Search

Solar energy-powered adsorption-based atmospheric water harvesting (ABAWH) is an emerging technology for freshwater production, especially in water-scarce regions that are remote and landlocked. Numerous water adsorbents have been used in ABAWH devices to convert molecule to liquid water. However, it is still challenging to harvest water from the air in cold winter, owing to the water adsorption of sorbents decreasing significantly at low temperature. Herein, we designed and fabricated an ABAWH device by integrating composited ionic liquids (CILs) with carbon nanotubes (CNTs) photothermal materials on the surface of cotton rod fibers. CILs extract water from the air. CNTs enable light-to-heat conversion and drive the solar evaporation process. Importantly, the cotton rods offer a backbone porous structure to maintain its internal temperature at 20 °C under solar irradiation, and thus promote the water adsorption performance of CILs at low environmental temperature. Freshwater is successfully harvested under environment temperature of 6 °C, 30% RH and solar irradiation intensity of 0.6 kW m−2. The water yield can achieve 1.49 kg per m2 per day in an outdoor environment. We believe that the ABAWH device offers a promising approach to effectively harvest water from the air at low temperature and humidity conditions.

Simultaneously monitoring label-free nanoparticles (NPs) and fluorescent biomolecules inside the live cell in real time is challenging because both imaging methods require different instrumentation and measuring principles. Here we report a novel scattered light imaging (SLi) technique that allows label-free NPs to be monitored using a conventional confocal microscope. The method shows a high spatial resolution and can distinguish label-free silver nanoparticles (AgNPs) with a 10 nm size difference in live cells. We performed SLi to observe the uptake, movement, distribution, and transformation of AgNPs in live cells at a single-particle level. The method is applicable to accurately track the localization of a variety of nanomaterials inside the cell. With this approach, label-free NP and fluorescent-labeled biomolecules are imaged simultaneously making it possible to real-time monitor nanobio interactions.

Infections caused by Staphylococcus aureus (S. aureus) have a significant contribution to delayed wound healing, and thus raise a particular public health concern. Controlling the interaction between bacterial and tissue cells is considered as a key factor to affect the critical colonization and spreading invasive infection. Thus, we designed and fabricated a manganese dioxide nanowire monolayer based on the Langmuir–Blodgett method. The nanowire monolayer was functionalized by and transferred onto the surface of a tetrabromobisphenol A (TBBPA)-embedded polydimethylsiloxane (PDMS) membrane. The as-prepared composite membrane could decrease the bacterial invasion by capturing and killing the bacteria on its surface. An average capture efficiency of 90% was observed. 87% of the captured bacteria were killed according to the extended release of TBBPA from the PDMS membrane. The results from in vivo experiments demonstrate that the as-prepared antibacterial membrane could promote the infected wound healing in a mouse model. This IgG-functionalized MnO2 nanowire-coated TBBPA-embedded PDMS membrane appears promising in potential clinical applications against external infections caused by S. aureus.

Li metal is considered a highly desirable anode for next-generation high-energy-density rechargeable lithium batteries. However, irregular Li dendrite formation and infinite relative volume changes prevent the commercial adoption of Li-metal anodes. Here, electrophoretic deposition of black phosphorus (BP) on commercial Cu foam (BP@Cu foam) is reported to regulate Li nucleation for the first time. First-principles calculations reveal that the unique two-dimensional (2D) structure of BP is beneficial to Li intercalation and propagation. Compared with the random Li nucleation and growth on bare Cu foam, Li ions are preferably confined into the BP layers, which induces uniform Li nucleation at the early stage of the Li deposition and guides the following lateral Li growth on BP@Cu foam. In addition, the three-dimensional (3D) porous and conductive framework of Cu foams further mitigate the volume change and dissipate the current density. Attributing to these merits, the BP@Cu foam exhibits significantly enhanced Coulombic efficiency and cycling stability compared with bare Cu foam. In the full-cell configuration paired with a Li4Ti5O12 or LiFePO4 cathode, the BP@Cu foam also boosts the battery performances. This work provides new insights into the development of BP and other elaborate 2D materials for achieving dendrite-free Li-metal anodes.

Controllable three-dimensional villose titanium dioxide architectures grown on carbon textiles are fabricated by a facile one-step in-situ hydrothermal method at low temperatures. It has in fact been proven to be an effective method to reduce self-aggregation and promote lithium-ion intercalate/extract via building 3D architectures based on 2D conductive materials. More importantly, the freestanding electrodes without any addition of conductive agents and polymeric binders reveal significant improvement in high-rate capacity and cycling performance.

Herein, we demonstrate a sustainable strategy for scalable production of α-Fe2O3 nanocrystals on flexible carbon textiles via controllable chemical bath deposition process. The assembly of α-Fe2O3 nanocrystals is densely anchored onto the carbon textiles, and the temperature-dependent mass loading and crystal size of α-Fe2O3 are systematically investigated. As an integrated electrode for lithium-ion batteries, the optimized Fe2O3@CTs with ultrathin three-dimensional interconnected porous architectures achieves significantly enhanced cycling performance and rate capability attributing to the improved stability, electronic interconnection, and shortened solid state diffusion pathway for Li+ ions/electrons. After the reactivation of the precursor, the Li-ion batteries based on the recycled Fe2O3@CTs exhibits electrochemical performance with no decay compared to that of the devices based on the fresh products. This sustainable methodology, considering material abundance, eco-efficiency, synthetic approach and scalability, is of crucial importance to both academy and industry for achieving high-performance lithium-ion batteries.

Background: Circulating tumor cells (CTCs) are a burgeoning topic in cancer biomarker discovery research with minimal invasive blood draws. CTCs can be used as potential biomarkers for disease prognosis, early cancer diagnosis and pharmacodynamics. However, the extremely low abundance of CTCs limits their clinical utility because of technical challenges such as the isolation and subsequent detailed molecular and functional characterization of rare CTCs from patient blood samples. Methods: In this study, we present a novel density gradient centrifugation method employing biodegradable gelatin nanoparticles coated on silicon beads for the isolation, release, and downstream analysis of CTCs from colorectal and breast cancer patients. Results: Using clinical patient/spiked samples, we demonstrate that this method has significant CTC-capture efficiency (>80%) and purity (>85%), high CTC release efficiency (94%) and viability (92.5%). We also demonstrate the unparalleled robustness of our method in downstream CTC analyses such as the detection of PIK3CA mutations. Conclusion: The efficiency and versatility of the multifunctional density microbeads approach provides new opportunities for personalized cancer diagnostics and treatments.

We have demonstrate a facile strategy to achieve the controllable morphology transformation of TiO2 induced by the introduction of multi-walled carbon nanotubes. The intervention of functionalized carbon nanotubes (CNTs) is key to the formation of TiO2 nanopompons. Furthermore, the size of the obtained TiO2 nanopompons can be controlled by modulating the CNT amounts. The obtained TiO2 nanopompon-embedded CNT hybrid networks (TNP@CNT HNs) incorporate the advantages of hierarchical nanostructures and 3D interconnected conductive networks, including high surface area, uniform particle/pore size, short Li+ ion/electron transport pathway, and high electronic conductivity. These TNP@CNT HN-based anodes achieve a significant improvement in the insertion/extraction of Li+ ions and electrochemical performances via optimizing the CNT amounts and the size of the TiO2 nanopompons. The lithium-ion batteries based on the optimized TNP@CNT HNs exhibit excellent cycling stability (keeping approximately 200 mA h g−1 after 500 cycles at 2C rate, 1C = 170 mA g−1) and rate performance (approximately 125 mA h g−1 at 20C rate with a capacity retention of 77% after 2000 cycles).

We report here the antimicrobial ability of tetrabromobisphenol A (TBBPA) against Gram-positive bacteria without detectable resistance. Microscopy imaging and gene analysis reveal that the bacterial cell wall is the target of TBBPA. Structure-activity studies of TBBPA and its analogues relate the observed antimicrobial activity to the halogen substitution neighboring the phenolic hydroxyl group.

Well-organized epsilon-MnO2 hollow spheres/reduced graphene oxide (MnO2HS/RGO) composites have been successfully constructed via a facile and one-pot synthetic route. The ε-MnO2 hollow spheres with the diameter of ∼500 nm were grown in situ with homogeneous distribution on both sides of graphene oxide (GO) sheets in aqueous suspensions. The formation mechanism of the MnO2HS/RGO composites has been systematically investigated, and a high specific capacitance and good cycling capability were achieved on using the composites as supercapacitors. The galvanostatic charge/discharge curves show a specific capacitance of 471.5 F g(-1) at 0.8 A g(-1). The hollow structures of ε-MnO2 and the crumpled RGO sheets can enhance the electroactive surface area and improve the electrical conductivity, thus further facilitating the charge transport. The MnO2HS/RGO composite exhibits a high capacitance of 272 F g(-1) at 3 A g(-1) (92% retention) even after 1000 cycles. The prominent electrochemical performance might be attributed to the combination of the pseudo-capacitance of the MnO2 nanospheres with a hollow structure and to the good electrical conductivity of the RGO sheets. This work explores a new concept in designing metal oxides/RGO composites as electrode materials.

Tetrabromobisphenol A (TBBPA) is a brominated flame retardant with selective antimicrobial activity against Gram-positive bacteria. We show that TBBPA exerts bactericidal effects by damaging the cell wall and membrane of Staphylococcus aureus (SA) without inducing antimicrobial resistance. In vivo skin infection assays indicate that a low dose of TBBPA could contribute to wound closure and attenuate SA infection and inflammatory infiltration. TBBPA has potential for use as an antimicrobial agent against Gram-positive pathogens.

Three-dimensional branched TiO2 architectures (3D BTA) with controllable morphologies were synthesized via a facile template-free one-pot solvothermal route. The volume ratio of deionized water (DI water) and diethylene glycol in solvothermal process is key to the formation of 3D BTA assembled by nanowire-coated TiO2 dendrites, which combines the advantages of 3D hierarchical structure and 1D nanoscale building blocks. Benefiting from such unique structural features, the BTA in full bloom achieved significantly increased specific surface areas and shortened Li(+) ion/electrons diffusion pathway. The lithium-ion batteries based on BTA in full bloom exhibited remarkably enhanced reversible specific capacity and rate performance, attributing to the high contact area with the electrolyte and the short solid state diffusion pathway for Li(+) ion/electrons promoting lithium insertion and extraction.

Three-dimensional LiNi 0.5 Mn 0.5 O 2 (3D-LiNi 0.5 Mn 0.5 O 2 ) nanostructures are in situ prepared using cryptomelane-type octahedral molecular sieve manganese dioxide (OMS-2) in the form of dendritic nanostructures as templates. The complete conversion of the OMS-2 precursor to layered α-NaFeO 2 -type LiNi 0.5 Mn 0.5 O 2 and the retention of the 3D dendritic nanostructures have been confirmed by XRD, FE-SEM, TEM, and HR-TEM. The as-synthesized nanostructured positive electrode exhibits a significant improvement in rate performance and cycling reversibility due to its unique nanostructures composed of single-crystalline LiNi 0.5 Mn 0.5 O 2 nanorods. And the influence of the assembly mode of nanosize LiNi 0.5 Mn 0.5 O 2 positive electrode material to its electrochemical performances has been investigated. The battery based on 3D-LiNi 0.5 Mn 0.5 O 2 retains a discharge capacity of 151.6 mAh g −1 (93% of the first discharge capacity) after 50 cycles. A specific discharge capacity of 141.8 mAh g −1 was retained at a rate of 3.2 C, which is about 80% of the capacity at a rate of 0.2 C.

This paper reports an inverted fabrication process for the photoanode of a flexible dye sensitized solar cell (DSSC). This procedure involves assembling a free-standing TiO2 nanowires/nanoparticles hybrid membrane, via high temperature annealing, sputtering an indium tin oxide (ITO) layer onto this membrane, and transferring these onto a polydimethylsiloxane (PDMS) substrate. The inverted procedure prevents thermal decomposition of polymer substrate, whilst enabling effective thermal treatment of the functionalized titanium oxide. The flexible DSSC fabricated in this way has an efficiency of 2.7%, which is comparable with rigid device constructed using similar materials.

Microfluidics-based circulating tumor cell (CTC) isolation is achieved by using gelatin-coated silica microbeads conjugated to CTC-specific antibodies. Bead-binding selectively enlarges target cell size, providing efficient high-purity capture. CTCs captured can be further released non-invasively. This stratagem enables high-performance CTC isolation for subsequent studies.

Highly uniform and transparent polyaniline (PANI) electrodes that can be used as counter electrodes in dye-sensitized solar cells (DSSCs) were prepared by a facile in situ polymerization method. They were used to fabricate a novel bifacially active transparent DSSC, which showed conversion efficiencies of 6.54 and 4.26% corresponding to front- and rear-side illumination, respectively. Meanwhile, the efficiency of the same photoanode employing a Pt counter electrode was 6.69%. Compared to conventional Pt-based DSSCs, the design of the bifacial DSSC fabricated in this work would help to bring down the cost of energy production due to the lower cost of the materials and the higher power-generating efficiency of such devices for their capabilities of utilizing the light from both sides. These promising results highlight the potential application of PANI in cost-effective, transparent DSSCs.

TiO2 sols were synthesized via hydrothermal reaction using a less hydrolysable alkoxide or tetrabutyl titanate as the starting material. Using characterizations of X-ray diffraction, dynamic laser scattering and transmission electron microscopy, particle coarsening dynamics along with the particle dispersion behavior in the sols were studied via changing hydrothermal temperature from 160 °C to 250 °C. It was observed that, pure anatase phase was obtained in the whole examined temperature range. With temperature increasing, the particle size distribution in the sols first narrowed, and then broadened. Mono-dispersed nanocrystallites were obtained at the temperature of 220 °C. Aggregations were formed between the nanocrystallites at other temperatures. The causes of the aggregating behavior were analyzed and found to be different when the temperature was less than or beyond 220 °C. The as-synthesized TiO2 sols were used in fabrication of dye sensitized nanocrystallite solar cell. The cells assembled from temperature of 220 °C came out with the best photo-to-electric energy conversion efficiency, which is ascribed to the improved dispersion of particles in TiO2 sols.

Solvent, dispersant, and surfactant play different roles in forming porous films of dye-sensitized solar cells (DSSCs) when they are added into the paste. We investigate the influence of ethanol, acetylacetone, and Triton-X100 on the photoelectrode of DSSCs with orthogonal array design experiments. Stereoscopic morphologies of photoelectrodes scanned with atomic force microscopy (AFM) show that decreasing the amount of ethanol in TiO2 paste results in forming a more compact structure of the photoelectrode for DSSCs. The TiO2 photoeletrode made with 2.5 g of TiO2 nanoparticle powder dissolved in 20 mL of ethanol presents lower root-mean-square (rms) roughness calculated from AFM, and its corresponding performance in DSSCs shows higher photoelectric conversion efficiency, while the effects of acetylacetone and Triton-X100 on the performance of DSSCs are not very apparent. Optimized photoelectrode dyed with N719 shows increased light absorption. This may result from adsorbing more amount of dye on a larger i...

Counterelectrode plays an important role in dye sensitized solar cells. It helps the regeneration of the redox couples in electrolyte and makes the cell a complete circuit. In order to improve the electrochemical performance of counterelectrode, a strategy of sandblasting has been utilized to pre-treat the surface of glass substrate. Counterelectrodes were fabricated by sputtering Pt/Ti bilayers films onto the treated substrates. Morphological, electrical, electrochemical and optical properties of the counterelectrode were characterized by scanning electronic microscopy, four-probe measurement, electrochemical impedance spectroscopy, cyclic voltammetry and UV–vis reflection spectroscopy, respectively. Effect of the treatment on these properties was evaluated. It was found that counterelectrode made from sandblasted substrates showed increased roughness of surface and sheet resistance, along with the enhanced catalysis efficiency and improved light scattering. The enhanced catalysis efficiency toward reduction of tri-iodide was found to be due to smaller Pt crystallite grown on the sandblasted substrate, since the electrochemical active surface area changed little. And scattering was caused by increased roughness of the substrate. Typical solar cells were assembled with the counterelectrode made of the sandblasted substrates. Effect of the treatment on current–voltage curves and performance parameters of the solar cells was checked and discussed.

We report two improved stability dye-sensitized TiO2 solar cells using poly (ethylene oxide)–poly (vinylidene fluoride) (PEO–PVDF) polymer-blend electrolytes modified with water and ethanol as hydroxyl-rich small-molecule additives. The effect of additive on the thermal property, viscosity, conductivity and the corresponding performance of the dye-sensitized solar cell (DSSC) were studied. After introducing the water and ethanol into the PEO–PVDF polymer-blend electrolytes, the conductivity is improved compared to that of the un-added electrolyte. This is due to the enhanced free ion concentration and ion transport channels in the electrolyte because of the cross-linking ability of these hydroxyl-rich additives. The increased ion concentration can be proved by the enhanced concentration of I− and I3− in the additive-modified electrolytes from UV–vis studies. The increased cross-linking network can be explained by the increased glass transition temperature (Tg) and viscosity of these additive-modified electrolytes from DSC and rheology studies. A more homogeneous morphology of ethanol-modified electrolyte from SEM study is used to further explain the better conductivity and stability of the cells based on these additive-modified electrolytes. From the evaluation of additive effect on the performance of the corresponding DSSC, we find that introducing water and ethanol leads to an increase in short-circuit photocurrent density (Jsc). This is due to the efficient transport of I−/I3− caused by enhanced I−/I3− concentration and increased ion transport channels in the electrolyte by adding additives. The best efficiency of 3.9% is achieved in the cell with ethanol-modified electrolyte.

A PEO/P(VDF-HFP) composite polymer electrolyte was modified by different amounts of NH 2 -end functional silane (3-amonopropyltriethoxysilane, APTS). Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) were carried out to examine the configuration changes of the polymer electrolyte. The newly formed Si–O–Si network and interactions influenced the ionic conductivity of the APTS-modified polymer electrolyte and also enhanced the connection of the polymer electrolyte with the electrodes of the dye sensitized solar cells (DSSCs). The cyclic voltammograms and electrochemical impedance measurements indicated that the APTS deprotonated the TiO 2 photoanode surface and negatively changed the Fermi energy level and the conduction band edge to the vacuum level. This effectively reduced the interface recombination in the DSSC and improved the open circuit voltage. With moderate APTS content (0.1 M) modification, the DSSC exhibited a 58 mV improvement of photovoltage and an improved performance of 5.08% compared with 3.74% of the original DSSC.

This paper deals with the distribution of generated microcrystallites in borate glass irradiated by 120 fs laser pulses at a central wavelength of 800 nm. Raman spectroscopy is used to investigate the distribution of the high and low temperature phases of barium metaborate crystals generated in the borate glass. In combination with a microexplosion model, bond-breaking induced by laser irradiation is served as the origin of the formation of BBO crystals. Depending on the laser fluence and cooling conditions, the distribution mechanisms have been discussed.

Novel architectured LiFePO4 (LFP) that consisted of ordered LFP nanocubes was prepared through a facile hydrothermal method using polyethylene glycol (PEG) as a surfactant. The micro/nanostructured LFP with various morphologies ranging from cube cluster to rugby-like structure was synthesized via controlling the pH values of the precursor. A reasonable assembly process elucidating the formation of the hierarchical structure is also provided based on the experimental results. After a combination of carbon (C) coating and reduced graphene oxide (RGO) wrapping, the obtained LFP/C/RGO composites exhibit enhanced electrochemical performance compared to that of blank LFP synthesized under the same condition. Among as-synthesized cube-cluster-like, dumbbell-like, rod-like, and rugby-like composites, the rugby-like LFP/C/RGO reveal the best electrochemical properties with the discharge specific capacity of ∼150 mA h g(-1) after 100 cycles and a high reversible specific capacity of 152 mA h g(-1) at 0.1 C. The prepared LFP/C/RGO composite can be a promising cathode material for high energy, low cost, and environmentally friendly lithium-ion batteries.

The end-functional silicone coupling agent (dodecyl-trimethoxysilane, DTMS for short) was used to modify the PEO/P(VDF-HFP)/SiO(2) nanocomposite polymer electrolyte (CPE) and the different amounts of DTMS modification effects were studied. The experiments showed the silicone coupling agent with hydrophobic alkyl chains (-C(12)H(25)) chemically engineered on the SiO(2) nanoparticles, and formed a Si-O-Si cross-linked network in the new nanocomposite polymer electrolyte. Proper content of DTMS modified CPE exhibited improved ionic conductivity and the connection with the photoanode and counter electrode. However, much higher content of the DTMS modification changed the conformation of the polymer network and reduced the ionic movement. Compared with the performance (3.84%) of the original DSSC, the DSSC with functional silicone coupling agent modified CPE (DTMS:SiO(2) = 2:1, mol ratio) exhibited improved J(sc) (7.94 mA cm(-2)), V(oc) (0.624 V) and optimal efficiency (5.2%) (measured at AM1.5, light intensity of 58.4 mW cm(-2)). The V(oc) of the silicone coupling agent modified polymer electrolyte DSSC is obviously improved, which is mainly due to that the hydrophobic alkyl chain end groups formed an insulating layer that retarded the electron recombination at the TiO(2) nanoporous photoanode/polymer electrolyte interface. The DTMS:SiO(2) = 2:1 modified CPE type DSSC exhibited a performance of 6.42% at a light intensity of 32.1 mW cm(-2) and 4.94% at 99.2 mW cm(-2).

A quasi-solid-state dye-sensitized solar cell employing a poly(ethylene oxide)-poly(vinylidene fluoride) (PEO-PVDF)/TiO2 gel electrolyte modified by various concentrations of water and ethanol is described. It is shown that the introduction of water and ethanol prevents the crystallization of the polymer matrix, and enhances the free I(-)/I(3)(-) concentration and the networks for ion transportation in the electrolyte, thus leading to an improvement in conductivity. A high energy conversion efficiency of about 5.8% is achieved by controlling the additive concentration in the electrolyte. Optimization of the additive-modified electrolyte performance has been obtained by studying the cross-linking behavior of water and ethanol with Fourier transform infrared (FTIR), differential scanning calorimetry (DSC) and viscosity measurements, and the electrical conduction behavior of the electrolyte with impedance spectra measurements.

A simple and efficient two-step method based on dispersive solid phase extraction (D-SPE) and dispersive liquid–liquid microextraction (DLLME) has been developed for the separation and preconcentration of 15 rare earth elements (REEs) from environmental water and sediment samples, followed by electrothermal vaporization-inductively coupled plasma mass spectrometry (ETV-ICP-MS) detection. With Chelex 100 as the adsorbent of D-SPE, target REEs were firstly extracted and the retained REEs were then desorbed by 0.1 mol L−1 HNO3. After 125 mmol L−1 Tris and 40 mmol L−1 1-phenyl-3-methyl-4-benzoylpyrazolone (PMBP) were added into the above elution solution, target REEs were further preconcentrated into CCl4 by DLLME. The developed dual extraction technique exhibited high enrichment factors (234 to 566-fold) and good anti-interference ability. Various parameters affecting the extraction of target REEs by D-SPE and DLLME were investigated in detail. Under the optimal conditions, the limits of detection (LODs, 3σ) for target REEs were in the range of 0.003–0.073 ng L−1 with the relative standard deviations (CY,La,Ce,Pr,Nd,Gd,Dy = 1.0 ng L−1, CSm,Eu,Tb,Ho,Er,Tm,Yb,Lu = 0.2 ng L−1, n = 7) ranging from 6.7 to 11.5%. The proposed method of D-SPE-DLLME-ETV-ICP-MS was successfully applied to the determination of 15 REEs in water and sediment samples with the recoveries of 78–115% and 75–117% for the spiked water and sediment samples, respectively. To validate the accuracy of the method, a Certified Reference Material of GBW07301a stream sediment was analyzed and the determined values were in good agreement with the certified values.

A fibrous polyaniline (PANI) thin film has been fabricated from prepared PANI nanofiber solution by Marangoni flow. The PANI retained its original fiber morphology after being deposited into films and formed highly interconnected network structures, which leads to an excellent electrochemical catalytic activity. This PANI thin film was applied in dye sensitized solar cell (DSSC) as counter electrode. A power conversion efficiency (PCE) of 3.8% of the DSSC by this PANI counter electrode was obtained without optimization of synthesis conditions, compared with 5.1% PCE by traditional Pt counter electrode. Better performances are attainable by improving the conductivity of PANI with acid doping process to decrease the sheet resistance of this electrode. Facile synthesis process and good performance of these nanofibrous PANI thin films highlight the potential large scale applications for low-cost counter electrode in DSSCs.

Three-dimensional silver-embedded porous silicon (3D Ag@porous silicon) micronparticles were synthesized by a facile and low cost method via a metal-assisted chemical etching process for the first time. The electrode based on this 3D Ag@porous silicon anode material reveals a significant improvement in the electrochemical performance that results from its unique interconnected 3D network structure and the existence of high conductive silver nanoparticles encapsulated in the matrix of porous silicon. The battery based on 3D Ag@porous silicon micronparticles still retains a discharge capacity of 784 mA h g−1 after 50 cycles, which is more than two times larger compared with that of graphite (∼372 mA h g−1). These results suggest that this facile and low cost methodology for preparation of a porous silicon anode can be extended to industrial production.

LiNi0.5Mn0.5O2 nanoarchitectured spheres (NA-LiNi0.5Mn0.5O2) have been synthesized via an in situ conversion route derived from the use of γ-MnO2 hollow nanostructured spheres. The complete conversion of the γ-MnO2 precursor to layered α-NaFeO2-type NA-LiNi0.5Mn0.5O2 has been confirmed by XRD, FE-SEM, TEM, and HR-TEM. This NA-LiNi0.5Mn0.5O2 cathode exhibits a remarkable enhancement of rate performance compared with that of LiNi0.5Mn0.5O2 particles prepared by a conventional solid-state reaction method (SS-LiNi0.5Mn0.5O2). The batteries based on NA-LiNi0.5Mn0.5O2 retain a discharge capacity of 153.5 mA h g−1 (93% of the first discharge capacity) after 75 cycles. A specific discharge capacity of 121.9 mA h g−1 was retained at a rate of 3.2 C, which is about 70% of the capacity at a rate of 0.2 C.

To strengthen the adhesion of platinum layer to counterelectrodes of dye sensitized solar cells, titanium thin film has been utilized as adhesion layer between platinum and substrate [Wei et al., Appl. Phys. Lett. 90, 153122 (2007)]. In our study, platinum/titanium bilayer counterelectrodes were fabricated by magnetron sputtering. The structural, electrical, and electrochemical properties of the bilayer counterelectrode were studied by varying the thickness of both platinum and titanium layers. The influence of both electrochemical active surface and crystallite size on charge transfer resistance of the bilayer counterelectrode was explored. From these evaluations, it was found that the as-prepared titanium layer was almost amorphous, and intermetallic phase was formed between platinum and titanium layers. As expected, sheet resistance of the electrode decreased with the increase in deposition time of both platinum and titanium layers. Metal titanium was found to be inert in the catalyzing reduction in tr...