Search

The scaling up of the intensity of beams of atomic clusters (nanoparticle beams) creates a new route to the fabrication of functional nanostructured materials. A challenge is to present, to the directed beam, high surface areas of the desired support material, for decoration by the clusters at local sub-monolayer densities. Then, the clusters and their properties can be preserved. Here we employ the Matrix Assembly Cluster Source (MACS) to demonstrate and characterise the deposition of lead clusters, with size of order 2 nm, into planar sheets of porous carbon paper, a material employed in electrode fabrication. We find that clusters are deposited to a depth comparable with the pore size of the carbon, ~ 50 μm, giving rise to a metal loading of ~ 0.05 mg cm−2 of carbon paper. The functionality of the nanocomposite film so created is demonstrated by its use as an electrode for the electrochemical generation of oxidising species suitable for water purification. [ABSTRACT FROM AUTHOR]

Using nanostructured materials issued from renewable resources could be the key to the development of good-quality low-cost products that help reduce pollution. Cellulose nanofibrils (CNFs) were obtained by alkaline and bleaching treatments of Amazonian Paricá hardwood sawdust, a waste material from the Brazilian forestry industry. This study evaluated a process consisting in alternating layers of Paricá CNFs and cassava starch to coat standard writing and printing (W&P) papers with a skim-coating method, in which one face of each paper sample is passed over the surface of a suspension containing either CNFs or cassava starch, alternatively. The coated samples were then compared to the uncoated paper in terms of mechanical and surface properties. The mechanical properties of the papers coated with alkaline CNFs showed a declining trend as the number of coating layers increased (from 47 to 31 MPa). The papers coated with starch layers showed improved mechanical performance compared to the samples only coated with alkaline and alkaline bleached CNFs. All the coated samples showed excellent resistance to water degradation. The worst degradation (4%) was observed for the samples coated with a single layer of alkaline CNFs. A significant improvement in surface wettability was observed when gelatinized cassava starch was applied to the paper samples, irrespective of the type of CNFs eventually present on the surface. All in all, these results suggest that using gelatinized cassava starch as an alternating layer between successive CNFs layers on the surface of W&P paper samples may be promising for improving their overall properties. [ABSTRACT FROM AUTHOR]

Persulfate is a potential oxidant in direct liquid fuel cells (DLFCs), and the commercial carbon paper (CP) can directly serve as the cathode due to strong oxidizability of persulfate. However, the poor catalytic activity and low specific surface area of CP limit the electrode performance. Herein, a defect-enriched, pyridine-N-dominated and self-standing carbon paper electrode with abundant carbon nanosheets is successfully prepared by hydrothermal treatment combined with in-situ electrochemical exfoliation. Benefitting from the integrated structure, plentiful defects and high-content pyridine-N dopants of the prepared electrode result in the superior electrocatalytic activity and long-term stability in persulfate reduction reaction. Remarkably, a membraneless DLFC with the prepared electrode as cathode and persulfate as the oxidant acquires prominent cell performance and extremely high open circuit voltage of 2.13 V. The maximum power density of the DLFC achieves 241.0 mW cm−2, far higher than those of the previously reported similar membraneless DLFCs. A three-dimensional computational model for the DLFC is developed, which is help to reveal the importance of improving the reaction kinetics and electrical conductivity for the cathode with persulfate as oxidant. A facile approach for in-situ preparation of highly N-doped CP electrode is provided to yield outstanding cell performance for low-cost DLFCs. [Display omitted] • A facile way to introduce high-content nitrogen on carbon paper is proposed. • Massive defective sites, carbon nanosheets and pyridine-N dopants are introduced. • N doping enhances charge transfer and electrocatalytic activity of the electrode. • Effects of hydrothermal duration and precursor concentration are discussed. • The N-doped cathode yields the outstanding cell performance for low-cost DLFC. [ABSTRACT FROM AUTHOR]

Solid-state supercapacitors with areal capacitance in the order of 100 mF⋅cm−2 are developed on paper substrates, using eco-friendly, low-cost materials and a simple technology. The electrochemically active material used as the electrode is prepared from a stable water-based ink, obtained by doping commercial polypyrrole (PPY) powder with dodecylbenzene sulfonic acid (DBSA), and characterized by optical and electrical measurements, Raman investigation and Atomic Force Microscopy. The PPY:DBSA ink can be directly applied on paper by means of rechargeable water pens, obtaining, after drying, electrically conducting solid state tracks. The PPY:DBSA layers are then interfaced to one another through a polymer gel based on potassium hydroxide and chitosan, acting both as the ion-conducting medium and as the separator. The areal capacitance of the devices developed by following such a simple rule can be improved when the PPY:DBSA ink is applied in combination with other nanostructured carbon material. [ABSTRACT FROM AUTHOR]

Just like disposal of waste papers by indiscriminate dumping, stabilisation of clay soil using cement or by firing has a potential adverse effect on the environment and public health. Thus, the essence of this work was to investigate the feasibility of chemically modifying clay soils using waste papers in order to solve the disposal problems and also develop clay-based composites suitable for building purposes. Hydrothermally calcined waste paper ash nanomaterial (HCWPAN) was prepared from assorted waste papers and used to separately develop composites with white clay matrix (WCC) and yellow clay matrix (YCC) each at 0 %, 10 %, 20 %, 30 %, and 40 % volumetric proportions of replacement. Three representative samples were developed in each case. Apparent porosity, water absorption, bulk density, sorptivity, thermal conductivity, specific heat capacity, volumetric heat capacity, thermal diffusivity, thermal lag, flaking concentration, flexural strength, and compressive strength were investigated for all the samples. For satisfactory performance during service, the optimum content level of the HCWPAN was found to be 10 % in the samples. Though the WCC sample possessed greater compressive strength (4.029 ± 0.002) MPa than the value (2.895 ± 0.002) MPa obtained for the YCC sample at that level, the latter exhibited greater potential for enhancement of thermal comfort as a walling element in buildings. Also, reductions from 8.98 % to 8.00 % and 13.30 % to 12.575 % were observed in water absorption of the resulting WCC and YCC samples, respectively. From the technical–economic viewpoint, the HCWPAN is a promising material for clay soil modification for building purposes. [ABSTRACT FROM AUTHOR]

We report a strategy that tunes the CO2 and proton concentrations near the electrode–electrolyte interface using surfactant modification with various amounts (0.05, 0.8, 1.6, and 3.2 mg) of hexadecyl trimethyl ammonium bromide (CTAB). The positively charged group of CTAB favors CO2 surface diffusion and inhibits excessive proton accumulation on Zn nanosheets on carbon paper. A CO faradaic efficiency of 95.6% and a total ampere density of −13.1 mA cm−2 were obtained over the optimal CTAB-modified Zn electrode at −1.1 V with stability over 12 hours. [ABSTRACT FROM AUTHOR]

Adverse Outcome Pathways (AOPs) have been proposed to facilitate mechanistic understanding of interactions of chemicals/materials with biological systems. Each AOP starts with a molecular initiating event (MIE) and possibly ends with adverse outcome(s) (AOs) via a series of key events (KEs). So far, the interaction of engineered nanomaterials (ENMs) with biomolecules, biomembranes, cells, and biological structures, in general, is not yet fully elucidated. There is also a huge lack of information on which AOPs are ENMs-relevant or -specific, despite numerous published data on toxicological endpoints they trigger, such as oxidative stress and inflammation. We propose to integrate related data and knowledge recently collected. Our approach combines the annotation of nanomaterials and their MIEs with ontology annotation to demonstrate how we can then query AOPs and biological pathway information for these materials. We conclude that a FAIR (Findable, Accessible, Interoperable, Reusable) representation of the ENM-MIE knowledge simplifies integration with other knowledge. Scientific contribution: This study introduces a new database linking nanomaterial stressors to the first known MIE or KE. Second, it presents a reproducible workflow to analyze and summarize this knowledge. Third, this work extends the use of semantic web technologies to the field of nanoinformatics and nanosafety. [ABSTRACT FROM AUTHOR]

We employ dielectric spectroscopy and the complex electric modulus formalism to characterize electrical properties of the Ti0.8O2 nanosheets‒Ag nanoparticles‒cellulose filter paper composites, intended for use as a triboelectric nanogenerator. The addition of these fillers (5–17 atom% Ti and 1–6 atom% Ag) increases both the dielectric permittivity and AC conductivity while typically keeping the low loss tangent. The observed exponent to the frequency-dependent universal power law indicates the three-dimensional (3D) hopping mechanism in the composited films, contrasting with the 1D- or 2D-conduction in the ceramics. The electrical responses are also distinct from those of sole nanosheets, indicating some filler-matrix interactions. Electric modulus analyses indicate that the Ti0.8O2 nanosheets act as a charge generation/reservoir, while the Ag nanoparticles generate long-range conduction paths. The relaxation time increases with the dielectric nanosheets content but decreases with metallic nanoparticle content. In addition, these co-fillers decrease the dielectric heating but increases the refractive index of the films. The simple analyses reported herein could be applied to other composites, providing a better understanding on the role of diverse functional co-fillers. [ABSTRACT FROM AUTHOR]

The document titled "Nanotechnologies and Nanomaterials: Selected Papers from CCMR" provides an overview of the applications and development of nanomaterial technology. It explores various methods of synthesizing nanomaterials and discusses their use in fields such as the Internet of Things, energy conversion, intelligent sensing, and biomimetics. The document also covers specific topics related to nanomaterials, including their synthesis, characterization, and applications in areas such as energy storage, electronics, and catalysis. Researchers and library patrons interested in nanomaterials and their applications will find this collection of articles useful for their research. [Extracted from the article]

Gas diffusion electrodes (GDEs) represent a fundamental element for the development of gaseous electrochemical cells like water electrolysis reactors and fuel cells. Various technologies and materials are employed in order to obtain a conductive, stable and gas permeable structure. Among them, carbon-based structures such as carbon paper are widely used: their composition allows the diffusion of gaseous reagents and products and simultaneously does not permit the flooding of the gas-diffusion structure by aqueous electrolytes. However, the hydrophobicity of this material may represent a drawback to water-based electrode synthesis like galvanic deposition, and various chemical or thermal pretreatments were developed in the last decades. A new kind of pre-treatment based on electrical oxidation of the carbon paper surface is here described and evaluated. The electro-oxidative method allows a rapid and localized pre-treatment of the carbon paper, avoiding the use of highly reactive chemicals or long thermal treatments, reducing treatment wastes, time loss and electrical consumption. Surface wettability of the carbon paper before and after pretreatment was compared by contact angle analysis. Pre-treated and virgin carbon paper were subsequently electroplated from a copper deposition bath and deposition morphologies were compared, in order to establish the effect of the pre-treatment. Electroplated supports were analyzed by scanning electron microscopy (SEM) in order to analyze both micro and nanomorphology of the metallic structure. [ABSTRACT FROM AUTHOR]

Herein, we evaluated the use of paper towel, waxed paper, and Parafilm M® (Heathrow Scientific, Vernon Hills, IL, USA) as alternative substrates for screen-printed sensor manufacturing. Morphological study was performed to evaluate the adhesion of the ink on these uncommon substrates, as well as the morphology of the working electrode. The electrochemical characterization was carried out using ferricyanide/ferrocyanide as redox couple. To enhance the electrochemical properties of the developed sensors, the nanomaterial carbon black was used as nanomodifier. The modification by drop casting of the working electrode surface, using a stable dispersion of carbon black, allows to obtain a sensor with improved electrochemical behavior in terms of peak-to-peak separation, current intensity, and the resistance of charge transfer. The results achieved confirm the possibility of printing the electrode on several cost-effective paper-based materials and the improvement of the electrochemical behavior by using carbon black as sustainable nanomaterial. [ABSTRACT FROM AUTHOR]

Cellulose based nanomaterials have the great potential to be applied to paper as bulk additive or coating material to improve overall final properties, especially in secondary fiber. In the present work, the effect of applying different kinds of cellulose nanofibrils (CNF) to papers obtained from recycled fibers using size press on physical, mechanical and barrier properties was investigated and compared with the sole use of starch as coating material. The coating process of CNF was carried out by the addition of size press grade starch to coating suspension. As a cellulose source, wheat straw was evaluated and CNF was obtained through oxidative and enzymatic pretreatments. Results indicate that starch/CNF suspension improves the overall paper properties. As a result of the deposition of coating suspension contains of 4 % wt. periodate-oxidized CNF onto paper surface, tensile and burst indices of papersheets increased as 52.2 % and 194.4 %. Significant decreases were observed in air permeability as 69.8 %. Compression tests also have been conducted to evaluate papersheets end-use properties. In comparison to the other pretreated CNF, due to is lower viscosity, applying periodate-oxidized CNF as size press significantly increased the mechanical properties of the papers fabricated from the recycled pulps. [ABSTRACT FROM AUTHOR]

Developing high-performance and low-cost electrocatalysts for the hydrogen evolution reaction (HER) favorably promotes large-scale hydrogen production from water. Here, we design a nanocomposite of Co 9 S 8 -Ni 9 S 8 nanodiscs (CNS) in-situ grown from polypyrrole hollow nanospheres (PHS) on carbon paper (CP) via unipolar pulse electrodeposition (UPED) technique as HER catalyst in alkaline media. The lattice structure along with the interlacing nanodiscs-like morphology of the Co 9 S 8 -Ni 9 S 8 mischcrystal is controllable by UPED method. The optimal CNS/PHS/CP electrode obtained with pulse potential of − 0.80 V exhibits favorable catalytic activity with low overpotential (186 mV at 10 mA cm−2), superior stability performance (for 100 h with no current density decay), and high electrochemically active surface area up to 1925 cm2, which should be attributed to the interlacing Co 9 S 8 -Ni 9 S 8 mischcrystal with rich active sites, the ingenious combination with conductive polymer, and the integrated electron-proton conductive network. This work will provide a new sight to design low-cost bimetallic sulfide-based electrocatalysts for high-performance HER in water splitting. [Display omitted] • In-situ growth of Ni 9 S 8 -Co 9 S 8 is controllable by unipolar pulse electrodeposition. • Precise regulation of mischcrystal lattice works on the morphology optimization. • Escape from binder contributes to high conductivity and HER catalytic activity. • Integrated frame, large ECSA and rich active sites lift HER dynamics and stability. • The CNS-0.80 catalyst exhibits low overpotential and superior long-term stability. [ABSTRACT FROM AUTHOR]

Improving the performance of porous nickel-based material used widely in the energy field is necessary. Alloying and increasing the specific surface area are essential approaches. This study used rice paper (Chinese traditional calligraphy and painting paper) as biomass templates to prepare hierarchical porous Ni and Ni-Cu foils (Nip and NiCup) with a thickness of about 60 μm by impregnating and high-temperature reduction process. The Ni3S2/Nip electrodes were prepared by an in situ-grown Ni3S2 nanosheet array on the struts of Nip via a hydrothermal process. Two modification methods using Cu-added alloying and Ni-S nanosheet growing were compared to determine their effects on the microstructure, phase, and performance in methanol oxidation (MOR) and urea oxidation (UOR). The results showed that both alloying effects and morphology control can promote MOR and UOR. Compared to the current density value of Nip at 0.8 V, the values of the preferred Ni10Cup and nanosheet array Ni3S2/Nip increased by 24.5% and 27.3% for methanol oxidation and by 15.4% and 38.4% for urea oxidation, respectively. Adding Cu helped to improve electron transfer and facilitated the transition from Ni2+ to Ni3+. The large specific surface area of Ni3S2 nanosheets provided more active sites for the reaction. Compared to Ni10Cup, Ni3S2/Nip with a lower impedance value exhibits better electrocatalytic performance and stability, achieving peak current densities of 269.7 mA cm−2 (MOR) and 303.9 mA cm−2 (UOR) at 0.8 V, maintaining 91.2% (MOR) and 102.4% (UOR) of the initial peak current density after 2000 cycles. The foil electrodes obtained under both modification strategies can be used as anode material in portable cells, and might also be applied to the oxidation of other small organic molecules. [ABSTRACT FROM AUTHOR]

Due to large sulfur (S) content and simple manufacturing techniques, free‐standing cathodes for lithium‐sulfur (Li−S) batteries are gaining a lot of attention recently. Waste office paper, which is consumed in large quantities annually, was used to make a free‐standing paper‐based carbon (FPC) substrate, which inherited fiber‐like morphology. In addition, reduced graphene oxide (rGO) nanosheets modified FPC (rGO@FPC) host was also prepared by a vacuum filtration method. After S impregnation, the FPC/S and rGO@FPC/S free‐standing cathodes were employed in Li−S batteries. The rGO@FPC/S free‐standing cathode exhibited extremely competitive electrochemical performance, including a reversible discharge capacity of 315 mAh g−1 at 0.5 C after 500 cycles. This is due to the uniform S distribution, which boosts the utilization ratio, and the significant blocking action for polysulfide ions, which prevents the redox shuttle effect. [ABSTRACT FROM AUTHOR]

Transparent and nontransparent exoskeleton wearable heaters are used in automobile and aircraft deicing, oil-pipeline defrosting, smart windows, underwater protection clothing, winter sportswear, bioelectronics, personal healthcare, athletic rehabilitation, and thermotherapy applications. In this study, we introduce Korean traditional Han paper (or Hanji), which comprises eco-friendly cellulose fibers from the mulberry bark, as a substrate for nontransparent wearable heaters. Hanji consists of cellulose fibers and is highly flexible, making it suitable for low-cost roll-to-roll scalable production. Graphene flakes are readily and firmly embedded inside the fibrous structure of Hanji by the catastrophic impact inflicted by supersonic spraying. Additionally, Hanji can withstand temperatures of up to 100 °C before suffering thermal damage. The heater with the thicker graphene layer had the lowest electrical resistance and exhibited the highest heating temperature at a constant voltage level. Graphene flakes are firmly held inside the fibrous structure of Hanji, securing the material's mechanical durability. Additionally, tests at various bending radii were conducted to demonstrate the mechanical strength of the Hanji graphene heater. Graphene flakes deposited on an unyielding alumina substrate withstood temperatures of up to 280 °C, thereby facilitating the use of the substrate in high-temperature applications. Graphene-coated textiles were heated and stretched up to 50%, thus demonstrating the application of such materials in human-body thermotherapy. [ABSTRACT FROM AUTHOR]

The design and preparation of a reduced graphene oxide (rGO) paper electrode with a reinforced concrete structure is an effective strategy to improve the mechanical properties of flexible electrodes. Therefore, PEDOT:PSS is added as a binder, toughening and conductive agent. CNTs, with good mechanical properties, are added to enhance the strength. Fe2O3 nanoparticles are added to increase the energy storage. According to these assumptions, we successfully prepared a flexible hydrophilic paper electrode with rGO nanosheets, PEDOT:PSS, CNTs and Fe2O3 nanoparticles by a constant temperature vacuum drying method. In addition, the assembled symmetrical supercapacitor exhibits a high capacitance of 1924 mF cm−3 at 1 mA cm−3, an excellent energy density of 35.6 W h kg−1 (at 166 W kg−1) and a remarkable cycle stability of 98.2% retention over 10 000 cycles at 1 mA cm−2. [ABSTRACT FROM AUTHOR]

In this research, Bougainvillea glabra paper flower extract was used to quickly synthesize biogenic silver nanoparticles (BAgNPs) utilizing green chemistry. Using the flower extract as a biological reducing agent, silver nanoparticles were generated by the conversion of Ag+ cations to Ag0 ions. Data patterns obtained from physical techniques for characterizing BAgNPs, employing UV-visible, scattering electron microscope (SEM), transmission electron microscope (TEM), dynamic light scattering (DLS), X-ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR), suggested that the nanoparticles have a spherical to oval form with size ranging from 10 to 50 nm. Spectroscopy and microscopic analysis were used to learn more about the antibacterial properties of the biologically produced BAgNPs from Bougainvillea glabra. Further, the potential mechanism of action of nanoparticles was investigated by studying their interactions in vitro with several bacterial strains and mammalian cancer cell systems. Finally, we can conclude that BAgNPs can be functionalized to dramatically inhibit bacterial growth and the growth of cancer cells in culture conditions, suggesting that biologically produced nanomaterials will provide new opportunities for a wide range of biomedical applications in the near future. [ABSTRACT FROM AUTHOR]

Nanotechnology applied to pulp and paper sector enables production of nanostructured papers with excellent strength properties. The addition of lignocellulose nanofibrils (LCNF) to traditional kraft pulps is an attractive alternative for production of improved packaging papers. In relation to cellulose nanofibrils (CNF), LCNF application in unbleached papers has the advantage of eliminating the costs of bleaching chemicals and potential advantages in drainage. One aim of this study was producing and characterizing LCNF from eucalypt (E) and pine (P) unbleached pulps and comparing the results with the traditional CNF. Another aim of the work was evaluating LCNF as an additive for production of kraftliner and sackraft nanostructured packaging papers. LCNF proved to be a viable additive for the production of high-strength nanostructured papers while relying on low energy consumption during the refining process. LCNF addition had positive effects on the mechanical properties of the nanostructured papers produced, resulting in significant increases in strength properties. [ABSTRACT FROM AUTHOR]

Nano-TiO pigments in pure crystallographic anatase and rutile phases have been successfully prepared by hydrothermal at 120°C and hydrolysis methods, respectively. The laboratory-prepared pigments were characterized parallel to two commercial pigments of the same crystal structure. All pigments were applied in paper coating mixtures, and their influence on coated paper properties was systematically investigated. X-ray diffraction investigation showed that the laboratory-prepared pigments using the hydrothermal method at 120°C were pure anatase, whereas hydrolysis method produced pure rutile phase pigment. The application of the prepared nanopigments and the corresponding commercial TiO phases in paper coating revealed that clay/rutile nano-TiO pigments in paper coating mixture decreased coated paper roughness more than blending clay with anatase nano-TiO pigments. Commercial nano-TiO pigments increased porosity of coated paper at both the 30% and 50% addition of nano-TiO pigments to clay, while laboratory-prepared nano-TiO pigments highly decreased it at 30% addition of nano-TiO to clay, compared to clay only. Blending of clay/nano-TiO pigments improved both brightness and opacity of the coated paper where commercial pigments are more effective. Burst, tensile strength, stretching, and TEA were improved in the case of all pigments. The 50% addition of the prepared and commercial nanopigments in conjunction with clay improved the mechanical coated paper properties more than 30% addition (except the cases of stretching and TEA of the commercial pigments). The coated paper samples were offset printed. It was found that blending of clay/nano-TiO pigments improved print density. Commercial nano-TiO pigments improved print gloss more than the laboratory-prepared ones. This result was found consistent with the results of coated paper roughness. [ABSTRACT FROM AUTHOR]

TEMPO‐oxidized nanofibrillated cellulose (ONFC) with charged carboxyl groups is introduced for the efficient exfoliation of two‐dimensional (2D) MoS2/graphene composites. As an effective dispersant agent, ONFC can be easily absorbed between the adjacent layers, so as to prevent the accumulation of the exfoliated nanosheets. With the assistance of charged ONFC, the exfoliated MoS2/graphene is gradually increased in the aqueous dispersions with the elongated sonication time. After dewatering, self‐standing MoS2/Graphene/ONFC/CNTs composite films are rationally constructed using ONFC as flexible fibrous skeleton, and CNTs/graphene as 1D/2D interpenetrating electrical networks. Ultrathin MoS2 nanosheets anchored on the 1D/2D heterogeneous networks is directly acted as an ideal paper‐anode for lithium‐ion batteries (LIBs) without using traditional metallic current collector. The self‐standing flexible electrode materials based on natural cellulose will promote the future green electronics with high flexibility, miniaturization, and increased portability. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We study the bulk pore structure of bioactive paper impregnated with an enzyme, alkaline phosphatase (ALP), retained with a cationic polyacrylamide (CPAM) with synchrotron small-angle x-ray scattering and examine the translational dynamics of water in the porous material using H pulsed field gradient NMR. The aim of this study is to understand the perturbation of enzyme kinetics from the bulk behavior through the localization of the enzyme within the pore structure. We interpret the small-angle x-ray scattering data where the range of length scales examined in the scattering experiment corresponds to the packing of the unitary crystallites, or microfibrils, and aggregates of these cellulosic microfibrils. Pulsed field gradient NMR measurement of HO diffusion in the pores between these aggregates indicates that some of these pores are strongly connected allowing convective mass transport, while others exhibit strongly restricted diffusion. Diffusion is also strongly anisotropic. We conclude that the CPAM retention polymer and the protein coat interior surfaces inside the pores of a particular size and that there is no major modification of the pore structure of paper by the CPAM or the ALP. The transport properties of this porous matrix are discussed in terms of the mechanisms by which sorption of ALP may perturb enzyme kinetics. [ABSTRACT FROM AUTHOR]

Disposable nonenzymatic glucose sensors are constructed by electrodepositing NiPt nanosheet arrays on carbon papers. The obtained NiPt nanosheet arrays are fully examined by various techniques including SEM, TEM, XRD and XPS. The glucose sensing performance of the optimal NiPt-3 nanosheet electrode is studied using cyclic voltammetry and chronoamperometry techniques in alkaline electrolyte (0.1 M NaOH). Compared with the counterpart of Ni electrode, the NiPt-3 nanosheet electrode shows highly improved nonenzymatic glucose sensing performance. The sensors achieve a wider linear detection range between 1 μM-10.8 mM with high sensitivity of 2225.5 μA·mM−1·cm−2. The detection limit at 0.55 V is estimated to be 0.4 μM (S/N = 3). The improved glucose sensing performance of NiPt-3 nanosheets may be due to the sheet-like structure and the incorporation of Pt into the NiPt alloy nanosheets. In addition, the high selectivity and preferable feasibility for serum sample analysis demonstrate that the NiPt-3 nanosheet may be a promising disposable electrode for nonenzymatic glucose sensing measurements. [ABSTRACT FROM AUTHOR]

Copyright of Chemija is the property of Lithuanian Academy of Sciences Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Developing highly efficient electromagnetic interference (EMI) shielding materials with outstanding mechanical properties are urgently desirable for portable device hardware and flexible electronic devices. Herein, a highly conductive and flexible silver nanowires/graphene nanosheets/cellulose (AgNWs/GNSs/cellulose) composite paper with particular three‐layered structures is fabricated via vacuum assisted filtered and coating method. The prepared composites exhibit excellent EMI shielding property due to the unique layered structure. By changing the order of the conductive layers, the overall shielding performance can be further improved. An outstanding EMI shielding effectiveness (SE) of 53.3 dB is achieved with a thickness of only 0.17 mm. The composites show prominent bending resistance, which is proved by 1000 times of repeated bending leading to no obvious changes in structure. Moreover, the prepared composites exhibit excellent mechanical properties. Therefore, it is expected that this work will open up a facile strategy for exploiting materials with excellent EMI shielding properties and mechanical performance. [ABSTRACT FROM AUTHOR]

Low-cost, paper-based platforms are gaining increasing relevance in modern diagnostics and biosensing. Most diagnostic systems using blood samples require blood-plasma separation to reduce complexity and achieve better results. Blood plasma separation is often carried-out by using various membrane based filters. This paper presents a new method for capturing red blood cells on Whatman filter paper with no. 1, 2, 5 and glass fiber discs. All four paper types were subjected to modification with hydrothermally grown zinc oxide nanorods. Growth and morphologies of zinc oxide nanorods were confirmed by SEM, XRD and XPS studies. The blood plasma separation experiments were done by cutting the papers into identical strips with dimension of 5 × 20 mm 2 . 3 μL of blood was mixed with equal volume of antibody solution and pipetted on each strip. The colored antibody solution was used to track the path of antibody, eventually the separated plasma. The dried strips were scanned and the difference in the distance travelled by colored solution of antibodies was measured. From the results, it is clear that all four paper strips covered with nanorods have shown more distance travelled and better separation than their control samples. [ABSTRACT FROM AUTHOR]

Paper is a cheap substrate which is in principle compatible with the process temperature applied in the plasma enhanced chemical vapour deposition (PECVD) and hot wire CVD (HWCVD) of thin film silicon solar cells. The main drawback of paper for this application is the porosity due to its fibre like structure. The feature size (micrometre scale) is larger than the thickness of the applied photovoltaic layers. To overcome this problem, UV curable lacquer was used to planarize the surface. Plain 80 grams printer paper was taken as a substrate and the lacquer smoothens the rough surface of the paper such that a designed nanostructure can be imprinted for light scattering. In this manner single junction amorphous silicon solar cells with a HWCVD deposited intrinsic layer were processed on paper, without any concessions to the process temperature of 200 °C. The cell performance is comparable to that of reference cells grown on stainless steel, proving that solar cells can be deposited on paper substrates without sacrificing performance. PV on paper could be applied as "disposable" power source for gadgets, electronic labelling, remote sensing systems, etc. (Internet of Things). [ABSTRACT FROM AUTHOR]

Nowadays, the goal of carbon peaking and carbon neutrality has become a global consensus, and electrochemical CO2 reduction to provide high-value power fuel is one of the major technical approaches attracting significant research interests and application prospects. However, the inevitable hydrogen evolution reaction in water-based electrolyte systems crowds out the reactive sites of active metals, causing a low CO2 conversion efficiency. In this work, Zn nanosheets were prepared via electrodeposition on the surface of carbon paper and then modified with polytetrafluoroethylene (PTFE) to tune the wetting angle of the electrolyte. A CO faradaic efficiency of 90.2% was achieved for Zn NS-8% PTFE (contact angle: 136.8°) at the electrolytic voltage of −1.0 V vs. RHE along with an overall current density of −7.9 mA cm−2. Experimental results and molecular dynamics simulation revealed that PTFE weakened the aggregation of H2O molecules and was more beneficial for capturing and adsorbing CO2 molecules near the electrode surface. The active sites of hydrogen production were transformed into the reaction center for electrocatalytic CO2 reduction due to the hydrophobicity of the electrode, and the accumulation of the local CO2 concentration accelerated the kinetic activity for electrochemical conversion (CO2 to CO). This strategy of tuning the local environment offers an alternative approach for effective electrode manufacturing in liquid electrolytes. [ABSTRACT FROM AUTHOR]

Electric‐driven conversion of carbon dioxide (CO2) to carbon monoxide (CO) under mild reaction conditions offers a promising approach to mitigate the greenhouse effect and the energy crisis. Surface engineering is believed to be one of the prospective methods for enhancing the electrocatalytic activity of CO2 reduction. Herein, hydroxyl (OH) groups were successfully introduced to cadmium nanosheets to form cadmium and cadmium hydroxide nanocomposites (i. e. Cd/Cd(OH)2 nanosheets) via a facile two‐step method. The as‐prepared Cd/Cd(OH)2/CP (CP indicates carbon paper) electrode displays excellent electrocatalytic activity for CO2 reduction to produce CO. The Faradaic efficiency of CO reaches 98.3 % and the current density achieves 23.8 mA cm−2 at −2.0 V vs. Ag/Ag+ in a CO2‐saturated 30 wt% 1‐butyl‐3‐methylimidazole hexafluorophosphate ([Bmim]PF6)‐65 wt% acetonitrile (CH3CN)‐5 wt% water (H2O) electrolyte. And the CO partial current density can reach up to 71.6 mA cm−2 with the CO Faradaic efficiency of more than 85 % at −2.3 V vs. Ag/Ag+, which stands out against Cd/CP, Cd(OH)2/CP, and Cd/CdO/CP electrodes. The excellent electrocatalytic performance of the Cd/Cd(OH)2/CP electrode can be attributed to its unique structural properties, suitable OH groups, perfect interaction with electrolyte, abundant active sites and fast electron transfer rate. [ABSTRACT FROM AUTHOR]

Nanozymes, enzyme-mimetic nanomaterials that combine features of nanoscale material with the catalytic properties of enzymes, have undergone rapid development in recent years. While enzymes have remained integral to biosensor technologies for the past several decades, the emerging potential of nanozymes to overcome the low stability and high production costs of biological enzymes has turned them into promising biosensor candidates. Nanozymes have already been explored for a myriad of biosensing applications. However, only a small subset of these efforts has resulted in devices and platforms that are potentially suitable for on-site/point-of-care monitoring. To promote efforts in this area, the review first provides a concise overview of different paper-based technologies, their architecture and functionality, in a language conducive to the nanozyme research community. The review, then, critically discusses the progress made in the integration of nanozymes in biosensor platforms for on-site detection of food contaminants, environmental pollutants, and disease biomarkers. The challenges associated with the transition of solution-based nanozyme biosensors to relevant devices and technologies are highlighted, and strategies to overcome those challenges are proposed. We envision that this review could narrow the gap impeding the translation of nanozyme-based biosensor technologies from laboratories to real-world scenarios by encouraging consolidated cross-disciplinary and trans -sectoral efforts. • Nanozyme-based biosensors (NzBS) are of topical interest. • Translation of NzBS to end-users warrants device development. • Integration of NzBS with paper-based devices for POC testing is discussed. • The role of NzBS across the food, environment, and health sectors is reviewed. • Challenges and prospects of NzBS for real-world applications are outlined. [ABSTRACT FROM AUTHOR]

In this study, nanomaterials capable of enzyme-free glucose quantification and colorimetric readout are integrated into a microfluidic paper-based analytical devices (μPADs). Gold nanoparticles (AuNPs) and silver nanoparticles (AgNPs) were utilized as a peroxidase-like nanozyme and a colorimetric probe to achieve glucose monitoring. In this developed device, glucose is oxidized by AuNPs to generate hydrogen peroxide (H 2 O 2), which flows in the paper microchannels toward detection zones. H 2 O 2 then etches the immobilized AgNPs to induce a color change. The intensity of color change is easily monitored using a smartphone application. Following method optimization, we obtained a linear range from 0.50 to 10.0 mmol L−1 (R2 = 0.9921) and a detection limit (LOD) of 340.0 μmol L−1. This falls in the clinically relevant range for glucose monitoring and diabetes diagnosis in humans. In addition, the total analysis time is just 20 min, which is significantly less than the same experiment performed in the solution phase. Also, our method is markedly selective; other substrates do not interfere. The recovery test in human control samples was in the range of 98.47–102.34% and the highest relative standard deviation (RSD) was 3.58%. The enzyme-free approach for glucose sensing is highly desirable for diabetes diagnosis as it replaces the more expensive enzyme with cheaper nanomaterials. Furthermore, since nanomaterials are more environmentally stable compared to enzymes, it has the potential for widespread deployment as point-of-care diagnostics (POC) in resource-limited settings. [Display omitted] • We report the application of nanomaterials-based μPADs for glucose monitoring with an enzyme-free. • The sensor was constructed by immobilizing nanomaterials on a paper substrate. • The sensor is faster than the same assay in the solution phase. • The analytical merit is suitable for glucose detection in the clinical relevance. [ABSTRACT FROM AUTHOR]

Starch and derivatives thereof have proven their usefulness in paper coating processes. Among these derivatives, cationic starch has been widely used in the paper industry as a flocculation, dispersion and ink fixing agent. In another context, nanoscale cellulosic materials have been shown to improve the strength, retention of fillers, the barrier properties of packaging paper products, and printing qualities. This review summarizes the recent studies on the general components used in paper coating, describes the conventional and alternative synthetic processes of cationic starches and nanocellulose, and deals with their current and potential applications in papermaking, focusing primarily on surface treatments. Moreover, environmental applications have been considered to expand the understanding and usefulness of these materials. Further research on modified polysaccharides is encouraged to replace, in a feasible way, petro-based components of coating formulations, and to provide paper surfaces with new properties. [ABSTRACT FROM AUTHOR]

[Display omitted] • PEDOT:PSS and Borophene nanosheets modified conducting paper. • Cost efficient and flexible biosensor for protein biomarker detection. • Environment friendly biosensing platform with smoke free degradation. • Ultralow LOD (0.49 ng ml−1) and wider LDR (1 ng ml−1 - 60 µg ml−1) for swine flu detection. Here, we report results of the studies related to the fabrication of nanomaterial modified paper [Whatman paper modified with poly(3,4-ethylenedioxythiophene):poly(4-styrene sulfonate) (PEDOT:PSS) and Borophene nanosheets] based biosensor for proteinaceous Serum Amyloid A (SAA) biomarker detection. For the fabrication of stable and cost-efficient nanomaterial modified conducting paper, we used simple dip coating method followed by solvent treatment. The incorporation of Borophene nanosheets onto the conducting paper resulted in enhance electrochemical performance, flexibility and signal stability. The flexibility of fabricated electrode is validated via bending and folding studies; it continues to maintain conductivity even after being folded 40 times. Furthermore, this paper sensor may be quickly and properly disposed of by simple burning method without emitting smoke. It was also observed that no any harmful/heavy element was present after disposal of the paper sensor. During fabrication of paper based sensor, anti-SAA was physically immobilized and further bovine serum albumin (BSA) was used to block the non-specific binding sites. To examine structural and morphological features of the synthesized material and the fabricated paper electrodes; X-ray diffraction, transmission electron microscopy, scanning electron microscopy, contact angle, and Fourier-transform infrared spectroscopy were used. The fabricated immunoelectrode (BSA/anti-SAA/Borophene/CP) is highly efficient to detect SAA with ultralow limit of detection of 0.49 ng mL−1, wider linear detection range in between 1 ng mL−1 - 60 µg mL−1 and high durability of 42 days. Finally, SAA protein in spiked serum samples was analyzed using the fabricated immunosensor, and the obtained results show good correlation with the standard SAA protein samples. [ABSTRACT FROM AUTHOR]

This work describes the development and evaluation of a new electrochemical platform based on the sustainable generation of gold-nanoparticles on paper-based gold-sputtered electrodes. The disposable porous paper electrode is combined with screen-printed electrodes for ensuring a precise electrogeneration of nanoparticles and also for the evaluation of these simple, versatile and low-cost microfluidic devices. Two types of chromatographic paper with different thicknesses have been evaluated. Paper gold working electrodes modified with gold nanoparticles were characterized by scanning electron microscopy and cyclic voltammetry using potassium ferrocyanide as a common redox probe, showing an improved electrochemical performance when compared to bare gold electrodes. The platform has been applied to the non-enzymatic determination of glucose, molecule of enormous interest. The porous gold structure made by sputtering on paper, modified with electrogenerated nanoparticles allowed precise and accurate determination of the analyte in beverages at low potential. [ABSTRACT FROM AUTHOR]

Nanoalloy shows significant advantages and broad application prospects in chemical catalysis, due to the possessed high specific surface energy and abundant active sites can greatly promote their catalytic performance. In this work, morphology-controlled Cu-Sn alloy nanosheet arrays supported on carbon fiber paper (CP) substrate (Cu-Sn/CP) have been developed by a facile one-step electrodeposition technique at room temperature for the first time. Benefiting from the large active surface area, considerable ion transport channels and strong synergistic catalytic effect between Cu and Sn, the as-prepared Cu-Sn/CP served as a self-supported electrode for efficient nonenzymatic glucose sensing. Under optimized conditions, Cu-Sn/CP electrode offers wide linear ranges of 0.0005–2.0 mM and 2.0–10.0 mM, respectively. The detection limit is as low as 0.061 μM (S/N = 3). Cu-Sn/CP electrode also exhibited excellent selectivity and stability. Additionally, the proposed sensor is proven to be suitable for the detection of glucose in human serum samples. [Display omitted] • Morphology-controlled Cu-Sn/CP was first synthesized by a cost-efficient one step electrodeposition strategy. • Non-precious Cu-Sn alloy nanosheets were used for the electrocatalytic oxidation of glucose for the first time. • Cu-Sn/CP showed high electrocatalytic activity for glucose oxidation with wide linear range and low detection limit. • The as-proposed biosensor exhibited excellent anti-interference ability and stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • N-doped 1T-2H MoSe 2 /N doped carbon paper was fabricated by a low-temperature nitrogen plasma strategy. • N doping along with 1T phase into the 2H-MoSe 2 can expose more active edge sites and improve electrical conductivity. • N-MoSe 2 /NCP-30 only needs an overpotential of 274 mV to reach −200 mA cm−2 with Tafel slope of 54.7 mV dec-1. Molybdenum selenide (MoSe 2) is considered to be a promising catalyst for seawater hydrogen evolution, but its catalytic activity falls far short of requirements due to its inert surface. Here, self-supported N-doped 1T@2H-MoSe 2 /N doped carbon paper (N-MoSe 2 /NCP) was fabricated by a novel low-temperature nitrogen plasma strategy. In alkaline simulated seawater, the optimized N-MoSe 2 /NCP-30 only requires an overpotential of 274 mV to reach −200 mA cm−2 with Tafel slope of 54.7 mV dec-1, and exhibits stability over 24 h. This work proposes that the introduction of 1 T phase and N dopant into 2H-MoSe 2 using low-temperature plasma strategy can significantly facilitate the exposure of abundant active edge sites and boost the conductivity of MoSe 2. [ABSTRACT FROM AUTHOR]

In this paper, we present a facile and cost-effective method to obtain superhydrophobic filter paper and demonstrate its application for efficient water/oil separation. By coupling structurally distinct organosilane precursors (e.g., octadecyltrichlorosilane and methyltrichlorosilane) to paper fibers under controlled reaction conditions, we have formulated a simple, inexpensive, and efficient protocol to achieve a desirable superhydrophobic and superoleophilic surface on conventional filter paper. The silanized superhydrophobic filter paper showed nanostructured morphology and demonstrated great separation efficiency (up to 99.4%) for water/oil mixtures. The modified filter paper is stable in both aqueous solutions and organic solvents, and can be reused multiple times. The present study shows that our newly developed binary silanization is a promising method of modifying cellulose-based materials for practical applications, in particular the treatment of industrial waste water and ecosystem recovery. [ABSTRACT FROM AUTHOR]

Surprisingly the strength of wet paper is still poorly understood. Here we show that the traditional explanation of the strength of wet paper is incorrect. Observations that the capillary force in fiber crossings in wet paper approaches zero as the water is evaporated show that they are not responsible for the strength of wet paper. Instead we present evidence that fiber entanglements and friction are the cause. Like paper, films made of nanotubes, nanorods, nanofibers or nanoribbons also consist of randomly oriented fibers, and this field may well benefit from an increased knowledge of paper properties. [ABSTRACT FROM AUTHOR]

Abstract: Platinum–ruthenium (Pt–Ru) nanoparticles were successfully deposited, for the first time, on the surface of SnO2 nanowires grown directly on carbon paper (Pt–Ru/SnO2 NWs/carbon paper) by potentiostatic electrodeposition method. The resultant Pt–Ru/SnO2 NWs/carbon paper composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The electrocatalytic activities of these composite electrodes for methanol oxidation were investigated and higher mass and specific activities in methanol oxidation were exhibited as compared to Pt–Ru catalysts deposited on glassy carbon electrode. [Copyright &y& Elsevier]

Abstract: The large surface area and rich functional groups of a 2D nanostructure, sulfonated graphenal polymer (SGP), provide a new strategy to assist the dispersion of carbon nanotubes (CNTs), far better than the dispersing ability of graphene oxide and sodium dodecyl benzene sulfonate. The efficient codispersion of CNTs and SGP facilitate the fabrication of composite buckypapers with wide‐range tunable fractions of CNT, SGP, and polymer, like poly(vinyl alcohol) (PVA), making it possible to search out the most optimal structure in the fraction space of the constituents. The globally strongest buckypaper is obtained at a CNT:SGP:PVA mass ratio of 7:3:10. Owing to the super hydrophilicity of SGP, and the hydrophilic characteristics of PVA as well, the composite structure can be reassembled with the aid of water, resulting in easy removal of creases and efficient cut heal/repair to broken papers. The healed papers can exhibit about 80% recovery of the tensile strength. Furthermore, just by mechanical stirring, the composite buckypaper can be redissolved in water for a totally green recycling reuse. [ABSTRACT FROM AUTHOR]

Abstract: Paper, one of the oldest materials for storage and exchange of human's information, has been reinvented as a building component of electronic and optoelectronic devices over the past decades with successful demonstration of paper‐based or paper‐using devices. These recent achievements can meet the demand for lightweight, cost‐effective, and/or flexible electronic and optoelectronic devices with advanced functionality and reduced manufacturing costs. This article provides a review of electronic and optoelectronic devices relying on or making use of the unique properties achievable with paper‐based materials. Basic scientific/technical principles, quantitative comparisons of material, electronic and/or optical properties, and benefits for each paper‐based application are given. Application‐specific research challenges, future design considerations, and development directions are also discussed. [ABSTRACT FROM AUTHOR]

The high cost of regular diagnostic kits severely impeded its uses for routine clinical assay and fieldworks. A cost-effective chromatography paper is chemically modified with Ag nanostructures using the simple electroless silver deposition, producing a scalable and disposable substrate for surface-enhanced Raman spectroscopy, as well as a large scale of catalytic active sites over many chemical reactions. Synergetic measurement including surface-enhanced Raman spectroscopy and laser desorption ionization-mass spectrometry is performed on Ag decorated filter paper using a thiol containing compound as indicator, allowing for the acquisition of spatially correlated spectroscopy in the tandem mode. In addition, hydrophilic porous cellulose network that contains a certain amount of liquid naturally served as a chemical reactor for molecular transport and reaction. Positive results from catalytic reaction on metallized paper convincingly demonstrated that total microanalysis system on paper (μ-TASoP), as a compelling alternative would find a wide breadth of applications in developing disposable medical devices and customary laboratory assays. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract Paper based biosensor devices have the benefit of easy-use, low-cost and environmental friendly for point-of-care diagnostic application. In this research, we report a novel form of paper based biosensor with hierarchical assembled nanomaterials and MOF enhanced bio-probes for the simultaneous detection of microRNA-141 (miR-141) and microRNA-21 (miR-21) which have the potential for early cancer detection. The combination of multi-dimensional nanomaterial allows low impedance and high sensing area on typical poorly defined paper substrate. MOF conjugated bio-probe, methylene blue (MB) and ferrocene (Fc) with distinguishable electrochemical signal, further contributed to the high selectivity and sensitivity. Simultaneously detection of miR-141 and miR-21 with a detection limit of 0.1 fM was demonstrated under optimal conditions. All these features enable accurately target detection in serum samples. Therefore, this strategy is of promising as an inexpensive, easy access diagnosis platform for cancers by means of simultaneously detection of a variety of miRNA biomarkers. Highlights • MoS 2 /AuNPs/AgNW paper-based electrode was used as sensing platform. • Hairpin DNA nanostructures-based biosensor was developed with the detection limit of 0.1 fM. • PtCuMOFs/DNA was used for simultaneous detection miRNA and signal amplification. • The DNA biosensor could be utilized in real serum sample analysis. [ABSTRACT FROM AUTHOR]

• 1T-MoS 2 was applied as a flexible and functional "spacer" to hybridize with Ti 3 C 2 T X MXene, forming flexible capacitive freestanding films. • The insertion of electrically neutral pseudocapacitive could mitigate the restacking of Ti 3 C 2 T X MXene layers and improves the capacity of the composite paper. • The supercapacitor fabricated with acidic gel electrolyte and composite electrode with randomly stacked MXene and 1T-MoS 2 in a mass ratio of 6:1 demonstrated optimal performance. In the case of increasing shortage of non-renewable resources, developing high-efficiency and high-capacity energy storage devices is critical. Supercapacitors have the potential of high-efficiency and high-capacity. MXene and 1T-MoS 2 are two kinds of high performance pseudocapacitive materials. However, the stacking and aggregation of MXene nanosheets greatly reduce its capacity. The poor conductivity of 1T-MoS 2 also limits the full expression of its excellent pseudocapacitive performance. A flexible MXene/1T-MoS 2 composite paper electrode is designed and prepared in this work where the restacking of MXene can be relieved and the whole electrode maintains the conductivity. The interior stacking structure of MXene and 1T-MoS 2 in the composite paper, as well as the gel electrolyte type are explored. The device constructed with the electrode composed of randomly stacked MXene and 1T-MoS 2 (mass ratio 6:1) and acidic electrolyte (PVA/H 2 SO 4 gel electrolyte) demonstrates the optimal performance. The specific areal and volumetric capacitances reach 561.2 mF cm−2 and 1268.17 F cm−3 at the current density of 0.8 mA cm−2 respectively, outperforming most of the previously reported values for MXene based supercapacitors tested in gel electrolyte. The supercapacitor has excellent deformation durability and long cycle stability, demonstrating promising prospect in future flexible electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: The texture of the C–S–H gels formed in ternary cement blends containing thermally activated paper sludge (APS), fly ash (FA) from coal combustion and Ordinary Portland Cement (OPC) was studied by means of the specific surface area (SSA) and pore-size distribution (PSD), which were measured by the sorption isotherms of nitrogen gas and the BET method. Two differentiated zones in the PSD of the C–S–H gel at ∼10–20nm and ∼5nm were observed. The proportion of such zones depends on the age of hydration and amount of OPC replacement. The incorporation of the additions (APS and FA) clearly revealed an increase in both porosity and SSA. This effect decreased with the progress of hydration together with a refinement of the nano-porous structure of C–S–H. High correlations were found among these nanostructure characteristics of the C–S–H gel and mechanical strengths. [Copyright &y& Elsevier]

Titanium dioxide is cheap, non-toxic, exhibits a high mechanical resistance, very stable in acidic and oxidative environments is being studied as alternative to carbon as catalyst support in low-temperature fuel cells. Herein, via pulsed laser deposition, various morphologies of TiO 2 thin films are synthesized at room temperature onto conductive microfibrous carbon paper substrate, which is the type of substrate, employed in energy storage and conversion devices. TiO 2 films deposited under vacuum and in the presence of mild pressure of oxygen are very smooth and dense. Instead, TiO 2 films deposited in the presence of helium atmosphere are of porous structures and vertically aligned. An increase in the helium pressure leads to the formation of forest-like vertically aligned nanostructures. Micro-Raman spectroscopy reveals that the films are amorphous and of rutile phase. X-ray photoelectron spectroscopy shows that Ti is in fully oxidized state of Ti 4+ . The electrocatalytic supporting properties to Pt are investigated in H 2 SO 4 and O 2 -saturated H 2 SO 4 solution. It is found that regardless of the film morphology, all the synthesized TiO 2 films dramatically increase the electroactive surface area of Pt and enhance its electroactivity towards oxygen reduction reaction as compared with bare Pt electrode. [ABSTRACT FROM AUTHOR]

Nile red has been an alternative reagent for detecting latent fingerprints on wetted substrates. However, the presence of methanol in nile red solution could make injury to handlers and destroy the traces on surfaces, such as texts on thermal papers. A novel small particle reagent formulation constituting of mesoporous silica nanoparticles (MSNs) based on nile red was prepared to overcome the problem. Compared with the conventional reagents Oil Red O or nile red solution, the nile red‐loaded MSNs are highly selective to lipid residues of fingerprints and showed a greater ability to develop clear, sharp, and detailed fingerprints on thermal papers after these were immersed in water. In addition, it can retain texts on the thermal papers well and use only water as a solvent. These suggested that nile red‐loaded MSNs are a safe, efficient, and convenient method to develop latent fingerprints on wide range of substrates of forensic importance. [ABSTRACT FROM AUTHOR]

Abstract Paper-based immunosensors are regarded as attractive analytical tools for performing point-of-care and in-field assays in medical diagnostics, environmental monitoring and food safety control. In this review, we provide a general overview of the types and applied detection techniques of paper-based immunosensors published in recent years and analyse the current trends in these two aspects. The first section introduces the background of paper-based immunosensors and critically discusses the necessity and distinct features of existing paper-based immunosensors. The second section summarizes the types of current paper-based immunosensors, including paper-based lateral-flow assays (LFAs), microfluidic paper-based analytical devices (μPADs) and some other device types. In the third section, we describe various detection techniques currently applied in paper-based immunosensors, covering optical, electrochemical and some multiple detection techniques. Finally, current trends and future perspectives are also discussed. We hope this review will be a helpful reference for readers of various fields. Highlights • The application value of paper-based immunosensors is emphasized. • Current paper-based immunosensors are outlined according to two aspects. • Representative examples of paper-based immunosensors are elaborated. • The current trends and prospect of paper-based immunosensors are discussed. [ABSTRACT FROM AUTHOR]