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As one of the most delicate bioprocesses in nature, biosilicification is closely related to biosilica with various morphologies, and has provided abundant inspiration to materials synthesis. In the present study, to explore the biosilica formation process and fabricate silica with an exquisite microstructure for lithium-ion battery (LIB) electrodes, a bacterial phage (M13) is used as a biotemplate to synthesize silica with diverse morphologies: cylinders, hexagonal prisms, assemblies of smaller cylinders and nanowires. A facile ethanol bath method is conducted to coat the nanowires with nitrogen-containing carbon and carbon-coated SiO2 nanowires with mesochannels (C@msSiO2NWs) are first used as anode materials for LIBs. Attributed to the uniform carbon coating and parallel mesochannel structure, the electronic conductivity and capacity to accommodate volume variations were significantly improved. In the electrochemical performance test, the composites calcined at 750 °C (C@msSiO2NWs-750) show an impressive capacity of 653 mA h g−1 at a current density of 500 mA g−1 and stability (1000 cycles). In view of the electrochemical test outcomes, the preparation of a sophisticated structure with an outstanding potential is easily achieved via a biomimetic strategy.

Bioinspired hydrogels have promising prospects in applications such as wearable devices, human health monitoring equipment, and soft robots due to their multifunctional sensing properties resembling natural skin. However, the preparation of intelligent hydrogels that provide feedback on multiple electronic signals simultaneously, such as human skin receptors, when stimulated by external contact pressure remains a substantial challenge. In this study, we designed a bioinspired hydrogel with multiple conductive capabilities by incorporating carbon nanotubes into a chelate of calcium ions with polyacrylic acid and sodium alginate. The bioinspired hydrogel consolidates self-healing ability, stretchability, 3D printability, and multiple conductivities. It can be fabricated as an integrated strain sensor with simultaneous piezoresistive and piezocapacitive performances, exhibiting sensitive (gauge factor of 6.29 in resistance mode and 1.25 kPa-1 in capacitance mode) responses to subtle pressure changes in the human body, such as finger flexion, knee flexion, and respiration. Furthermore, the bioinspired strain sensor sensitively and discriminatively recognizes the signatures written on it. Hence, we expect our ideas to provide inspiration for studies exploring the use of advanced hydrogels in multifunctional skin-like smart wearable devices.

A living organism is a complex “biosynthesis factory” for the fabrication of materials under environmentally benign conditions, which is worth studying to extend synthesis techniques. Inspired by the formation process of pearls, living mussels have been used to direct the formation of nitrogen-doped anatase TiO2. Here, instead of only synthesizing single-phase materials, we extend the technique for the fabrication of a SnO2/graphene oxide composite. The tin chloride hydroxide hydrate precursor transforms into SnO2 nanocrystals in situ on the surface of graphene oxide with good dispersion and high load to form a homogeneous microstructure under the direction of mussels at ambient temperature. The SnO2/graphene oxide composite exhibits improved lithium storage performance as the anode of a lithium-ion battery. A stable reversible capacity can be achieved, which is up to 1099 mA h g−1 after 100 cycles at a current density of 100 mA g−1. This study demonstrates the possibility and practicability of synthesizing anthropogenically useful composite materials in living organisms, which is advantageous to extend synthesis methods and reduce energy consumption.

Collagen fibrils present periodic structures, which provide space for intrafibrillar growth of oriented hydroxyapatite nanocrystals in bone and contribute to the good mechanical properties of bone. However, there are not many reports focused on bioprocess-inspired synthesis of non-native inorganic materials inside collagen fibrils and detailed forming processes of crystals inside collagen fibrils remain poorly understood. Herein, the rapid intrafibrillar mineralization of calcium fluoride nanocrystals with a periodically patterned nanostructure is demonstrated. The negatively charged calcium fluoride precursor phase infiltrates collagen fibrils through the gap zones creating an intricate periodic mineralization pattern. Later, the nanocrystals initially filling the gap zones only expand gradually into the remaining space within the collagen fibrils. Mineralized tendons with organized calcium fluoride nanocrystals acquire mechanical properties (indentation elastic modulus ∼25.1 GPa and hardness ∼1.5 GPa) comparable or even superior to those of native human dentin and lamellar bone. Understanding the mineral growth processes in collagen may facilitate the development of tissue engineering and repairing.

The formation of natural structures found in biological systems is wonderful and can be completed at ambient temperatures in contrast to artificial technologies wherein harsh conditions are common prerequisites. A new research direction, "bioprocess inspired manufacturing", is proposed for fabricating advanced materials with novel structures and functions. Nacre consists of an ordered multilayer structure of crystalline calcium carbonate lamellae separated by organic layers exhibiting mechanical toughness, which transcends that of its constituent components. Inspired by the nacre formation process, a microscale additive manufacturing mineralization method is proposed for achieving a multilayered organic-inorganic layered structure. In this work, layered calcite was synthesized on the surface of chitosan (CS) films at room temperature under the coordinated control of magnesium ions (Mg2+) and polyacrylic acid (PAA). The CS films and layered calcite are sequentially assembled in a layer-by-layer deposition approach to form an organic-inorganic hybrid structure. The nacre-like chitosan/CaCO3 (CS/CaCO3) composites exhibit high transparency and underwater superoleophobicity. Impressively, the hardness (2.35 ± 0.03 GPa) and Young's modulus (58.1 ± 0.5 GPa) of the as-prepared (CS/CaCO3) composites are comparable to those of their biological counterparts. This study provides a rational bioprocess-inspired room-temperature mineralization method to develop advanced composite materials with good performance.

This study presents an innovative surface-diffusion mechanism for the growth of substrate-free and catalyst-free boron nitride nanosheets (BNNSs) by annealing an ammonium borate hydroxide hydrate precursor in a NH3 chemical vapor deposition system. At elevated temperatures, part of NH4B5O8 slowly decomposes and forms B2O3, and flowing NH3 gradually diffuses to the B2O3 surface to form vertically aligned BNNSs. The lateral dimension and crystallinity of the BNNSs increase, while their thickness decreases with the continuous surface-diffusion reaction. The residual NH4B5O8 and B2O3 absorbs moisture in the air to constitute NH4B5O8·4H2O and H3BO3 substrates. With increasing annealing temperature and soaking time (at 1400 °C for 7 h), all NH4B5O8 decomposes and the surface-diffusion reaction between B2O3 and NH3 completely occurs, forming substrate-free BNNSs with a lateral dimension of 1 μm and a thickness of 10 nm. This reliable approach for synthesizing BNNSs paves the way for future applications in advanced ceramic composites.

As environmental and energy problems have worsened worldwide, research for developing renewable energy has become urgent. Presently, the primary focus of such research is directed towards the photocatalytic decomposition of water to produce hydrogen as an energy source. Herein, ZnO nanosheet/CdS nanoparticle heterostructures were synthesized by a mild wet chemical reaction and displayed a high photocatalytic efficiency (1040 μmol g−1 h−1) without Pt loading under visible light radiation. The structure was prepared by first constructing two-dimensional nanocrystalline ZnO flowers and then loading CdS nanoparticles onto the nanocrystals. Results show that this structure can facilitate the separation of photogenerated electrons and holes and improve the photocatalytic efficiency and stability of the materials in the photocatalytic decomposition of water. By changing different experimental conditions to prepare a variety of samples and test their properties, we can analyze the optimal parameters for the preparation of this material.

Natural photosynthesis involves a subtle electron transfer mechanism in which freely-moving electron transfer intermediates (plastoquinone and plastocyanin) are capable of effectively separating the photo-generated carriers, and therefore, it has high quantum efficiency. Inspired by this mechanism, in this study, carbonate (CO32-) ions were employed as hole vehicles to promote photo-generated carrier separation, and greatly improved the photocatalytic hydrogen evolution activity of K4Nb6O17 nanosheets. The hydrogen evolution rate at the optimal concentration of CO32- ions reached 2018 μmol h-1 g-1, which was 16.3 times that of the blank sample (124 μmol h-1 g-1). This marked enhancement was based on the transfer of holes from the photocatalyst to the sacrificial reagent (methanol) via CO32- ions; this process is faster than direct hole transfer between the photocatalyst and sacrificial reagent. This bio-inspired strategy provides a facile and cost-effective approach to improve the solar-to-fuel conversion efficiency of photocatalysts.

Tooth enamel is composed of arrayed fluorapatite (FAP) or hydroxyapatite nanorods modified with Mg-rich amorphous layers. Although it is known that Mg2+ plays an important role in the formation of enamel, there is limited research on the regulatory role of Mg2+ in the synthesis of enamel-like materials. Therefore, we focus on the regulatory behavior of Mg2+ in the fabrication of biomimetic mineralized enamel-like structural materials. In the present study, we adopt a bioprocess-inspired room-temperature mineralization technique to synthesize a multilayered array of enamel-like columnar FAP/polymer nanocomposites controlled by Mg2+ (FPN-M). The results reveal that the presence of Mg2+ induced the compaction of the array and the formation of a unique Mg-rich amorphous-reinforced architecture. Therefore, the FPN-M array exhibits excellent mechanical properties. The hardness (2.42 ± 0.01 GPa) and Young's modulus (81.5 ± 0.6 GPa) of the as-prepared FPN-M array are comparable to those of its biological counterparts; furthermore, the enamel-like FPN-M array is translucent. The hardness and Young's modulus of the synthetic array of FAP/polymer nanocomposites without Mg2+ control (FPN) are 0.51 ± 0.04 and 43.5 ± 1.6 GPa, respectively. The present study demonstrates a reliable bioprocess-inspired room-temperature fabrication technique for the development of advanced high-performance composite materials.

Carbon fiber is mainly distributed in the shape of short fibers and continuous fiber bundles as the reinforcing phase in metal matrix composites, and it is seldom studied as braided rope shaped to reinforce the matrix. For this paper, the pretreatment and the surface metallization of the carbon fiber braided rope were studied. Besides, the casting experiments of aluminum-based carbon fiber braided rope composites were performed without external pressure. XPS analysis shows that the surface of the carbon fiber braided rope treated with ultrasonic degumming contains many hydrophilic oxygen-containing functional groups C-OH, C=O, COOH, etc., which can effectively improve the wettability between the carbon fiber braided rope and the aluminum matrix. SEM, EDS, and XRD were used to analyze the micromorphology and structure of the copper plating on the surface of carbon fiber braided ropes obtained from different pH plating solutions. When pH is 12, a continuous, uniform, and dense layer was formed on the surface of carbon fiber braided ropes. In addition, copper coating can effectively inhibit the formation of Al4C3 brittle phase. Finally, the mechanical properties results indicated that the tensile strength of the carbon fiber bundle and carbon fiber rope reinforced composite materials were 69 MPa and 83 MPa, respectively, indicating that the reinforcing effect of the carbon fiber rope is better than that of the carbon fiber bundle.

Biomineralization-associated proteins are responsible for the structure-forming process of biominerals. Aiming to regulate the synthesis of nanostructured TiO2 anatase, an artificial protein 5R5 derived from silaffins was displayed on Escherichia coli surface through genetic manipulation. The genetically modified bacterial cells serve as the framework for the formation of rod-shaped TiO2, assembled by nanoparticles, as well as provide a carbon source in situ during the carbonization process. The particle size and carbon content were controllable by changing the heating temperature and time. The electrode annealed at 800 °C for 1 h shows the highest reversible capacity of 160.2 mA h g−1 after 200 cycles at a current rate of 1C. This unique nanostructured anatase not only shortens the diffusion pathway of lithium ions and electrons, but also improves the electric conductivity and tolerates the volume change during charging/discharging owing to carbon coating. However, the larger particle size and high carbon content were not advantageous to improve lithium storage performance.

Biological materials have excellent mechanical properties due to their organized structures from nano- to macro-scale. Artificial manufacture of materials with anisotropic microstructures still remains challenging. We described a stress-induced method to fabricate anisotropic alginate fibers. Organic-inorganic composite fibers were obtained by incorporating aligned hydroxyapatite (HAP) nanowires into the alginate fiber. Detailed structural characterization revealed the bone-like structure of the HAP-reinforced alginate fibers. Tensile test results showed that the maximum Young's modulus and tensile strength were 4.3 GPa and 153.8 MPa, respectively. A multiscale reinforcing mechanism is proposed after the discussion of the structure-property relationship: highly ordered and compacted nanofibrils aligned along the longitudinal direction at the microscale, and two kinds of alginate gels with different mechanical behaviors at the nanoscale coexisted (acidic alginate gel and calcium-alginate gel). This work validates the effectiveness of the bioinspired fabrication strategy, which inspires further manufacturing and optimization of materials for diverse applications.

Two-dimensional tin sulfides are attracting extensive attention owing to their various potential applications. However, the synthesis methods of tin sulfides are general sophisticated. In addition, the problems of low conductivity and aggregation during charge and discharge severely degrade capacity and long-term cycling stability of lithium ions battery. Herein, we employ bacteria as biotemplate to synthesize homogeneous rod-shaped tin sulfides assembled by interconnected nanosheets. The evolution of structure is revealed elaborately subsequently. The solid rod-shaped structure is firstly formed through adsorbing positively charged Sn4+ on the surface of bacteria. After interacting with S2− source, the SnS2 nanosheets initially appear on the surface, and gradually grow toward interior space to form interconnected structure. Finally, carbon is coated from in situ decomposition of Escherichia coli after calcination in inert atmosphere and thus improves conductivity of material. As lithium ions battery, this anode exhibits a stable cycle capacity of 655 mAh g−1 at 0.5 A g−1 after 200 cycles. This synthesis method is low-cost and provides an ingenious rod-shaped structure which can solve problem of easy agglomeration during charge and discharge. Furthermore, this study may facilitate the development of commercial applications of lithium ions battery.

A bio-inspired layered material of reduced graphene oxide (RGOs) and calcium carbonate was synthesized via a one-pot strategy in DMF/H2O mixed solvent. The experimental results show that the product is a layered material of wrinkled RGOs networks and micron-sized calcium carbonate particles with uniform granular diameter and homogeneous morphology, which are distributed between the layered gallery of the graphene scaffold. The polymorph and the morphology of the in-situ produced calcium carbonate particles can be manipulated by simply changing the temperature scheme. Besides, the graphene oxide was reduced to a certain extent, and the hierarchical wrinkles were generated in the RGOs layer by the in-situ formation of the calcium carbonate particles. This work provides a facile and controllable strategy for synthesizing layered material of RGOs and carbonates, and also presents a platform for making three-dimensional porous wrinkled RGOs networks.

Zirconium carbide (ZrC 0.84 O 0.13 ) nanopowders were consolidated using plasma activated sintering with 0–8 wt% ZrH 2 as the sintering additive to improve the sinterability. Compared with pure ZrC sintering, ZrH 2 additive led to the higher sintering kinetics and lower sintering temperature. This improvement was attributed to the increased carbon-vacancy concentration in the non-stoichiometric ZrC in the presence of ZrH 2 additive during the sintering process. Fully dense and fine-grained ZrC ceramics (1.3 ± 0.2 μm) were achieved at 1650 °C with 6 wt.% ZrH 2 . The final product exhibited the Vicker’s hardness of 21.2 ± 1.0 GPa and fracture toughness of 2.2 ± 0.3 MPa m 1/2 .

In living organisms, confined space with specific chemical composition and elaborate spatial distribution regulates the formation of natural structures. Learning from the natural structure-forming process, novel synthesis approaches in deliberated confined systems have been proposed for obtaining designed structures. Artificial confined systems can effectively regulate the synthesis of materials with defined structures according to the geometry of confinements. Collagen fibrils provide biological confinements for the formation of hierarchical structure with periodic arrangement. Genetically engineered living organisms with designed confinements can direct the synthesis of three-dimensional nanostructures. More novel structures will be rationally fabricated in the future with the aid of deeper understanding of biological processes.

A reduction in the particle size is expected to improve the properties and increase the application potential of high-entropy alloys. Therefore, in this study, a novel sol–gel autocombustion technique was first used to synthesize high-entropy alloys. The average grain size of the prepared nanocrystalline CoCrCuNiAl high-entropy alloys showed was 14 nm with an excellent and uniform dispersion, exhibiting a distinct magnetic behavior similar to the superparamagnetic behavior. We show that the metal nitrates first form (Co,Cu,Mg,Ni,Zn)O high-entropy oxides, and then in situ reduce to CoCrCuNiAl high-entropy alloys by the reducing gases, and the chelation between citric acid and the metal ions and the in situ chemical reactions are the dominant reaction mechanisms. We demonstrate that the sol–gel autocombustion process is an efficient way to synthesize solid solution alloys eluding the restriction of a high mixing entropy.

Learning from the process of biominerals formation provides tremendous ideas for developing advanced synthesis techniques. According to the structure formation of tooth enamel, a recombinant amelogenin his-AmelX was designed and constructed. The protein was over-expressed and could be conveniently purified in one-step heat treatment. The mineralization process of hydroxyapatite was initiated by enzyme AP and regulated by the recombinant amelogenin. Effects of solution pH value and mineralization duration were studied. It was demonstrated that his-AmelX could induce the nucleation of apatite and quicken the growth rate at pH 7.0-7.4, while impeded hydroxyapatite growth at pH 6.8. Moreover, a much denser layer of hydroxyapatite was achieved with the addition of his-AmelX. The present study may not only provide insight into the formation of natural biomaterials but also open a new path to prepare materials under environmentally benign conditions.

A nonvolatile silicon photonic switch constructed by a hybrid integration of a back-gate flash-memory unit with a silicon waveguide is proposed. It can persistently maintain the switching state without continuous supplies due to the memory function of the flash unit, which makes it attractive to reduce the static power consumption. The single-gate control configuration is replaced by dual electrodes (back-gate and drain electrodes) to break the symmetrical electric field and ensure the success of the programming/erasing process. Additionally, a monolayer graphene is utilized instead of polysilicon as the floating gate of flash unit to alleviate the bandwidth-extinction ratio restriction with low insertion loss. Depending on appropriate voltage stimulus, the device either acts as an intensity switch or a phase switch. 26.7μm length is able to achieve 20dB extinction ratio, 1.4dB insertion loss and almost no phase change in a non-resonant configuration, which allows truly broadband performance; while a π-shift is achieved by 30μm length with 31dB/1.65dB extinction ratio/insertion loss incorporating into arms of a Mach-Zehnder interferometer.

TiO2 is a promising anode material for lithium-ion batteries. The electrochemical performance of TiO2 can be improved by optimization of nanostructures. The present study was proposed to control the synthesis of mesoporous nanostructured anatase TiO2 on a genetically modified Escherichia coli surface. A recombinant protein INP-SiliSila containing functional domains of silicatein-α and silaffin was constructed and expressed on the E. coli surface. Deposition of the TiO2 precursor was facilitated by INP-SiliSila on the E. coli surface. Upon calcination, TiO2 coating on the E. coli surface transformed to anatase and formed well-defined rod-shaped particles. The electrochemical performance of the as-prepared anatase TiO2 as anode electrodes was improved and better than that of most reported ones. The present study not only provides an organism-based approach for fabricating nanostructured anatase TiO2 with enhanced electrochemical performance, but also opens a new avenue to take advantage of genetically modified bacterial surfaces in the synthesis and structure control of materials.

A genetically modified bacterial surface not only serves as a confined environment for controlling the monodispersity of particle size, but also provides a carbon source in situ. The carbon coated SnO2 composite exhibits good lithium storage properties as an anode electrode, which are due to the ultrasmall size of the particles, the carbon coating and mesoporous structure.

Confinement is common in biological systems and plays a critical role in the structure-forming process of biominerals. However, the knowledge of confinement effects on biomineralization is limited due to the lack of specific chemical structures and elaborate spatial distribution. In this article, we explore the confined mineralization of amorphous calcium carbonate (ACC) within collagen fibrils. Three issues of the confined mineralization of ACC within collagen fibrils were investigated, including the morphology and characteristics of the confined mineralization of ACC within collagen fibrils; the initiation and development of the confined mineralization of ACC within collagen fibrils; and the driving mechanism of ACC infiltration into collagen fibrils. Results show that the negatively charged ACC droplets were attracted to positively charged gap regions of collagen fibrils through electrostatic interactions, infiltrated into collagen fibrils, and then transformed into the crystalline phase. The observation of juxtaposed crystalline and amorphous phases on the surface of fibrils indicates that a secondary nucleation mechanism may be responsible for the co-orientation of calcite nanocrystals. Through modifying the wettability of amorphous calcium carbonate with magnesium ions, it is verified that the infiltration of ACC into collagen fibrils was driven by capillary forces. The present study not only provides evidence of the confinement effects in biomineralization but also facilitates the understanding of the in vivo bone formation process. It may also open up a new avenue in the bioprocess-inspired synthesis of advanced materials.

Surface composition control plays a crucial role in electrocatalytic reactions for Pt-based bimetallic materials. However, strategies for controlling their surface composition always require extreme conditions including the use of harsh agents, the need for high temperatures, and the necessity of complex procedures. Here we develop a photo-assisted method to fabricate Au@PtAu core-shell nanoparticles (NPs) with well-tuned surface composition at ambient temperatures. It was found that their surface composition can be continuously regulated by the addition amount of HAuCl4 under photo-irradiation. By incorporating Au atoms, the synthesized Au@PtAu NPs show significantly improved properties for methanol electro-oxidation, owing to the reduced CO formation and the weakened binding strength of CO on Pt. The catalytic activity and durability vary with the relative active surface area of Pt or Au (PtSurf. or AuSurf.), and the optimal PtSurf. was found to be ∼64% (AuSurf. ∼36%). The present work highlights the “photo-assisted method” as a green and effective method to synthesize advanced materials with optimized functional properties.

Extreme conditions such as high temperature and/or pressure are usually required for the transformation of amorphous silica to crystalline polymorphs. In this article, we present our results that amorphous silica can be deposited on a bacterial surface and transformed to cristobalite at a relatively low temperature and ambient pressure. The phase transformation of amorphous silica to cristobalite under thermal treatment was investigated by a variety of methods including X-ray diffraction, electron microscopy, and Fourier transform infrared spectroscopy. Results show that amorphous silica on a bacterial cell surface exhibits a direct phase transformation to cristobalite structure at a relatively low temperature (800°C). The surface charge of the bacterial cells does not affect the phase transformation. Three Gram-negative bacteria and three Gram-positive bacteria have been tested in the present study. All these bacteria have been found to facilitate the phase transition of amorphous silica into cristobalite. The observation of amorphous silica transformation on bacterial surfaces to cristobalite highlights the use of bacteria in the synthesis and structure control of silica minerals.

Highly oriented calcium carbonate lamellas are exquisite structure produced by biomineralization. Strategies mimicking nature have been developed to synthesize inorganic materials with excellent structures and optimal properties. In our strategy, egg white protein and zinc ion were employed in the solution to induce the crystallization of calcium carbonate, resulting in the macroscopic aragonite laminate with an average length of 1.5 mm, which was comprised of single-crystalline tablets. During the crystallization at initial stage, it was found that the particles displayed the characteristics of amorphous calcium carbonate, which was then transformed into the sophisticated structured aragonite through a multistage assembly process. The rebuilt nacre structure in vitro was achieved owing to the synergistic effects of egg white protein and zinc ion.

Taking lessons from the structure-forming process of biominerals in animals and plants, one can find tremendous inspirations and ideas for developing advanced synthesis techniques, which is called bio-process inspired synthesis. Bone, as a typical representative of biominerals, is constituted of mineralized collagen fibrils, which are formed under the functions of non-collagenous proteins (NCPs). Intrafibrillar mineralization is the consequence of a synergy among several NCPs. In the present study, we have designed a multi-functional protein, named (MBP)-BSP-HAP, based on bone sialoprotein (BSP) and hydroxyapatite binding protein (HAP), to mimic the intrafibrillar mineralization process in vitro. The three functional domains of (MBP)-BSP-HAP provide the artificial protein with multiple designated functions for intrafibrillar mineralization including binding calcium ions, binding collagen, and binding hydroxyapatite. Platelet-like hydroxyapatite crystals periodically arranged inside the collagen fibrils have been achieved under the function of (MBP)-BSP-HAP. The mechanism of intrafibrillar mineralization directed by the multi-functional protein was proposed. This work may not only shed light on bio-process inspired approaches for more economic and efficient biomimetic synthesis, but also be helpful in understanding the natural process of bone formation for bone regeneration and tissue repair.

Inspired by the structure-forming process of biominerals, scientists have been successful in synthesizing materials with elegant structures by using organic matrices as templates. However, there are still issues relating to the exquisiteness and complexity of natural organic matrices in living organisms which have kept their activities out of chemists' control, in particular the functional properties of such materials. Here we employ natural assorted proteins, which are derived from the extrapallial fluid in living mussels, to synthesize hierarchically porous nitrogen-doped TiO2 in a single process. The silk-like organic residues in the powders clearly show that the proteins act to segment the space for TiO2 nucleation. We also demonstrate phase control over the material, with the ability to synthesize pure anatase. The synthesized TiO2 materials show a significant improvement in visible-light photocatalytic activity for both the degradation of organic pollutants and hydrogen production. The degradation of RhB could be almost completed in just 20 min. The visible-light photocatalytic activities vary with the concentrations of EPF proteins, and the optimal concentration of protein was found to be 600 μg mL-1. The present work highlights its potential application as a natural organic matrix in producing advanced materials with optimized functional properties.

Strategies that attempt to mimic the well-defined structures or unique functions of natural biological materials have succeeded in designing and synthesizing bio-inspired materials in the past twenty years. Furthermore, natural structure-forming processes in biological systems can efficiently and accurately fabricate biomaterials under environmentally benign conditions, in contrast to our anthropogenic technologies wherein harsh conditions are commonly prerequisites. Hence, natural structure-forming processes are well worth studying in pursuit of new techniques for fabricating advanced materials with novel structures and functions, a new research direction, called “bioprocess-inspired fabrication” has been proposed in recent years. In this review, we systematically introduce and evaluate the advance of bioprocess-inspired fabrication of materials for the first time. We describe advances in the exploration and development of bioprocess-inspired fabrication technology and related exquisite materials. We summarize in detail the advances in biomineralization, photosynthesis and other bioprocess-inspired fabrication methods, and have finally discussed some new ideas and directions that need to be emphasized in the future. Bioprocess-inspired fabrication of materials will convey far-reaching implications for materials science, life science, biology, chemistry and other related interdisciplinary fields.

Genetically engineered living organisms direct the synthesis of nanostructured anatase with nanoparticle, mesoporous structure and carbon coating characteristics which shows excellent lithium storage performance., Biomineral formation processes in nature are temporally and spatially regulated under the functions of biomolecules in a confined space. It is potentially very productive to rationally design a mineralized system by taking into account confined space as well as biomolecules. The laboratory technique of “bacterial cell surface display” is an ideal platform to host catalytically active proteins in a three-dimensionally confined space. In the present study, aiming to regulate the synthesis of nanostructured TiO2 anatase, repeating segments of silaffin were displayed on Escherichia coli surfaces through genetic manipulation. The displayed protein electrostatically interacted with a titanium source and catalyzed the hydrolysis of titanium dioxide precursors through hydrogen bonding interactions on the cell surface. In the subsequent calcination process, the genetically modified cells not only served as a framework for producing rod-shaped TiO2 assembled by nanoparticles, but also provided a carbon source in situ. The size of nanoparticles was controlled by changing the number of tandem repeats of the protein segment. The as prepared TiO2 anatase exhibited unique characteristics including nanosized anatase crystals, mesoporous structure and carbon coating. When tested as the anode electrode of a lithium-ion battery, it showed excellent lithium storage performance. The carbon coated anatase anode shows a higher specific capacity of 207 mA h g–1 after 200 cycles at a current rate of 1C and an ultra-long cycling lifetime of 5000 cycles with an outstanding retention capacity of 149 mA h g–1 at a higher rate of 10C. This bioprocess-inspired approach may help broaden the scope and impact of nanosized biominerals.

Organic thin-film transistors (OTFTs) with high transmittance and low photosensitivity have been demonstrated. By using titanium dioxide nanoparticles as the additives in the polymer gate insulators, the level of device photoresponse has been reduced. The device shows simultaneously a high transparence and a minimal threshold voltage shift under white light illumination. It is inferred that the localized energy levels deep in the energy gap of pentacene behave as the recombination centers, enhancing substantially the recombination process in the conducting channel of the OTFTs. Therefore, the electron trapping is relieved and the shift of threshold voltage is reduced upon illumination.

A novel optoelectrofulidic system integrated optical image concentration and alignment system, dielectrophoresis phenomenon, microfluidic and friendly real-time control interface is first reported in this article. A new application of photoconductive material oxotitanium phthalocyanine (TiOPc) for microparticle applying has been first described and demonstrated by our research group. Basis on the special character of the photoconductive material, a TiOPc-based optoelectronic tweezers (Ti-OET) is utilized for single and massive cells/particles manipulation. The objects wanted to be manipulated are defined with different behaviors (e.g., press, release, drag and move) using Flash® software when the cursor acts on them. It also reveals the application for biological application to form the cells trapping with three sorts of cells, HMEC-1, HepG2 and HEK293t. Another application of our optoelectrofulidic system is to fabricate a TiOPc-based flow cytometry chip which can be used for sorting the 15μm diameter particles with 105 μm/s velocity. When the 10Vp.p. voltage and 45 kHz AC frequency apply on the top and button ITO electrode, the illuminated light pattern will become a spatially virtual switch inside the microchannel. The dielectrophoresis force between top ITO glass and button photoconductive layer controlled by the friendly interface will concentrate the cells/particles as a straight line and individually direct each one in different paths. In summary, we have established an optoelectronfulidic-based chip and spatially virtual switch system which are applied for cell pattern and particles sorting. In the future, this easy manipulation approach can place the full power of optoelectronfulidic chip into the biological operators' hands.

In optical tweezers, it can be comprehended that the larger the inclination angle between the condensed laser beam and the optical axis contributes more to axial trapping force, while the central part of laser beam with smaller inclination angle contributes more transverse trapping force. Therefore donut-shaped beam is used to improve the problem of lessaxial trapping for common optical tweezers. Some research reports have shown that the efficiency of a trapping force can be enhanced by using a donut-shaped beam. In this paper we present the dependence of the axial and the transverse components of a trapping force on the configuration of a focused donut-shaped beam. The simulation result will provide a simple and easy guide for optical tweezers users to adjust the configuration of a focused donut-shaped beam for optimal trapping performance.

This paper reports our updating development for the organic photoconductive dielectrophoresis (OPDEP) by using titanium oxide phthalocyanine (TiOPc) material for the manipulation of micro-objects. The advantages of organic photoconductive material include non-toxicity, low cost, easy coating fabrication, flexibility, panchromaticity and high photosensitivity [1]. TiOPc has the high photoconductivity and the optical absorptions in the near infrared region (550 – 850 nm) to be a candidate of the light-sensitive charge generation layer. OPDEP chip is easily mass-produced by using a spin-coating process. Here, we demonstrate two kinds of the manipulations of micro-particles on our OPDEP chip. Firstly, the trapping and movement of single micro-particle is achieved by the ring shaped virtual electrode. Secondly, the steel rim shaped virtual electrode is designed to rotate micro-particles and characterize the OPDEP induced force.

Summary form only given. The requirements for satellite station-keeping include low levels of thrust applied intermittently over the lifetime of the satellite and high specific impulse to optimize payload efficiency and high reliability. Advances in microelectromechanical systems (MEMS) technology have enabled the design and fabrication of microthrusters that can meet these requirements. The first step is to model and simulate a microthruster, with the eventual goal of building and testing arrays of thrusters. This research presents the modeling and simulation of a MEMS-based microthruster that generates a pseudospark discharge in a hollow cathode configuration. The ion microthruster operation uses a 5-nanosecond (ns) pulse of 500 V in argon gas at 10 torr. Simulation runs are executed using XOOPIC PIC-MCC code (developed by the Plasma Theory & Simulation Group of UC-Berkeley) for a microthruster with accelerator/extractor stages. Simulation results have been obtained for the microscale thrusters with one- and three-extractor stages. The average kinetic energy and number of particles (for both argon ions and electrons) have been plotted over the 5-ns pulse. The microthruster potential profiles and particle number densities have been recorded at times t = 2 ns and t = 5 ns. Estimates of the thrust and specific impulse have been determined from the flux and angular distribution data of the exiting ions

The research work reported in this paper focuses on developing an electrochemical micropump and a DNA mixing and analysis system using the electrochemical pumps for actuation. The micropum consists of two swing-door check valves and an electrochemical pumping chamber. In the prototype system, two micropumps were used to deliver the reagents and DNA samples respectively. The SU-8 based UV-lithography process was used to fabricate the system on a glass substrate.

A high quality low temperature oxide technology (LTO) was introduced as the emitter/base junction isolation layer of a Silicon-Germanium. (SiGe) HBT. Due to its lower Ge strain relaxation and boron out-diffusion effect, we showed that devices were obtained with a significant improvement in reliability, DC and RF performance in comparison with those fabricated using conventional LTO or thermal oxidation methods.

Microbubbles have a variety of applications in science and biological technology. Here, we demonstrate the manipulation of the picoliter gas bubble (picobubble) based on the optoelectronic-mechanism. The organic photoconductive material, titanium oxide phthalocyanine (TiOPc), was developed to make the light-sensitive substrate of this optoelectronic chip. The virtual electrodes are formed by projecting the dynamic light pattern onto TiOPc layer for generating the desired nonuniform electric field. The picobubble suspended in silicone oil can be manipulated with the velocity of 40–50 μm/s. The driving force up to 160 pico-Newtons could be generated for manipulating a gas bubble of 300 picoliters.

We develop light-driven optoelectronic tweezers based on the organic photoconductive material titanium oxide phthalocyanine. These tweezers function based on negative dielectrophoresis (nDEP). The dynamic manipulation of a single microparticle and cell patterning are demonstrated by using this light-driven optoelectronic DEP chip. The adaptive light patterns that drive the optoelectronic DEP onchip are designed by using Flash software to approach appropriate dynamic manipulation. This is also the first reported demonstration, to the best of our knowledge, for successfully patterning such delicate cells from human hepatocellular liver carcinoma cell line HepG2 by using any optoelectronic tweezers.