Objects in all dimensions are subject to translational dynamism and dynamic mutual interactions, and the ability to exert control over these events is one of the keys to the synthesis of functional ...materials. For the development of materials with truly dynamic functionalities, a paradigm shift from “nanotechnology” to “nanoarchitectonics” is proposed, with the aim of design and preparation of functional materials through dynamic harmonization of atomic‐/molecular‐level manipulation and control, chemical nanofabrication, self‐organization, and field‐controlled organization. Here, various examples of dynamic functional materials are presented from the atom/molecular‐level to macroscopic dimensions. These systems, including atomic switches, molecular machines, molecular shuttles, motional crystals, metal–organic frameworks, layered assemblies, gels, supramolecular assemblies of biomaterials, DNA origami, hollow silica capsules, and mesoporous materials, are described according to their various dynamic functions, which include short‐term plasticity, long‐term potentiation, molecular manipulation, switchable catalysis, self‐healing properties, supramolecular chirality, morphological control, drug storage and release, light‐harvesting, mechanochemical transduction, molecular tuning molecular recognition, hand‐operated nanotechnology.
From atom to space, objects in all dimensions have their motional dynamism and dynamic mutual interactions. A novel paradigm, nanoarchitectonics, is proposed, which aims to architect functional materials through dynamic harmonization of atomic‐/molecular‐level manipulation and control, chemical nanofabrication, self‐organization, and field‐controlled organization. Various examples of dynamic functional materials are explained from the atom‐/molecular‐level to human motion size.
In situations of power outage or shortage, such as periods just following a seismic disaster, the only reliable power source available is the most fundamental of forces i.e., manual mechanical ...stimuli. Although there are many macroscopic mechanical tools, mechanical control of nanomaterials and nanosystems has not been an easy subject to develop even by using advanced nanotechnological concepts. However, this challenge has now become a hot topic and many new ideas and strategies have been proposed recently. This report summarizes recent research examples of mechanical control of nanomaterials and nanosystems. Creation of macroscopic mechanical outputs by efficient accumulation of molecular‐level phenomena is first briefly introduced. We will then introduce the main subject: control of molecular systems by macroscopic mechanical stimuli. The research described is categorized according to the respective areas of mechanical control of molecular structure, molecular orientation, molecular interaction including cleavage and healing, and biological and micron‐level phenomena. Finally, we will introduce two more advanced approaches, namely, mechanical strategies for microdevice fabrication and mechanical control of molecular machines. As mechanical forces are much more reliable and widely applicable than other stimuli, we believe that development of mechanically responsive nanomaterials and nanosystems will make a significant contribution to fundamental improvements in our lifestyles and help to maintain and stabilize our society.
This Progress Report summarizes examples on mechanical control of nanomaterials and nanosystems and mainly focuses on recent research in this field. Approaches to create macroscopic mechanical outputs upon accumulation of molecular‐level phenomena and controls of molecular systems by macroscopic mechanical stimuli are described. As mechanical forces are much reliable and widely applicable, we believe these efforts have significant contributions for improving our life.
Incorporation of non‐equilibrium actions in the sequence of self‐assembly processes would be an effective means to establish bio‐like high functionality hierarchical assemblies. As a novel ...methodology beyond self‐assembly, nanoarchitectonics, which has as its aim the fabrication of functional materials systems from nanoscopic units through the methodological fusion of nanotechnology with other scientific disciplines including organic synthesis, supramolecular chemistry, microfabrication, and bio‐process, has been applied to this strategy. The application of non‐equilibrium factors to conventional self‐assembly processes is discussed on the basis of examples of directed assembly, Langmuir–Blodgett assembly, and layer‐by‐layer assembly. In particular, examples of the fabrication of hierarchical functional structures using bio‐active components such as proteins or by the combination of bio‐components and two‐dimensional nanomaterials, are described. Methodologies described in this review article highlight possible approaches using the nanoarchitectonics concept beyond self‐assembly for creation of bio‐like higher functionalities and hierarchical structural organization.
Simple self‐assembly methods cannot be used to attain high‐level organizations such as those found in biological systems. The introduction of non‐equilibrium processes and harmonization of multiple actions is required. As a novel methodology beyond self‐assembly, nanoarchitectonics, whose main conceptual aim is the formation of functional materials from nanoscopic units through the fusion of different scientific disciplines, has been proposed for the creation of bio‐like high functionality hierarchically organized structures.
The development of science and technology of advanced materials using nanoscale units can be conducted by a novel concept involving combination of nanotechnology methodology with various research ...disciplines, especially supramolecular chemistry. The novel concept is called 'nanoarchitectonics' where self-assembly processes are crucial in many cases involving a wide range of component materials. This review of self-assembly processes re-examines recent progress in materials nanoarchitectonics. It is composed of three main sections: (1) the first short section describes typical examples of self-assembly research to outline the matters discussed in this review; (2) the second section summarizes self-assemblies at interfaces from general viewpoints; and (3) the final section is focused on self-assembly processes at interfaces. The examples presented demonstrate the strikingly wide range of possibilities and future potential of self-assembly processes and their important contribution to materials nanoarchitectonics. The research examples described in this review cover variously structured objects including molecular machines, molecular receptors, molecular pliers, molecular rotors, nanoparticles, nanosheets, nanotubes, nanowires, nanoflakes, nanocubes, nanodisks, nanoring, block copolymers, hyperbranched polymers, supramolecular polymers, supramolecular gels, liquid crystals, Langmuir monolayers, Langmuir-Blodgett films, self-assembled monolayers, thin films, layer-by-layer structures, breath figure motif structures, two-dimensional molecular patterns, fullerene crystals, metal-organic frameworks, coordination polymers, coordination capsules, porous carbon spheres, mesoporous materials, polynuclear catalysts, DNA origamis, transmembrane channels, peptide conjugates, and vesicles, as well as functional materials for sensing, surface-enhanced Raman spectroscopy, photovoltaics, charge transport, excitation energy transfer, light-harvesting, photocatalysts, field effect transistors, logic gates, organic semiconductors, thin-film-based devices, drug delivery, cell culture, supramolecular differentiation, molecular recognition, molecular tuning, and hand-operating (hand-operated) nanotechnology.
The Langmuir‐Blodgett (LB) technique is known as an elegant method for fabrication of well‐defined layered structures with molecular level precision. Since its discovery the LB method has made an ...indispensable contribution to surface science, physical chemistry, materials chemistry and nanotechnology. However, recent trends in research might suggest the decline of the LB method as alternate methods for film fabrication such as layer‐by‐layer (LbL) assembly have emerged. Is LB film technology obsolete? This review is presented in order to challenge this preposterous question. In this review, we summarize recent research on LB and related methods including (i) advanced design for LB films, (ii) LB film as a medium for supramolecular chemistry, (iii) LB technique for nanofabrication and (iv) LB involving advanced nanomaterials. Finally, a comparison between LB and LbL techniques is made. The latter reveals the crucial role played by LB techniques in basic surface science, current advanced material sciences and nanotechnologies.
Has the LB technique been superseded by LbL assembly? Is the LB procedure merely an anachronistic obsolete technique? Is LB not required if we have LbL? The simple answer to these questions is NO! In this review we re‐evaluate the true value of the LB technique by summarizing recent research examples where the LB technique has been indispensable.
Here comes the sun: By using a combined strategy of molecular engineering and cosensitization, impressively high Jsc and Voc values were achieved for porphyrin dyes, resulting in high photovoltaic ...efficiencies up to 11.5 %, a record for non‐ruthenium dye‐sensitized solar cells (DSSCs) with the I−/I3− electrolyte. The results provide insight into furthering the development of efficient DSSCs through synergistically enhanced photovoltage and photocurrent.
The application of traditional electrode materials for high‐performance capacitive deionization (CDI) has been persistently limited by their low charge‐storage capacities, excessive co‐ion expulsion ...and slow salt removal rates. Here we report a bottom‐up approach to the preparation of a two‐dimensional (2D) Ti3C2Tx MXene‐polydopamine heterostructure having ordered in‐plane mesochannels (denoted as mPDA/MXene). Interfacial self‐assembly of mesoporous polydopamine (mPDA) monolayers on MXene nanosheets leads to the mPDA/MXene heterostructure, which exhibits several unique features: (1) MXene undergoes reversible ion intercalation/deintercalation and possesses high conductivity; (2) mPDA layers establish redox capacitive characteristics and Na+ selectivity, and also help to prevent self‐stacking and oxidation of MXene; (3) in‐plane mesochannels enable the smooth transport of ions at the internal spaces of this stacked 2D material. When applied as an electrode material for CDI, mPDA/MXene nanosheets exhibit top‐level CDI performance and cycling stability compared to those of the so far reported 2D materials. Our study opens an avenue for the rational construction of MXene‐organic hybrid heterostructures, and further motivates the development of high‐performance CDI electrode materials.
This communication reports a bottom‐up approach to a two‐dimensional (2D) Ti3C2Tx MXene‐polydopamine heterostructure with ordered in‐plane cylindrical mesochannels. The resultant 2D heterostructure shows top‐level CDI performance in its application as electrode material for capacitive deionization.
Fabrication of ultrasmall functional machines and their integration within ultrasmall areas or volumes can be useful for creation of novel technologies. The ultimate goal of the development of ...ultrasmall machines and device systems is to construct functional structures where independent molecules operate as independent device components. To realize exotic functions, use of enzymes in device structures is an attractive solution because enzymes can be regarded as efficient machines possessing high reaction efficiencies and specificities and can operate even under ambient conditions. In this review, recent developments in enzyme immobilization for advanced functions including device applications are summarized from the viewpoint of micro/nano-level structural control, or nanoarchitectonics. Examples are roughly classified as organic soft matter, inorganic soft materials or integrated/organized media. Soft matter such as polymers and their hybrids provide a medium appropriate for entrapment and encapsulation of enzymes. In addition, self-immobilization based on self-assembly and array formation results in enzyme nanoarchitectures with soft functions. For the confinement of enzymes in nanospaces, hard inorganic mesoporous materials containing well-defined channels play an important role. Enzymes that are confined exhibit improved stability and controllable arrangement, which are useful for formation of functional relays and for their integration into artificial devices. Layer-by-layer assemblies as well as organized lipid assemblies such as Langmuir-Blodgett films are some of the best media for architecting controllable enzyme arrangements. The ultrathin forms of these films facilitate their connection with external devices such as electrodes and transistors. Artificial enzymes and enzyme-mimicking catalysts are finally briefly described as examples of enzyme functions involving non-biological materials. These systems may compensate for the drawbacks of natural enzymes, such as their instabilities under harsh conditions. We believe that enzymes and their mimics will be freely coupled, organized and integrated upon demand in near future technologies.
There is a growing interest in the development of dynamic adaptive biomaterials for regulation of cellular functions. However, existing materials are limited to two‐state switching of the ...presentation and removal of cell‐adhesive bioactive motifs that cannot emulate the native extracellular matrix (ECM) in vivo with continuously adjustable characteristics. Here, tunable adaptive materials composed of a protein monolayer assembled at a liquid–liquid interface are demonstrated, which adapt dynamically to cell traction forces. An ultrastructure transition from protein monolayer to hierarchical fiber occurs through interfacial jamming. Elongated fibronectin fibers promote formation of elongated focal adhesion structures, increase focal adhesion kinase activation, and enhance neuronal differentiation of stem cells. Cell traction force results in spatial rearrangement of ECM proteins, which feeds back to alter stem cell fate. The reported biomimetic adaptive liquid interface enables dynamic control of stem cell behavior and has potential translational applications.
An adaptive dynamic system is engineered from a protein monolayer assembled at the water–perfluorocarbon interface. The soft liquid interface, which adapts dynamically to cell‐generated forces, guides differentiation of stem cells, and has broad implications for tissue engineering and regenerative medicine applications.
Exploring a new-family of carbon-based desalinators to optimize their performances beyond the current commercial benchmark is of significance for the development of practically useful capacitive ...deionization (CDI) materials. Here, we have fabricated a hierarchically porous N,P-doped carbon-graphene 2D heterostructure (denoted NPC/rGO) by using metal-organic framework (MOF)-nanoparticle-driven assembly on graphene oxide (GO) nanosheets followed by stepwise pyrolysis and phosphorization procedures. The resulting NPC/rGO-based CDI desalinator exhibits ultrahigh deionization performance with a salt adsorption capacity of 39.34 mg g
−1
in a 1000 mg L
−1
NaCl solution at 1.2 V over 30 min with good cycling stability over 50 cycles. The excellent performance is attributed to the high specific surface area, high conductivity, favorable meso-/microporous structure together with nitrogen and phosphorus heteroatom co-doping, all of which are beneficial for the accommodation of ions and charge transport during the CDI process. More importantly, NPC/rGO exhibits a state-of-the-art CDI performance compared to the commercial benchmark and most of the previously reported carbon materials, highlighting the significance of the MOF nanoparticle-driven assembly strategy and graphene-carbon 2D heterostructures for CDI applications.
MOF nanoparticle-driven assembly on 2D nanosheets produces the graphene-carbon heterostructure with hierarchically-porous P,N-doped layered architecture.