Titanate Nanostructures Research Articles

From mixed brookite/anatase TiO2 nanopowder to sodium titanates: Insight into morphology, structure, and photocatalytic performance

A method to obtain sodium titanate nanoribbons starting from a mixture of brookite and anatase TiO₂ nanopowder is described. As-prepared TiO2 nanopowder with a major brookite phase was used as a precursor in an alkaline hydrothermal approach, where the temperature was kept at 200 °C. The influence of hydrothermal treatment and consequent annealing temperature (T = 500 °C) on the crystal structure, phase composition, and morphology of samples were investigated by X-ray powder diffraction (XRPD), Raman and FTIR spectroscopy, and electron microscopy techniques (FESEM, HRTEM). All these methods point out that the hydrothermally treated sample, containing the NaTi3O6(OH)(H2O)2, Na2Ti3O7, and Na2Ti9O19, is dominated by layer-structured sodium hydroxititanate dihydrate. The annealing leads to the formation of rare sodium titanates, Na3Ti6O13 and Na2Ti9O19, with tunnel structures where the hexatitanate with increased sodium content prevails. The photocatalytic activity of synthesized nanostructures was tested in the degradation process of Reactive Orange (RO16) azo-dye upon UV excitation. It appears that photocatalytic activity is lower after hydrothermal treatment, but subsequent annealing makes sodium titanate nanoribbons faster in the degradation of RO16. The research implies that these sodium titanate nanostructures are promising photocatalytic materials and should be considered in the future for removing different pollutants from water.

Synthesis and characterization of barium titanate nanoplatelets/polyvinylidene fluoride nanocomposite for piezoelectric properties

AbstractBarium titanate (BaTiO3) nanostructures with a tetragonal structure have unique mechanical and piezoelectric properties. BaTiO3 nanoplatelets (BTNPs) were synthesized via the precipitation of the hydroxide (Ba‐Ti‐OH) precursor, which was subsequently subjected to hydrothermal treatment. Polyvinylidene fluoride (PVDF) granules and BTNPs powder were compounded through melt‐mixing within a laboratory internal mixer to PVDF/BTNP nanocomposite. The dispersion of BTNPs were analyzed using FE‐SEM images. The examination of the polycrystalline structure of a PVDF/BTNP nanocomposite involved the utilization of FTIR, DSC, and XRD measurements. Further, the tensile test was carried out to study the mechanical properties of the nanocomposites. The piezoelectric tests showed that the PVDF nanocomposite with 10 wt.% of BTNP exhibited the highest output voltage and current due to its maximum crystallinity. The measured current increased from 0.03 μA for PVDF to 0.22 μA for PVDF/BTNP nanocomposite and further to 0.34 after polling. PVDF's piezoelectric properties experienced an 11‐fold enhancement due to alterations in its crystalline structure. Power density improved by 644% (7.5 times), and piezoelectric sensitivity rose by 173%. Consequently, the PVDF/BTNP nanocomposite demonstrates significant potential for applications in electronics and energy harvesting.Highlights Unique Tetragonal nanoplatelets produced via controlled BTNP synthesis. 10% BTNP enhances nanocomposite crystallinity by 22.7% PVDF‐10 displays increase in both voltage and current, enhancing piezoelectricity. Nanocomposites show promise for energy and electronics.

Synthesis of oxygen vacancies-enriched titanate nanostructures and their potassium storage properties study

The commonly adopted high-temperature calcination prior to electrode fabrication decreases the electrochemical activities of titanium-based layered oxides, a class of promising electrode materials with low cost and decent performance, through their microsctructure aggregations and interlayer spacing contractions. Here we present a low temperature method for generating abundant oxygen vacancies in K2Ti2O5 nanostructures (referred to as ov-KTO) as the electrode material to overcome this limitation. The rich vacancy in ov-KTO nanomaterial contributes increased interlayer spacing and heightened electrical conductivity compared to the bulk counterpart. It also causes a significance of redox Ti3+/Ti4+ reaction for ov-KTO in water-in-salt electrolyte. These advancements lead us to construct a high-performance ov-KTO//active carbon assembled aqueous hybrid supercapacitor. The device shows large working voltage window, impressive energy density, long lifespan and wide operation temperature, demonstrating its comparable with the aprotic-electrolyte supercapacitor in performance but being safer and more cost-effective.

Molten salt synthesis of MXene-derived hierarchical titanate for effective strontium removal

The removal and recovery of radioactive Sr(II) from wastewater and seawater has been of great concern due to the negative environmental impacts of nuclear energy development and the potential risk of nuclear accidents. Herein, a facile molten salt synthesis strategy was developed to systematically investigated the reaction of different types of MXenes with nitrates. Among the products, K+ intercalated hierarchical titanate nanostructures (K-HTNs) obtained from the direct chemical transformation of multilayered Ti3C2Tx exhibited unique layered structures, good physicochemical properties, and outstanding adsorption performance for Sr(II). The maximum adsorption capacity of Sr(II) by K-HTNs reached 204 mg·g−1 at ambient temperature, and the good regeneration and reusability of the titanate was also demonstrated. K-HTNs showed preferential selectivity for Sr(II) in different environmental media containing competing ions, and the removal efficiency of Sr(II) in real seawater was as high as 93.3 %. The removal mechanism was elaborated to be the exchange of Sr2+ with K+/H+ in the interlayers of K-HTNs, and the adsorbed Sr(II) had a strong interaction with Ti−O− termination on the titanate surface. Benefiting from the merits of rapid and scalable synthesis and excellent adsorption performance, MXene-derived K-HTNs have broad application prospects for the purification of 90Sr-contaminated wastewater and seawater.

Emerging silver-doped strontium titanate nanostructures as photocatalysts for the degradation of organic pollutants under visible light

The primary objective of this research is to explore a novel and straightforward method, known as one-pot hydrothermal synthesis, for producing photocatalyst nanocomposite materials consisting of perovskite-based silver doped strontium titanate (Ag–SrTiO3). The investigation focused on assessing the photocatalytic effectiveness and recyclability of these nanocomposites when employed to eliminate ciprofloxacin (CIP) antibiotics under visible-light exposure. The XRD of the Ag–SrTiO3 exhibited a highly crystalline nature with stacked cube morphology, which was also revealed through the SEM technique. The TEM analysis showed the characteristics of the materials such as particle shape, and the SAED pattern confirmed the crystalline phases. The essential reaction parameters, including the amount of catalyst used, the solution's pH level, and the initial pollutant concentration, were altered to identify the most favorable conditions for photodegradation. Furthermore, this composite catalyst displayed excellent stability and could be reused, achieving an 84.5 % removal of CIP after five consecutive cycles. Through scavenger tests, it was determined that photogenerated holes (h+) and superoxide free radicals (•O2) played key roles in the degradation process. This research offers valuable insights into designing highly efficient nanomaterials for the removal of antibiotic degradation from wastewater, and it proposes a possible reaction mechanism.

3D printed ultrahigh aspect ratio lead zirconate titanate (PZT) nanostructures for nano-Newton force sensing

Lead zirconate titanate (PZT) has attracted great attention due to the recognition of its impact on extensive applications in high-resolution force sensing. However, its brittleness and the preparation challenges of ultrahigh aspect ratio nanostructures have hindered their practical application. Here, we present a nanoscale electrohydrodynamic jet 3D printing method capable of tailoring ultrahigh aspect ratio hierarchical PZT nanostructures with controllability, fast, and inexpensive. Thermally in situ curing and vertical shear stress of high viscous jet avoid introducing defects in the post-treatment sintering process and minimize internal defects providing a relatively smooth surface. The printed ultrahigh aspect ratio PZT structure exhibits Young's modulus of 99.4 GPa, which was smaller than the block PZT, greatly improving its flexibility. The experimental results show that it can detect forces in the nano-Newton scale. This finding provides a generally applicable strategy for preparing high-performance ultrahigh aspect ratio nanoscale piezoelectric materials for MEMS devices.

Defect evolution on the activity of samarium doped Na2TinO2n+1 with different sodium/titanium ratio for photocatalytic degradation of fluoroquinolones drugs, toxicity assessments and eco-toxicity prediction

In this study, samarium (Sm) doped sodium titanate (Na2TinO2n+1) with different Na/Ti molar ratios {n: 3, 6, and 9} were synthesized by using sol-gel method. The prepared nanostructures were characterized by XRD, SEM, EDS, BET, UV–vis, EIS and photoluminescence analysis. XRD analysis depicts the Na2Ti6O13 was the main substance, while Sm–Na2Ti9O19 contained a minor proportion of Na2Ti6O13, and rutile phase TiO2. The pore size distribution for all samples is between 2 nm and 20 nm, indicating that most of the pores are in the range of meso porosity. The adsorption-desorption isotherms shows the mesoporous properties of the prepared samples. The band gap energies for samarium doped sodium titanate were lower than the sodium titanate nanostructures. The productivity of hydroxyl radicals on the samarium doped sodium titanates was in the sequence Sm–Na2Ti9O19 > Sm–Na2Ti6O13 > Sm–Na2Ti3O7. The different samarium doped sodium titanates samples were utilized for degradation ofloxacin and ciprofloxacin under UV light irradiation. The results showed that the complete degradation ofloxacin (94.2 %) and ciprofloxacin (99.7 %) were obtained by using Sm–Na2Ti9O19 within 70 min, while the degradation efficiency of Sm–Na2Ti6O13 and Sm–Na2Ti3O7 were lower than Sm–Na2Ti9O19 nanostructures. Also, the marine microalgaes growth rate and biotoxicity of the Sm-doped sodium titanates were investigated on Chaetoceros calcitrans, and Nannochloropsis oculata. The results showed that high concentration of the samarium doped sodium titanates were inhibited the algae growth rate.

Machine learning approach for predicting electrical features of Schottky structures with graphene and ZnTiO3 nanostructures doped in PVP interfacial layer

In this research, for some different Schottky type structures with and without a nanocomposite interfacial layer, the current–voltage (I–V) characteristics have been investigated by using different Machine Learning (ML) algorithms to predict and analyze the structures’ principal electric parameters such as leakage current (I0), barrier height ({varphi }_{B0}), ideality factor (n), series resistance (Rs), shunt resistance (Rsh), rectifying ratio (RR), and interface states density (Nss). The interfacial nanocomposite layer is made by composing polyvinyl-pyrrolidone (PVP), zinc titanate (ZnTiO3), and graphene (Gr) nanostructures. The Gaussian Process Regression (GPR), Kernel Ridge Regression (KRR), Support Vector Regression (SVR), and Artificial Neural Network (ANN) are used as ML algorithms. The ML techniques training data are obtained using the thermionic emission method. Finally, by comparing the experimental and predicted results, the performance of the different ML algorithms in predicting the electrical parameters of Schottky diodes (SDs) has been compared to find the optimized ML algorithm. The ML predictions of basic electrical parameters by almost all algorithms are in good agreement with the actual values, while the SVR model has predicted closer values to the corresponding actual ones. The obtained results show that the quantity of the leakage current and Nss for MS type SD decreases, and φB0 increases with the interfacial layer usage, especially with graphene dopant.

Glycerol carbonate synthesis over nanostructured titanate catalysts: Effect of morphology and structure of catalyst

The indirect conversion of CO2 into glycerol carbonate using DMC was investigated using pristine sodium titanate nanotubes (NaTNT) and nanostructured titanates (calcined NaTNT at different temperatures) as catalysts. The calcination changes the morphology of the nanostructured titanates, between 200 and 400 °C the nanotubes shape is retained, however above these temperatures (500 and 600 °C) nanoribbons were identified, as well as nanorods obtained at 700 °C. A significant decrease in specific surface area and total pore size in temperatures up 500 °C was also observed. Furthermore, a decrease in the Ti+4/Ti+2 ratio and in the binding energy of Ti 2p3/2 and Ti 2p1/2 were observed, indicating an increase in the electron density and consequently increase in the Lewis acidity character of the titanium atom. All the nanostructured titanates showed good catalytic activity with glycerol conversion and GC selectivity above 90%. The results of the recycling showed that the nanostructured catalysts retained a good catalytic activity with high glycerol conversion (> 90%) although the GC selectivity decreased due the formation of glycidol, a high value-added by-product.

Role of graphene nanoparticles on the electrophysical processes in PVP and PVP:ZnTiO3 polymer layers at Schottky diode (SD)

In this paper, a polyvinyl pyrrolidine (PVP) polymer layer is inserted between the metal–semiconductor (MS) structure to manufacture a metal–polymer–semiconductor (MPS) structure or Schottky diode (SD). The zinc titanate and graphene nanostructures were doped into the PVP layer individually and together to improve the electrical performance of the MPS-type SD. The crystalline size, surface morphology, and band gap energy of the ZnTiO3 nanostructures are examined by the x-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and ultraviolet–visible (UV–Vis) spectroscopy, respectively. It is common to measure the current–voltage (I–V) features (at ±3 V) of these five structures for calculating the reverse saturation current (I 0), barrier height, ideality factor (n), series (R s), and shunt (R sh) resistances as the main electrical parameters utilizing the thermionic emission, Norde, and Cheung models. Also, the forwarded-bias energy-dependent surface states density (N ss) and the forward/reverse biased current conduction mechanisms are studied and discussed. The rectifying ratio (RR) of Al/PVP:Gr-ZnTiO3/p-Si SD has the highest increase among these five SDs while the lowest I 0 and highest R sh are related to the Al/PVP:Gr/p-Si (MPS2) and Al/PVP:ZnTiO3/p-Si (MPS3) SDs, respectively. Therefore, doping Gr into the PVP interlayer increases the electrical conduction in the SDs although PVP:Gr-ZnTiO3 polymer layer improves the RR of SDs.

Enhanced charge carrier transfer process in nickel titanate nanostructures for environmental remediation of industrial dye.

The effective charge carrier transfer process in one-dimensional (1D) NiTiO3 nanofibers and NiTiO3 nanoparticles was demonstrated experimentally, showcasing an effective photocatalytic enhancement under visible light ambience. The rhombohedral crystal structure of NiTiO3 nanostructures was confirmed using X-ray diffractometer (XRD). The morphology and optical characteristics of the synthesized nanostructures were characterized using scanning electron microscopy (SEM) and UV-visible spectroscopy (UV-Vis). Nitrogen adsorption-desorption analysis corresponding to NiTiO3 nanofibers showcased porous structures with an average pore size of ~3.9 nm. The photoelectrochemical (PEC) measurement studies revealed an enhanced photocurrent for the NiTiO3 nanostructures, confirming enhanced charge carriers transportation in fibers than in particles due to the delocalized electrons in the conduction band, thereby hindering the photoexcited charge carrier's recombination. The photodegradation efficiency of methylene blue (MB) dye under the visible light irradiation revealed an enhancement in the rate of degradation for NiTiO3 nanofibers when compared to NiTiO3 nanoparticles.

KOH-Based Hydrothermal Synthesis of Iron-Rich Titanate Nanosheets Assembled into 3D Hierarchical Architectures from Natural Ilmenite Mineral Sands

The synthesis of titanate nanostructures from low-cost mineral precursors is a topic of continuous interest, considering not only their fundamental aspects but also the benefits of incorporating such nanomaterials in a wide variety of applications. In this work, iron-rich titanate nanosheets were synthesized from Ecuadorian ilmenite sands (ilmenite–hematite solid solution-IHSS) through an alkaline hydrothermal treatment (AHT) using potassium hydroxide (KOH). The effect of the duration of the KOH-AHT was assessed at 180 °C for 24, 48, 72, and 96 h. The morphology evolution over time and the plausible formation mechanisms of titanate nanostructures were discussed. The most significant morphological transformation was observed after 72 h. At this time interval, the titanate nanostructures were assembled into well-defined 3D hierarchical architectures such as book-block-like arrangements with open channels. Based on X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) analyses, it was determined that these nanostructures correspond to iron-rich layered titanates (Fe/Ti mass ratio of 7.1). Moreover, it was evidenced that the conversion of the precursor into layered nanostructures was not complete, since for all the tested reaction times the presence of remaining IHSS was identified. Our experiments demonstrated that the Ecuadorian ilmenite sands are relatively stable in KOH medium.

Structural, optical, and electrical properties of proton intercalation H+/Na+ phases in nanostructured titanates induced by pH during hydrothermal synthesis

In search of a promising alternative to manufacture anodes for sodium-ion batteries, a study of the pH variation during hydrothermal synthesis of nanostructures of sodium titanate is presented. In particular, structural, optical and electrical properties of these materials are assessed when varying the pH for two different synthesis conditions. A mixture of phases was found, in agreement with ( N a , H ) 2 T i 3 O 7 ⋅ n H 2 O , and its cause is attributed to the proton( H + )/sodium( N a + ) exchange and the intercalation of structural water. Also, changes in the morphology of the structural phases were observed, for example the phase with lower interlaminal distance appears to be nanorods, instead of nanotubes. The relative weight between phases and the direct band gap can be tuned by controlling synthesis conditions, in particular pH conditions. An enhancement of new processes in the electrical response and the suppression or enhancement of some defect due to the mixture of phase is also discussed. Additionally, the changes in electrical properties over a possible operation temperature range of a potential device, between −30 °C and 50 °C is reported. It was found that the changes in impedance in the proposed temperature range are of the order of 25 % of the modulus. This work shows how the final N a + content in the sample alters its optical and electrical properties, which are determinant in its performance as an anode. • Effect of pH during the synthesis of sodium titanate nanostructure. • Mixture of phases concordant with (Na, H) 2 Ti 3 O 7 .nH 2 O. • Mixture of phases regulates optical and electrical properties. • Direct Band gap could be tuned with pH during synthesis. • Study of the electrical impedance in the operation temperature range.

Enriched second-harmonic generation in meta-phase barium titanate nanostructures synthesized by sol-gel hydrothermal method

This study reports on the second harmonic generation (SHG) of barium titanate (BaTiO3) nanoparticles synthesized by a low-cost and easily-accessible sol-gel hydrothermal method at different temperatures (100–250 °C). According to the powder X-ray diffraction (XRD) pattern, all of the prepared samples had meta-phase without a center of symmetry, and the crystal structure changes from simple cubic to rhombohedral at different temperatures. In addition to XRD, differential scanning calorimetry (DSC) confirms the meta-phase in BaTiO3 by showing a significant phase shift indicating structural distortion. The variation in particle size was observed from transmission electron microscope (TEM) and the selected area electron diffraction (SAED) pattern as well supports the presence of structural distortion in the nanomaterials. The phase variation in BaTiO3 has not only affected its structure but also creates a disorder in its magnetic properties by changing it from paramagnetic to ferromagnetic for different synthesizing temperatures. This was determined with a vibrating sample magnetometer (VSM) and electron paramagnetic resonance (EPR) techniques. As a consequence of this structural deformation, particle size variation, and magnetic phase transition the second harmonic generation (SHG) conversion efficiency of BaTiO3 has been improved. Hence, this technique for synthesizing nanomaterials could be a promising candidate for fabricating bio-compatible imaging probes and coherent bio-markers in the field of medicine and electronics.

Optimal growth of sodium titanate nanoflower on TiO2 thin film for the fabrication of a novel Ti/TiO2/Na2Ti3O7 photoanode with excellent stability

This study reports the effect of the Ti source (Ti foil or TiO 2 thin layer) and NaOH concentration on the growth of sodium titanate nanostructures via hydrothermal treatment to improve the photoelectrochemical (PEC) water splitting performance. An optimal condition to grow sodium titanate nanoflower composed of ultrathin nanosheets on the surface of the thin TiO 2 film led to the formation of a novel nanocomposite TiO 2 /Na 2 Ti 3 O 7 photoelectrode with great adhesion of the two phases. The Ti/TiO 2 /Na 2 Ti 3 O 7 photoanode demonstrated a significant enhancement in photocurrent density and shifted the onset potential to a more negative value compared to the pure Ti/TiO 2 and Ti/Na 2 Ti 3 O 7 samples. This noticeable improvement is attributed to the suitable band alignment between the TiO 2 and Na 2 Ti 3 O 7 phases and their direct contact with the Ti foil, as well as the large surface area of nanoflower sodium titanate, which significantly facilitate the generation, separation, and transfer of photogenerated electrons from the active phases to the substrate. More interestingly, the prepared photoanode retained its initial photocurrent density even after 16 h. An ion-exchange method and calcination treatment were used at different temperatures to convert the Na 2 Ti 3 O 7 phase in the Ti/TiO 2 /Na 2 Ti 3 O 7 photoanode to TiO 2 to investigate the role of type II heterojunction for efficient photogenerated charge carrier separation in this photoanode. It was concluded that converting Na 2 Ti 3 O 7 into TiO 2 in the Ti/TiO 2 /Na 2 Ti 3 O 7 system would reduce its PEC performance due to the formation of a pure phase of TiO 2 in the Ti/TiO 2 /TiO 2 photoanode. • The Ti/TiO 2 /Na 2 Ti 3 O 7 photoanode demonstrated a significant enhancement in photocurrent density. • The Ti/TiO 2 /Na 2 Ti 3 O 7 photoanode retained its initial photocurrent density even after 16 h. • Ti/TiO 2 /Na 2 Ti 3 O 7 showed a photocurrent density of around 0.46 mA/cm 2 at 0.3 V vs. Ag/AgCl. • Any morphological and phase changes in Ti/TiO 2 /Na 2 Ti 3 O 7 reduce its photocatalytic activity.

Synthesis, characterization and electrochemical sensors application of Tb2Ti2O7 nanoparticle modified carbon paste electrode for the sensing of mefenamic acid drug in biological samples and pharmaceutical industry wastewater

Today, in most fields, wide research has been done in the manufacture of biosensors and the detection of various types of substances, including drugs. Nevertheless, the analytical detection of drugs from a biological sample by a simple and portable method for on-site detection is still important and very challenging. This paper investigates the electrochemical determination of the mefenamic acid (MEF), with a novel carbon paste electrode modified with terbium titanate nanostructures (TTN/CPE). The effect of the capping agent on the morphology and size of terbium titanate synthesized from terbium nitrate in the presence of ethylene glycol (EG) as a stabilization agent is investigated. The as-produced nanostructures are characterized by X-ray diffraction (XRD), Fourier transforms infrared (FT-IR) spectroscopy, energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM). Electrochemical studies in optimized conditions indicate MEF has two linear responses in the range of 1.0 × 10−2–4.0 × 102 μM with a detection limit of 2.4 nM at the surface of TTN/CPE. The suggested sensor reveals good sensitivity, selectivity, stability, and reproducibility and can be utilized for some important biological samples and wastewater with satisfactory results.

Piezoelectric Nanogenerators based on Lead Zirconate Titanate nanostructures: an insight into the effect of potential barrier and morphology on the output power generation

The high internal resistance of the perovskite materials used in Nanogenerators (NGs) lowers the power generation. It severely restricts their application for mechanical energy harvesting from the ambient source. In this work, we demonstrate a flexible Piezoelectric NG (PENG) with an improved device structure. Hydrothermally grown one-dimensional Lead Zirconate Titanate (Pb(ZrTi)O3) of different morphologies are used as the generating material. The morphology of the PZT nanostructures, engineered from nanoparticles to needle-shaped nanowires to increase the surface to volume ratio, provides effective mechanical contact with the electrode. The reduction of the internal resistance of the PENG has been achieved by two ways: (i) fabrication of interdigitated electrodes (IDE) to increase the interfacial polarization and (ii) lowering of Schottky barrier height (SBH) at the junction of the PZT nanostructure and the metal electrode by varying the electrode materials of different work functions. We find that lowering of the SBH at the interface contributes to an increased piezo voltage generation. The flexible nano needles-based PENG can deliver output voltage 9.5 V and power density 615 μW cm−2 on application low mechanical pressure (∼1 kPa) by tapping motion. The internal resistance of the device is ∼0.65 MΩ. It can charge a 35 μF super-capacitor up to 5 V within 20 s. This study provides a systematic pathway to solve the bottlenecks in the piezoelectric nanogenerators due to the high internal resistance.

Enriched Second-Harmonic Generation in Meta-Phase Barium Titanate Nanostructures Synthesized by Sol-Gel Hydrothermal Method

Enriched Second-Harmonic Generation in Meta-Phase Barium Titanate Nanostructures Synthesized by Sol-Gel Hydrothermal Method

Development of Cell-Carrying Magnetic Microrobots with Bioactive Nanostructured Titanate Surface for Enhanced Cell Adhesion.

Cell-carrying magnet-driven microrobots are easily affected by blood flow or body fluids during transportation in the body, and thus cells often fall off from the microrobots. To reduce the loss of loaded cells, we developed a microrobot with a bioactive nanostructured titanate surface (NTS), which enhances cell adhesion. The microrobot was fabricated using 3D laser lithography and coated with nickel for magnetic actuation. Then, the microrobot was coated with titanium for the external generation of an NTS through reactions in NaOH solution. Enhanced cell adhesion may be attributed to the changes in the surface wettability of the microrobot and in the morphology of the loaded cells. An experiment was performed on a microfluidic chip for the simulation of blood flow environment, and result revealed that the cells adhered closely to the microrobot with NTS and were not obviously affected by flow. The cell viability and protein absorption test and alkaline phosphatase activity assay indicated that NTS can provide a regulatory means for improving cell proliferation and early osteogenic differentiation. This research provided a novel microrobotic platform that can positively influence the behaviour of cells loaded on microrobots through surface nanotopography, thereby opening up a new route for microrobot cell delivery.

Scalable Lanthanum Titanate (La2Ti2O7) nanostructures as UV photodetectors

Scalable Lanthanum Titanate (La2Ti2O7) nanostructures as UV photodetectors