications. We examine the experimental challenges involved and the resolution that can be achieved with different forms of the technique. We conclude by assessing the potential role that electron microscopy of liquid samples can play in areas such as energy storage and bioimaging.     

Nature-inspired calcium phosphate coatings: present status and novel advances in the science of mimicry

There has been a growing awareness in materials science that the adaptation of nature biological processes can lead to significant progresses in the controlled fabrication of advanced materials for an all range of applications. To learn from, understand and apply these natural processes for producing calcium phosphate coatings that are biologically similar to bone apatite, mimicking its properties, has driven the attention of many researchers in recent years. This article reviews the most relevant advances in this emerging research field, pointing out several approaches being introduced and explored by distinct laboratories.     

SAHPPA: a novel power pinch analysis approach for the design of off-grid hybrid energy systems

This work proposes a novel approach called stand-alone hybrid system power pinch analysis (SAHPPA), which is particularly applicable for the design of off-grid distributed energy generation systems. The enhanced graphical tool employs new ways of utilising the recently introduced demand composite curve and supply composite curve while honouring and adapting fundamental energy systems engineering concepts. The SAHPPA method is capable of optimising the capacity of both the power generators and energy storage for biomass (i.e. non-intermittent) and solar photovoltaic (i.e. intermittent) energy technologies, which is a contribution to the emerging area of power pinch analysis. In addition, the procedure considers all possible efficiency losses in the overall system encompassing the charging–discharging and current inversion processes.     

Flashlight-material interaction for wearable and flexible electronics

Light-material interaction has received significant attention for wearable electronics because of its exceptional ability to excite multi-physical, transient, and non-equilibrium photon interactions in a spatiotemporally controlled manner. It has realized unique photothermal and photochemical reactions with various types of materials, including metal nanomaterials, ceramics, graphene, polymers, and perovskites, enabling the substantial performance improvement of soft electronics without damaging a temperature-sensitive substrates. Among the numerous optical sources, flash lamps have been considered to be a suitable platform for commercial applications owing to their excellent light-output efficiency, rapid processing capability, and outstanding compatibility with large-scale roll-to-roll manufacturing. These exclusive features offer considerable advantages in a broad range of wearable and flexible electronics such as solar cells, thin-film-transistors, optoelectronics, and sensors on polymer substrates compared to the conventional high-temperature microfabrication processes. The flash lamp technology has consistently advanced to provide novel concepts of nanomaterials/devices with unlimited form factors and strategies for future wearable electronics. Here, the recent progress in the field of flashlight-material interaction for soft electronics is summarized with regard to the process parameters, materials, and devices, together with the latest updates on the flash lamp technology.