Solution Deposition Research Articles

Tailoring of morphology and microstructure dependent optical properties of solution processed Ge23Sb7S70 chalcogenide glass films

This paper presents an extensive study carried out to understand the process of tailoring the morphology of solution processed nanostructured Ge23Sb7S70 Chalcogenide glass thin films and to analyze their microstructure dependent optical properties. To tailor the desired morphology of the solution processed ChG films different synthesis parameters have been optimized, step by step. It has been observed that the dissolution time and concentration of Chalcogenide glass precursor solution used for the deposition of solution processed films have the major role in determining their morphology. Annealing of solution processed chalcogenide glass film is an important step to get rid of residual solvent from the film. This study reveals that annealing may disturb the morphological uniformity of solution processed chalcogenide glass films and a careful optimization of annealing step is required to maintain the morphological uniformity. Microstructure dependent optical properties such as refractive index and optical bandgap of solution processed chalcogenide glass films have also been analyzed in this study. It has been observed the size of the microstructures insolution processed chalcogenide glass films greatly influences the optical properties of these films.

Optimization of sodium alginate aided bio-deposition treatment of recycled aggregates and its application in concrete

Bio-deposition treatment based on microbial induced carbonate precipitation is a promising method to enhance the properties of recycled aggregates, because the generated biological precipitates can repair the defects of recycled aggregates. However, the main problem of current bio-deposition treatment is the uneven distribution of the precipitates on aggregates, which greatly diminishes the enhancing efficiency. Therefore, sodium alginate (SA) was innovatively utilized to improve the uniformity of the precipitates on aggregates surface during the bio-deposition treatment in this study. The principle was that SA and the network structure of Ca-alginate were applied to uniformly “fix” the bacteria on the surface of recycled aggregates, which was supposed to promote the uniform in-situ precipitation on the surface of aggregates. The influences of the concentrations of bacteria and deposition solution (containing equimolar urea and Ca-nitrate), on the treatment efficiency were studied. The results indicated that the optimized SA-aided bio-deposition treatment group was under 0.2 wt% SA, 109 CFU/mL of bacterial solution, and 0.5 M of deposition solution, the water absorption of aggregates was reduced by 39.63% on average, the effective mass increase of calcium carbonate was increased by 3.14%, and the crush value decreased by about 13.8%. Using aggregates subjected to the optimized SA-aided bio-deposition treatment to produce concrete, it was found that, comparing with the untreated recycled aggregate concrete, the saturated water absorption of the treated recycled aggregate concrete decreased by about 15.3%. It can be concluded that the optimized SA-aided bio-deposition treatment can improve the strength of aggregates and durability of recycled concrete.

Disentangling the responses of dissolved organic carbon and nitrogen concentrations to overlapping drivers in a northeastern United States forested watershed

The concurrent reduction in acid deposition and increase in precipitation impact stream solute dynamics in complex ways that make predictions of future water quality difficult. To understand how changes in acid deposition and precipitation have influenced dissolved organic carbon (DOC) and nitrogen (N) loading to streams, we investigated trends from 1991 to 2018 in stream concentrations (DOC, ~3,800 measurements), dissolved organic nitrogen (DON, ~1,160 measurements), and dissolved inorganic N (DIN, ~2,130 measurements) in a forested watershed in Vermont, USA. Our analysis included concentration-discharge (C-Q) relationships and Seasonal Mann-Kendall tests on long-term, flow-adjusted concentrations. To understand whether hydrologic flushing and changes in acid deposition influenced long-term patterns by liberating DOC and dissolved N from watershed soils, we measured their concentrations in the leachate of 108 topsoil cores of 5 cm diameter that we flushed with solutions simulating high and low acid deposition during four different seasons. Our results indicate that DOC and DON often co-varied in both the long-term stream dataset and the soil core experiment. Additionally, leachate from winter soil cores produced especially high concentrations of all three solutes. This seasonal signal was consistent with C-Q relation showing that organic materials (e.g., DOC and DON), which accumulate during winter, are flushed into streams during spring snowmelt. Acid deposition had opposite effects on DOC and DON compared to DIN in the soil core experiment. Low acid deposition solutions, which mimic present day precipitation, produced the highest DOC and DON leachate concentrations. Conversely, high acid deposition solutions generally produced the highest DIN leachate concentrations. These results are consistent with the increasing trend in stream DOC concentrations and generally decreasing trend in stream DIN we observed in the long-term data. These results suggest that the impact of acid deposition on the liberation of soil carbon (C) and N differed for DOC and DON vs. DIN, and these impacts were reflected in long-term stream chemistry patterns. As watersheds continue to recover from acid deposition, stream C:N ratios will likely continue to increase, with important consequences for stream metabolism and biogeochemical processes.

Large area small-molecule thin films deposited by the doctor blade technique implemented with computer numerical control machine

A systematic study of parameters allowing small-molecule thin film deposition over a large area by the doctor blade technique is reported. The solution concentration, deposition temperature, and speed coverage of the deposition technique were evaluated to determine these parameters' importance on the thickness and homogeneity of the film. The solution concentration was 5, 7.5, and 10 mg/ml; temperatures from 75 to 100 °C and speed coverage of 250, 500, and 750 mm/min were evaluated. The best conditions to achieve homogeneous and smooth films were a concentration of 10 mg/ml, a preheating temperature of 100 °C, and a speed coverage of 500 mm/min. The average thickness for small-molecule films is about 80–86 nm, and roughness is as low as 1.7 nm. The values were comparable to those measured in films deposited by the spin coating technique. It should be worth noting that film deposition was conducted with a lab-design and fabricated computer numerical control machine. The deposited films were used as an active layer in light-emitting devices with an active area of 1.25 cm2. Therefore, it is possible to achieve a homogeneous small-molecule film by varying the parameters of both the solution and the deposition technique.

Influence of the Addition of Rare Earth Elements on the Energy Storage and Optical Properties of Bi0.5Na0.5TiO3–0.06BaTiO3 Polycrystalline Thin Films

Rare earth element-doped Bi0.5Na0.5TiO3-BaTiO3 (BNT-BT-RE) polycrystalline thin films were processed on a platinized substrate by chemical solution deposition. The microstructure, dielectric, and ferroelectric properties were investigated for all prepared films. It was found that the incorporation of rare earth elements into the BNT-BT matrix increases both the dielectric constant and the breakdown strength while maintaining low dielectric losses, leading to an enhancement of the energy storage density to Wrec = 12 and 16 J/cm3 under an effective field of E = 2500 kV/cm, for Nd- and Dy-based films, respectively. The optical properties of films containing the lanthanide element were investigated and the obtained results bear interest for luminescence applications. The simultaneous appearance of ferroelectric and optical properties in the system under investigation is very promising for advanced optoelectronic devices.

Ferroelectric-gated variable-area capacitors with large capacitance tuning ratio using Ce-doped HfO2 film for both gate insulator and capacitor layer

We demonstrate a three-terminal variable-area capacitor integrated with a ferroelectric-gate field-effect transistor (FeFET) and a ferroelectric capacitor. A FeFET using an indium tin oxide (ITO) channel and a ferroelectric Hf0.86Ce0.14O2 gate insulator was fabricated by chemical solution deposition. The fabricated FeFET exhibited a high on-current of ∼0.18 mA μm−1 and a large on-/off-current ratio of 106. The large charge controllability of the FeFET allows the conductive ITO channel to act as an electrode switch that connects and disconnects two capacitors. In order to increase the capacitance density and the capacitance tuning ratio (CTR), we propose a structure wherein a 25-nm-thick ferroelectric film is applied as both a gate insulator and a capacitor. The proposed structure exhibited a large capacitance density of 12.5 nF mm−2 and a wide CTR of approximately 10 000. This work facilitates future integration of passive and active components for advanced highly efficient and miniaturized electronics.

Printing Formation of Flexible (001)-Oriented PZT Films on Plastic Substrates.

High-quality, uniaxially oriented, and flexible PbZr0.52Ti0.48O3 (PZT) films were fabricated on flexible RbLaNb2O7/BaTiO3 (RLNO/BTO)-coated polyimide (PI) substrates. All layers were fabricated by a photo-assisted chemical solution deposition (PCSD) process using KrF laser irradiation for photocrystallization of the printed precursors. The Dion-Jacobson perovskite RLNO thin films on flexible PI sheets were employed as seed layers for the uniaxially oriented growth of PZT films. To obtain the uniaxially oriented RLNO seed layer, a BTO nanoparticle-dispersion interlayer was fabricated to avoid PI substrate surface damage under excess photothermal heating, and the RLNO has been orientedly grown only at around 40 mJ·cm-2 at 300 °C. The prepared RLNO seed layer on the BTO/PI substrate showed very high (010)-oriented growth with a very high Lotgering factor (F(010) = 1.0). By using the flexible (010)-oriented RLNO film on BTO/PI, PZT film crystal growth was possible via KrF laser irradiation of a sol-gel-derived precursor film at 50 mJ·cm-2 at 300 °C. The obtained PZT film showed highly (001)-oriented growth on the flexible plastic substrates with F(001) = 0.92 without any micro-cracks. The RLNO was only uniaxial-oriented grown at the top part of the RLNO amorphous precursor layer. The oriented grown and amorphous phases of RLNO would have two important roles for this multilayered film formation: (1) triggering orientation growth of the PZT film at the top and (2) the stress relaxation of the underneath BTO layer to suppress the micro-crack formation. This is the first time that PZT films have been crystallized directly on flexible substrates. The combined processes of photocrystallization and chemical solution deposition are a cost-effective and highly on-demand process for the fabrication of flexible devices.

Electrical conductivity and corrosion resistance of Mo/Ti/Mn-based composite conversion films on AZ91D magnesium alloy

In this reported study, conductive composite conversion films on an AZ91D magnesium alloy were prepared by adding Ga3+ to a deposition solution that contained molybdenum, titanium and manganese ions. The Ga3+ significantly improved the conductivity and corrosion resistance of the resulting films. The electrical contact resistance (ECR) of the Molybdenum/Titanium/Manganese (MTM) film decreased from 0.436 Ω/in2 to 0.106 Ω/in2 at 200 psi when Ga3+ was added to form the Molybdenum-Titanium-Manganese-Gallium (MTMG) film. In addition, the polarization resistance of the Ga3+ amended film increased from 633.1 Ω·cm2 to 1930.835 Ω·cm2, MTMG showed obvious passivation behavior. The Ga3+ doping appeared to increase the carrier concentration and narrow the band gap of the semiconductor film. The N-type semiconductor carrier concentration increased from 2.11 × 1019 cm−3 to 7.052 × 1019 cm−3 in the MTMG film vs the MTM film. The P-type semiconductor carrier concentration in the MTMG film increased from 2.727 × 1018 cm−3 to 3.480 × 1019 cm−3 compared to the MTM film. The MTM band gap decreased from 2.916 eV to 2.714 eV in the MTMG film, which was attributed to the cross-doping of Ga3+ with transition metals in the MTMG material. The MTMG film had a three-layer structure, which preferentially formed a thin film on the β-phase and subsequently grew layer by layer.

Cone Angle Modulation of Silicon Nanocones through Double Etching Processes in Metal-Assisted Chemical Etching

All-wet metal-assisted chemical etching (MACE) has been demonstrated as a simple and effective method to fabricate silicon nanocones (SiNCs). The properties of SiNCs strongly depend on their structure parameters such as the cone angle and can be optimized through modulating the cone angle. However, cone angle modulation of SiNCs in all-wet MACE processes has not been achieved. Here, we report the fabrication of SiNCs with different cone angles through double etching processes in all-wet MACE. Large-size silver nanoparticles (AgNPs) were first obtained by solution deposition. After a common etching process, a double etching process with diluted etching solutions was introduced. In the etching step, AgNPs gradually reduced with the Si etching, which resulted in the formation of SiNCs. The cone angles of SiNCs depend on the changing rate of AgNP sizes. Based on this mechanism, SiNCs with different cone angles from 5°-20° were successfully fabricated by changing the concentration of the diluted etching solution in the double etching process. The contact angle of SiNCs with different cone angles was also investigated. It is found that the wettability of the SiNCs becomes poorer with increasing cone angles. Cone angle modulation of SiNCs in all-wet MACE will benefit the property control and the wide applications of SiNCs.

Influence of the intermediate oxidation layer on the characteristics of lead zirconate titanate thin films with aluminium substrate

This paper presents a flexible piezoelectric device that has been realized by depositing lead zirconate titanate (PZT) thin films by chemical solution deposition (CSD) on a commercial aluminum foil as a substrate. The thermal treatment required for the crystallization of the PZT thin films leads to the oxidation of the substrate and a parasitic intermediate layer of alumina (Al2O3) is formed between the substrate and the first PZT layer. The comparison with and without the use of a conductive ruthenium dioxide (RuO2) interlayer, which can shunt the insulating alumina layer, showed the influence of the latter on the different characteristics of the material. The thickness of the alumina layer on the surface of the aluminum substrate after deposition of the PZT film (≈ 39 nm) was determined by calculation and confirmed by transmission electron microscopy (TEM). Dielectric characterization of the sample without considering this layer gives the permittivity of the Al2O3/PZT bilayer and not the active material alone (PZT). A relative permittivity value of 313 is measured against 558 for the single PZT layer if the alumina layer is taken into account, which means a decrease of 44%. The piezoelectric characterization is also influenced by the alumina layer, the piezoelectric coefficient is 14 pC/N while it is 26 pC/N when this layer is taken into account. This study evidences and quantitatively evaluates the influence of the oxidation layer (Al2O3) on the dielectric and piezoelectric characteristics and mechanical energy harvesting performances.

Benzimidazole-modified polyaniline micro-shells for electrochemical detection of cadmium in aqueous solution

Benzimidazole-functionalized polyaniline (BMPANI) was synthesized by interfacial poly­merization technique and used for electrochemical sensing of cadmium ions in an aqueous solution. The material was characterized for its structural and morphological features using Fourier-transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM). The BMPANI has a micro-shell structure produced from the self-assembly of the monomer units in solution before the polymerization reaction. The material was trialed for cadmium ion sensing using a BMPANI-modified carbon paste electrode (BMPANI-CPE). Electrochemical techniques, i.e., cyclic voltammetry (CV) and differential pulse anodic stripping voltammetry (DPASV), were performed to assess the sensing characteristics of the material. Various electrode preparation parameters, i.e., deposition potential, pH of deposition solution, and thickness of the active layer, were optimized to achieve the highest level of sensitivity. The selectivity towards cadmium ions, interference from other ions, as well as stability and reusability of the BMPANI-CPE, were also examined and found to be satisfactory.

Magnetic field control and swift heavy ion beam assisted tuning of resistive switching properties of BSFO/CFO/LNO heterostructures

Resistive switching (RS) behavior in mixed oxide insulators has shown a great promise as memristors or non-volatile resistive random-access memory (RRAM) applications. For dilute magnetic oxide multilayers, a novel approach of controlled defects induced and the magnetic field control of RS behavior is proposed. Resistive switching in Bi0.6Sr0.4FeO3 /CoFe2O4 /LaNiO3 (BSFO/CFO/LNO) multilayer heterostructures has been investigated as a case study. All oxide junctions consisting of conducting LaNiO3 (LNO) bottom electrode and BSFO-CFO active layers were fabricated by using chemical solution deposition. A set of samples were irradiated with 150 MeV Ag11+ ions for three different ion fluence of ∼1 × 10+11 ions cm−2, 1 × 10+12 ions cm−2 and 5 × 10+12 ions cm−2. Polycrystalline phase pure films with smooth, crack free surfaces were observed for pristine and irradiated samples. Optical spectroscopy revealed a decrease in the transmittance upon increasing ion fluence due to increase in the light scattering centres. The optical band gap showed a systematic decrease from 2.09 eV to 1.65 eV with increasing ion fluence. Room temperature I-V characteristics showed consistent and pronounced bipolar switching for all samples below ± 5 V. Upon applied magnetic fields of 0.58 T, the resistive switching ratios were found to increase significantly and were further tuned by 150 MeV Ag11+ ion beam irradiations. The magnetic field control of electrical transport properties in the controlled defect assisted oxide heterojunctions offers new insights to the existing understanding of oxide-based RS mechanism.

Effect of membrane deposition methods on the performance of membrane electrode assemblies

AbstractThe performance of proton exchange membrane fuel cells (PEMFCs) is closely related to the preparation process of the membrane electrode assemblies (MEAs). The direct membrane deposition approach can achieve excellent interfacial connection between functional layer, as well as simplifying the MEA manufacturing process. Nevertheless, it has been recognized that for this approach, the permeation of the electrolyte solution into the catalyst layer is a challenge, and it is associated with the deposition method. In this study, three MEAs are prepared by spraying, blade coating, and a combination of the two. The effect of the electrolyte solution deposition methods on the properties of the MEAs is analyzed. The MEA prepared using the combination of spraying and blade coating delivers the highest performance of up to 0.618 W cm−2 (80°C with H2/air conditions at normal pressure). In this method, the spraying layer can alleviate the negative effect of cracks on the gas diffusion electrode surface, and the blade‐coating layer can improve the membrane uniformity. The MEA prepared by this method exhibits excellent cell performance compared to the traditional catalyst coated membrane type MEA, particularly in low‐humidity conditions. This work provides guidance for the preparation of high‐performance MEAs for PEMFCs.

Control of Columnar Grain Microstructure in CSD LaNiO3 Films.

Conductive LaNiO3 (LNO) films with an ABO3 perovskite structure deposited on silicon wafers are a promising material for various electronics applications. The creation of a well-defined columnar grain structure in CSD (Chemical Solution Deposition) LNO films is challenging to achieve on an amorphous substrate. Here, we report the formation of columnar grain structure in LNO films deposited on the Si-SiO2 substrate via layer-by-layer deposition with the control of soft-baking temperature and high temperature annealing time of each deposited layer. The columnar structure is controlled not by typical heterogeneous nucleation on the film/substrate interface, but by the crystallites' coalescence during the successive layers' deposition and annealing. The columnar structure of LNO film provides the low resistivity value ρ~700 µOhm·cm and is well suited to lead zirconate-titanate (PZT) film growth with perfect crystalline structure and ferroelectric performance. These results extend the understanding of columnar grain growth via CSD techniques and may enable the development of new materials and devices for distinct applications.

Vapor-Deposited n = 2 Ruddlesden–Popper Interface Layers Aid Charge Carrier Extraction in Perovskite Solar Cells

Interfacial passivation with bulky organic cations such as phenetylammonium iodide has enabled high performance for metal halide perovskite optoelectronic devices. However, the homogeneity of these interfaces and their formation dynamics are poorly understood. We study how Ruddlesden–Popper 2D phases form at a 3D perovskite interface when the 2D precursors are introduced via solution or via vapor. When using vapor deposition, we observe uniform coverage of the capping layer and the formation of a predominantly n = 2 Ruddlesden–Popper phase. In contrast, when using solution deposition, we observe the presence of a mixture of n = 2 and n = 1 in the film and the formation of aggregates of the organic cations. As a result of the better phase purity and uniformity, vapor deposition enables higher median solar cell performance with narrower distribution compared to solution-treated films. This study provides fundamental information that the perovskite community can use to better design capping layers to achieve higher charge extraction efficiencies.

Solvent Effect on Small-Molecule Thin Film Formation Deposited Using the Doctor Blade Technique

Small molecule thin films are the core of some organic optoelectronic devices. Their deposition by solution processes is an advantage for device fabrication and can be achieved via spin coating for small areas and slot-die or doctor blade for larger areas. Solution deposition of small molecule thin films is usually processed only with medium polarity solvents. Herein, the use and influence of solvents with several polarities and physicochemical properties to form small-molecule homogeneous thin films via the doctor blade technique over an area of 25 cm2 have been explored. Solvents with different polarity, heptane, chlorobenzene, N,N-dimethylformamide, acetonitrile, and methanol were used along with different deposition temperatures, from room temperature up to near the boiling temperature for each solvent. With heptane and chlorobenzene, smooth films with an average roughness of 3 nm and thickness of 100–120 nm were obtained. The film was homogeneous over the whole substrate for temperatures from room temperature to close to the boiling temperature of both solvents. On the other hand, with dimethylformamide, a film is observed when the deposition is conducted only at room temperature; when the deposition temperature increases, the formation of agglomerates of several sizes from 1 to 5 nm was observed. With acetonitrile, and methanol, no films were formed, and only nanoaggregates were created on the substrate due to the solvent high vapor pressure, and the agglomerate size depends on the deposition temperature. The measure of the contact angle of pure solvent and solutions indicated that wettability helps to film formation over the whole substrate. For heptane and chlorobenzene, a small angle was measured; meanwhile, the contact angle is large in acetonitrile leading to the formation of nanoaggregates. In the case of methanol solution, although it wets very well, no film is deposited because it has high volatility.

Investigation of resistive switching properties in acceptor-induced Sr(Fe,Ti)O3 thin film memristor

In this work, the amorphous SrFe0.1Ti0.9O3-δ (a-SFT10) thin film was prepared on FTO/Glass substrate by chemical solution deposition process and then annealed at 500 ℃. Step Profiler measurements and SEM images revealed that the thickness of the a-SFT10 film was around 300 nm. The a-SFT10 thin film was found to have a smooth surface but was not crystalline. X-ray photoelectron spectroscopy (XPS) was used to analyze the chemical states of the film. Fe2+ and Fe3+ coexist in a-SFT10, according to XPS results, with Fe3+ being the dominating state. The mixed valence state of iron ions may be related to oxygen vacancies. Current-voltage characteristics were conducted to study the electrical properties. The uniform switching voltages, high switch ratio and good endurance were obtained. The ratio of high and low resistance (RH/RL) is up to 103 under positive bias voltage. The physical mechanisms underlying resistance switching behaviors were also investigated. The results show that the Ohmic, space charge limited current and Schottky conduction mechanisms dominated in different voltage ranges of A-SFT10 films, respectively. The oxygen vacancies associated with the acceptor doping play a significant role in the current characteristic in Au/a-SFT10/FTO/Glass device. Our findings suggest that the device has potential applications in future resistive random access memory.

Investigation of Electrochemical Assisted Deposition of Sol-Gel Silica Films for Long-Lasting Superhydrophobicity

Current methods for the protection of metal surfaces utilize harsh chemical processes, such as organic paint or electro-plating, which are not environment-friendly and require extensive waste treatments. In this study, a two-step approach consisting of electrochemical assisted deposition (EAD) of an aqueous silane solution and a dip coating of a low surface energy silane for obtaining a superhydrophobic self-cleaning surface for the enhanced protection of copper substrate is presented. A porous and hierarchical micro-nanostructured silica basecoat (sol-gel) was first formed by EAD of a methyltriethoxysilane (MTES) precursor solution on a copper substrate. Then, a superhydrophobic top-coat (E-MTES/PFOTS) was prepared with 1H,1H,2H,2H-Perfluorooctyltriethoxysilane (PFOTS) for low surface energy. The superhydrophobic coating exhibited anti-stain properties against milk, cola, and oil, with contact angles of 151°, 151.5°, and 129°, respectively. The EAD deposition potential and duration were effective in controlling the microscopic morphology, surface roughness, and coating thickness. The E-MTES/PFOTS coatings exhibited chemical stability against acids, bases, and abrasion resistance by sandpaper. The proposed 2-layer coating system exhibited strong chemical bonding at the two interfaces and provided a brush-like surface morphology with long-lasting superhydrophobicity. The developed method would provide an environment-friendly and expedient process for uniform protective coatings on complex surfaces.

Gelation Chemistry and Phase Development of Chemical Solution Deposition-Derived Sm-Doped BiFeO3 Thin Films: The Role of Sm Dopant

Gelation chemistry and the related phase development play important roles in chemical solution-derived ferroelectric oxide thin films. Here, we report a detailed study on the gelation chemistry behavior of sol–gel Sm-doped bismuth ferrite (Bi1–xSmxFeO3–BSFO) thin films. The precursor solutions were first investigated to elucidate the role of Sm dopant on film molecular networks. The hydrolysis and esterification reactions were found to be dependent on the metal cation species; compared to Bi3+ and Fe3+, the introduction of Sm3+ accelerates the esterification reaction. The subsequent crystallization process of deposited BSFO films was further analyzed to understand the phase structure development as a function of Sm dopant concentration and heating temperature. (00l)-oriented BSFO phases were observed in all films. With the increase of the Sm dopant, the paraelectric orthorhombic (O) phase and antipolar phase start to form at x = 0.10. The domain structure and ferroelectric properties show a concomitant dependence on the Sm doping component. Upon increasing the Sm doping component, the virgin domain amplitude decreases, while the poled domains show an enhanced amplitude. The amplitude variation between the unpoled and poled domains is as high as 760% at x = 0.10. The ferroelectric properties of BSFO films are greatly improved due to the Sm doping. At x = 0.14, a fully developed polarization hysteresis loop is acquired. With the further increase of Sm composition to 0.15, a slightly distorted loop, which indicates an electric-field-induced paraelectric O phase to ferroelectric R phase transition, is first observed in chemical solution deposition (CSD)-derived BSFO films. These results provide a deep insight into the development of rare-earth-doped BFO films through a commercially viable chemical solution method.

Robust and Scalable In Vitro Surface Mineralization of Inert Polymers with a Rationally Designed Molecular Bridge.

The artificial integration of inorganic materials onto polymers to create the analogues of natural biocomposites is an attractive field in materials science. However, due to significant diversity in the interfacial properties of two kinds of materials, advanced synthesis methods are quite complicated and the resultant materials are always vulnerable to external environments, which limits their application scenarios and makes them unsuitable for scalable production. Herein, we report a simple and universal approach to achieve robust and scalable surface mineralization of polymers using a rationally designed triple functional molecular bridge of fluorosilane, 3-[(perfluorohexyl sulfonyl) amino] propyltriethoxy silane (PFSS). In a two-step solution deposition, the fluoroalkyl and siloxane of the PFSS take charge of its adhesion and immobilization onto polymers by hydrophobic interaction and wrapping-like chemical cross-linking, and then the assembly and growth of inorganic nanoclusters for integration are achieved by strong chemical coordination of PFSS sulfonamide. The versatile mineralization of inorganic oxides (e.g., TiO2, SiO2, and Fe2O3) onto chemically inert polymer surfaces was realized very well. The resultant mineralized materials exhibit robust and multiple functionalities for hostile applications, such as hydrophilic membranes for removing oils in strong acidic and alkaline wastewaters, fabrics with advanced anti-bacteria for healthy wearing, and plates with strong mechanical performance for better use. Experimental results and theoretical calculations confirmed the homogenous distribution of the PFSS onto polymers via cross-linking for robust coordination with inorganic oxides. These results demonstrate a skillful enlightenment in the design of high-performance mineralized polymer materials used as membranes, fabrics, and medical devices.