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In this study, a piece of filter paper with good flexibility and hygroscopicity was used to support catalysts after a pencil drawing process. A layer of thin Ni film was deposited on the surface of the conductive graphite layer using an electrochemical method at a negative potential. Pd nanoparticles with high electrocatalytic activity for NaBH4 oxidation were introduced by immersing the Ni film-graphite-filter paper (NGF) in PdCl2 solution to obtain a Pd-NGF (PNGF) electrode. The morphology and phase structure of PNGF were characterized using scanning electron microscopy (SEM) equipped with an energy dispersive X-ray spectrometer (EDS), transmission electron microscopy (TEM) and an X-ray diffractometer (XRD). The PNGF electrode was used as the anode in direct borohydride fuel cells (DBFCs), and the electrochemical properties for NaBH4 oxidation were determined by cyclic voltammetry (CV), chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS). The oxidation current density reaches 550 mA cm−2 at −0.4 V when the electrolyte contains 2 mol dm−3 NaOH and 0.10 mol dm−3 NaBH4. [ABSTRACT FROM AUTHOR]

The catalytic combustion of diesel soot is addressed with flexible and structured "paper catalysts". Two different series of catalysts were prepared either by drip impregnation or by a spray method to deposit a mixture of Co, Ba, and K or a mixture of Co and Ce onto SiO2-Al2O3 ceramic paper matrixes. In every case, CeO2 nanoparticles were added to bind the ceramic fibers. SEM images showed that the impregnation method generated catalytic particles concentrated as large chunks (> 10 μm), mainly at ceramic fiber crossings, whereas the spray method produced smaller catalytic particles (< 1 μm) well distributed throughout the ceramic paper. Besides, Co-Ba-K particles appeared better dispersed on the surface of ceramic fibers than Co-Ce due to the presence of K. Additionally, FTIR spectra showed the formation of O22− and O2− species associated with CeO2 (binder) on the samples containing potassium which gave the Co-Ba-K-ceramic paper good catalytic properties, thus making the Co-Ba-K drop impregnated the best catalyst both considering activity and stability. Successive temperature programmed oxidation (TPO) runs up to 700 °C caused the formation of cobalt silicates in the catalytic ceramic paper prepared by the spray method, as indicated by TPR. The formation of these species was probably favored by the smaller size of cobalt particulates and their higher dispersion in the catalysts prepared by the spray method. This provoked the partial loss of the redox properties of Co3O4. TPR experiments also indicated the formation of BaCoO3 in Ba-containing ceramic paper, which could help in maintaining the catalyst activity after several TPO runs through the capacity of this mixed perovskite-type oxide to trap and release NOx. [ABSTRACT FROM AUTHOR]

Abstract: In situ grown carbon nanotubes (CNTs) on carbon paper as an integrated gas diffusion layer (GDL) and catalyst layer (CL) were developed for proton exchange membrane fuel cell (PEMFC) applications. The effect of their structure and morphology on cell performance was investigated under real PEMFC conditions. The in situ grown CNT layers on carbon paper showed a tunable structure under different growth processes. Scanning electron microscopy (SEM) and Brunauer–Emmett–Teller (BET) demonstrated that the CNT layers are able to provide extremely high surface area and porosity to serve as both the GDL and the CL simultaneously. This in situ grown CNT support layer can provide enhanced Pt utilization compared with the carbon black and free-standing CNT support layers. An optimum maximum power density of 670mWcm−2 was obtained from the CNT layer grown under 20cm3 min−1 C2H4 flow with 0.04mgcm−2 Pt sputter-deposited at the cathode. Furthermore, electrochemical impedance spectroscopy (EIS) results confirmed that the in situ grown CNT layer can provide both enhanced charge transfer and mass transport properties for the Pt/CNT-based electrode as an integrated GDL and CL, in comparison with previously reported Pt/CNT-based electrodes with a VXC72R-based GDL and a Pt/CNT-based CL. Therefore, this in situ grown CNT layer shows a great potential for the improvement of electrode structure and configuration for PEMFC applications. [Copyright &y& Elsevier]

Abstract: Vertically aligned carbon nanotubes (VACNTs) grown on carbon paper were obtained by the spray pyrolysis method and highly dispersed Pd nanoparticles were deposited on VACNTs by the wet chemical method. For comparison, the entangled carbon nanotubes (ECNTs) and Vulcan XC-72 based electrodes were fabricated by brush painting the corresponding Pd/ECNTs and Pd/XC-72 catalysts on carbon paper, respectively. Compared with Pd deposition on the entangled carbon nanotubes (ECNTs) and Vulcan XC-72 electrodes, the VACNTs electrode exhibited higher activity for formic acid oxidation, which is mainly due to the three-dimensional structure and better conductive paths in the VACNTs electrode, as well as higher Pd utilization. [Copyright &y& Elsevier]

It is a great challenge to synthesize efficient electrocatalysts for overall water splitting, especially non‐noble metal catalysts. Herein, one‐dimensional polycrystalline nanoneedles composed of CoO−Co9S8 nano heterostructures, in situ grown on carbon fiber paper are prepared for efficient overall water electrolysis. Due to strong electronic coupling, charge densities of Co2+/Co3+ in Co9S8 and Co2+ in CoO are favorably modified at the interface of CoO and Co9S8, resulting in optimized reaction intermediates absorption and greatly enhanced bifunctional HER/OER activities. CoO−Co9S8/CFP delivers a current density of 10 mA cm−2 in alkaline electrolyte at overpotentials of 184 mV and 270 mV for HER and OER, respectively. When used as electrocatalyst for overall water splitting, it needs a low cell potential of 1.66 V to realize water electrolysis at 10 mA cm−2. This work provides a new strategy to tune the electronic structures of transitional metal active sites via constructing nano heterostructures for efficient water electrolysis. [ABSTRACT FROM AUTHOR]

In this study, sludge-derived Fenton-like catalysts, namely potentially low cost, were successfully synthesized through a unique and original method, which was used to oxidative degradate Rhodamine B (RhB) as heterogeneous Fenton-like Fe/C catalysts. Two types of sludge sources were used as sludge-derived support carbon: paper mill sludge and municipal wastewater treatment sludge. This unique preparation method converted pyrolyzed sludge into a porous carbon-based carrier material by chemical activation and then used an iron loading impregnation method to synthesize the Fenton-like Fe/C catalyst. The prepared two types of catalysts including paper mill sludge-derived char-supported iron catalyst and municipal sewage sludge-derived char-supported iron catalyst were characterized in terms of Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy and N2-adsorption/desorption. Compared with sludge-derived Fe/C catalyst without activation, both the PMSC-Fe and the MSSC-Fe catalyst exhibited much better catalytic performance in degrading RhB. Both PMSC-Fe and MSSC-Fe exhibited excellent catalytic stability and almost seldom Fe-ion leaching. A correlation could be found between surface area and RhB degradation, suggesting that surface area of the catalyst is an important factor for the catalytic performance. Two different sources of sludge also showed discrepancy in catalytic performance of RhB degradation, which is perhaps due to the different properties of the initial sewage sludge. The catalyst of PMSC-Fe and MSSC-Fe both has an excellent long-term stability. Possible degradation mechanism of RhB induced by sludge-derived Fe-C/H2O2 system is proposed. [ABSTRACT FROM AUTHOR]

The Fe-N-C nanofibers (NFs) exhibit excellent electro-catalytic activity for oxygen reduction reaction (ORR), which is essential for energy conversion system. Compared with the traditional ink-based electrode, we synthesized the structured Fe-N-C ANFs/CP (activated NFs derived from polypyrrole(PPy) doped with iron atoms in situ grown on carbon paper) by electrochemical polymerization. Herein, we investigate the effect of the iron concentration on the electro-catalytic activity for ORR, revealing that the as-prepared 0.05-Fe-N-C ANFs exhibit superior electro-catalytic activity than 0.01-Fe-N-C ANFs, 0.03-Fe-N-C ANFs as well as 0.10-Fe-N-C ANFs and excellent durability in alkaline solution. It is shown that the better electro-catalytic activity of 0.05-Fe-N-C ANFs for ORR could be ascribing to the fluffy fibrous structure, higher Fe-Nx concentration, and well-dispersed catalytic active sites. [ABSTRACT FROM AUTHOR]

Translating to the Community (T2C) is a social biorepository designed to advance new diagnostic tools and realign community-clinical processes, with the aim to mitigate the short- and long-term impacts of fetal alcohol spectrum disorder (FASD) as well as prenatal alcohol exposure and its co-morbidities and behaviors. In this paper, we describe the evolution of this repository as a new translational partnership to advance a precision-medicine approach to FASD. Key to its evolution was a partnership between academic researchers, Indigenous communities, families, and a regional diagnostic clinic. We further describe the rationale for social biobanking, the type of banking, ethical engagement of families, communities, and clinics, their roles in repository design, governance, translation, and research activities, types of data collected from families, and how the study data are managed, reported, and accessed. The repository design includes biological samples, social-contextual health-survey data, and clinical data (which are linkable to administrative data) from community and clinical cohorts of diagnosed children, children prenatally exposed but not diagnosed, children suspected to have had a prenatal exposure, and related siblings, biological parents, and unrelated children and their parents. From these cohorts and families, potential studies drawing on this data will shed light on various risk factors, social and biological pathways, and service utilization issues, with the aim to implement primary and secondary prevention and intervention strategies. [ABSTRACT FROM AUTHOR]

Fe, N co-doped carbon electrocatalyst is one of the most attractive alternatives to Pt/C catalysts due to its high catalytic activity, excellent stability and low cost. However, obtaining stable and efficient Fe, N co-doped carbon oxygen reduction reaction (ORR) catalysts based on simple processes is still a challenge. Herein, Fe, N co-doped porous carbon (Fe–N–C) with an open macroporous frame structure is prepared by using inorganic molten salts (FeCl3·6H2O and ZnCl2) and ethylenediaminetetraacetic acid as the template and nitrogen-containing carbon precursor, respectively. The open pore structure of the Fe–N–C material precisely tailored with the inorganic molten salt template exhibits high specific surface area (676.5 m2 g−1) and appropriate pore size, which can promote oxygen adsorption and expand the oxygen reduction interface, resulting in the acceleration of the electron/charge transfer processes and an improved electrocatalytic performance. The optimized Fe3–N–C-800 electrocatalyst exhibits good catalytic activity for ORR, such as high onset potential of 0.998 V and half wave potential of 0.84 V in alkaline media, as well as high stability and methanol tolerance. Furthermore, a novel Zn–air battery assembled with carbon paper containing Fe3–N–C-800 electrocatalyst as air cathode shows high open-circuit voltage (1.485 V), high specific capacity (870 mA h g−1 at 10 mA cm−2), excellent reversibility and stability. The proposed synthetic strategy provides new opportunities to design and construct carbon frame materials with the desired open macroporous structure to improve their electrocatalytic performance. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction provides a potential means for synthesizing value-added chemicals over the near equilibrium potential regime, i.e., formate production on Pd-based catalysts. However, the activity of Pd catalysts has been largely plagued by the potential-depended deactivation pathways (e.g., α-PdH to β-PdH phase transition, CO poisoning), limiting the formate production to a narrow potential window of 0 V to -0.25 V vs. reversible hydrogen electrode (RHE). Herein, we discovered that the Pd surface capped with polyvinylpyrrolidone (PVP) ligand exhibits effective resistance to the potential-depended deactivations and can catalyze formate production at a much extended potential window (beyond -0.7 V vs. RHE) with significantly improved activity (~14-times enhancement at -0.4 V vs. RHE) compared to that of the pristine Pd surface. Combined results from physical and electrochemical characterizations, kinetic analysis, and first-principle simulations suggest that the PVP capping ligand can effectively stabilize the high-valence-state Pd species (Pdδ+) resulted from the catalyst synthesis and pretreatments, and these Pdβ+ species are responsible for the inhibited phase transition from α-PdH to α-PdH, and the suppression of CO and H2 formation. The present study confers a desired catalyst design principle, introducing positive charges into Pd-based electrocatalyst to enable efficient and stable CO2 to formate conversion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Immobilization of CuO on paper matrices by an ultrafast (5 min) microwave method. • CuO immobilized paper catalyzes the conversion of CO 2 into cyclic carbonates. • Excellent recyclability of the catalyst (98 % efficiency even after 7 cycles). • Environmental catalyst catalyzes notorious CO 2 to products of industrial importance. Paper matrices immobilized with CuO nanoflakes (width 50−100 nm and length upto 200 nm) by an ultrafast (5 min) microwave assisted method have been used as catalyst for the conversion of CO 2 and epoxides into cyclic carbonates with almost 100 % yield in 20 h at a comparatively low CO 2 pressure of 4 bar. Additionally, some amount of polycarbonate is also formed. The moderate TON of 121 and excellent recyclability performance (98 % retention of the catalytic activity) even after seven catalytic cycles along with the non-detectable leaching of the CuO from the paper matrices and ease of separation of the catalyst, made the CuO immobilized paper matrices a superior catalyst. The cellulose matrices not only act as a support to immobilize the CuO nanoparticles but also acts as a co-catalyst due to the presence of ample amount of hydroxyl groups in this biodegradable natural polymer. The synergy of cellulose and CuO in the immobilized paper matrices for the formation of the products can be seen as only 7 or 40 % conversion were estimated when only paper matrices or CuO was used as the catalysts, respectively. Moreover, as substrate the paper matrices has shown great potential as the destruction and re-fabrication for five consecutive cycles could hold more than 95 % of the immobilized CuO in the paper matrices. [ABSTRACT FROM AUTHOR]

Direct internal reforming (DIR) operation of a solid oxide fuel cell (SOFC) is a very attractive concept for downsizing and cost reduction of SOFC systems. This study aimed to develop stable operation of a DIR-SOFC fuelled by biogas. The current-voltage (I-V) curves of 2 × 2 cm 2 planar SOFCs (anode- and electrolyte-supported cells, ASC and ESC, respectively.) were measured at 800 °C in the direct feed of a simulated biogas mixture (CH 4 /CO 2 = 1), and the flexible structured catalyst material (paper-structured catalyst (PSC)) was applied on the anode material for performance enhancement. By applying a hydrotalcite (HT)-dispersed PSC (HT-PSC), the sulfur tolerance of the SOFC in the DIR operation was remarkably improved. By the effect of the HT-PSC, for both ASC and ESC, a stable cell voltage higher than 800 mV was obtained over 200 h at 0.2 A cm −2 in the direct feed of simulated biogas under 5 ppm H 2 S poisoning. [ABSTRACT FROM AUTHOR]

The increasing environmental consideration and the growth of instability of the energy market call for methods that can process the organic fraction of municipal solid waste (OFMSW) into fuel instead of disposal. Due to the pyrolysis and gasification that are efficient procedures to achieve valuable products, gasification of OFMSW with different particle sizes and compositions was carried out in the presence of Ni and Ni-Ce-loaded Y-zeolite in a multizone tubular kiln reactor. During the experiments, 500°C was applied in the first reactor zone, while the 2nd zone was at an elevated temperature of 600°C or 900°C in the presence of steam. The combined pyrolysis and gasification experiments were also carried out without a catalyst with the same operating conditions. The feedstock was collected from the organic fraction of a Hungarian mechanical-biological treatment (MBT) plant and was separated into four different fractions based on particle size: <1 cm dry biomass and fine particles, 1-2 cm paper-rich, 2-6 cm paper and plastic-rich feedstocks, and <6 cm mixture of these fractions. During the experimental work, product yields; gaseous product composition; the ratio of H2/CO, CO2/CO, and CH4/CO; and lower heating value were determined in the function of feedstock composition, the applied temperature, and catalysts. It was found that the hydrogen content and H2/CO ratio of gaseous products were increased due to catalyst application and temperature elevation in the 2nd reactor zone. The addition of Ce to the Ni/Y-zeolite catalyst was advantageous in the case of hydrogen formation at a lower temperature (600°C). The hydrogen and methane content of products obtained from the catalytic pyrolysis-gasification of paper and plastic-rich OFMSWs on elevated temperatures were higher, which increased the lower heating value of those products. Based on the elemental analysis of the obtained solid residues, it was found that paper/plastic-rich feedstock released hydrogen and carbon with a higher extent. 1-2 cm feedstock-related solid residues had the highest H/C ratio which caused a 12.5-12.8 MJ/kg gross heating value. As a result, combined pyrolysis and gasification appear to be an efficient method to attain valuable outputs from OFMSW not only in gas but also in solid products. [ABSTRACT FROM AUTHOR]

Abstract: Architectonics of the paper-structured catalyst for the application to the biofuel reformer or direct internal reforming SOFC (DIRSOFC) was studied. Inorganic fiber network, “paper”, composed of yttria-stabilized zirconia (YSZ) fiber (Zf), alumina fiber (Af) and inorganic binder (Al2O3 sol (As) or ZrO2 sol (Zs) or CeO2 sol (Cs)) was prepared by a simple paper-making process. Then, the catalytic activities of the Ni and Ni–MgO loaded papers called “paper-structured catalysts (PSCs)” for the steam reforming of biodiesel fuels (BDFs) were evaluated. Ni–MgO loaded PSC using Cs as an inorganic binder, Ni–MgO/ZfAfCs, exhibited excellent performance over Ru/γAl2O3 catalyst beads. Formation of light hydrocarbons, especially C2H4, was eliminated and water–gas shift reaction was more promoted compared to the catalyst beads. [Copyright &y& Elsevier]

• Paper machine manufactured photocatalyst papers were investigated. • The photocatalyst papers were soaked by indicator solutions in a laminate structure. • Lateral variations of the photoconversion were followed by reflectance measurements. • Lateral variations show maximum values during the conversion. • The catalyst loading does not influence the overall conversion rate significantly. Paper machine manufacturing of photocatalysts can enable low cost devices for removal of low concentrated pollutants. Lateral variations originating from the paper making process leads to variations of the catalytic activity over the paper area. Paper machine manufactured papers made from tetrapodal ZnO whiskers and kraft pulp were investigated in this test geometry using simulated solar light. Photocatalytic ZnO papers were laminated between polyethylene sheets and an indicator solution seeped into the laminated photocatalytic paper, to create a test geometry where the indicator ink is confined to a small volume between the polyethylene sheets. The photocatalyst papers exhibited surprisingly similar photocatalytic behavior although having different catalyst loading 15, 30 and 45 wt percent. All papers exhibited lateral variations that peaked during the conversion. The results show that production of effective photocatalytic composite papers can be scaled. Further, the results show that variations must be considered for photocatalytic papers. [ABSTRACT FROM AUTHOR]

The effect of catalysts in the form of a transformer copper winding with Kraft paper insulation on the lifetime of transformer oil was studied via ultraviolet-visible (UV-Vis) spectroscopy and Fourier transform infrared (FT-IR) spectroscopy. The tested naphthenic mineral oil was exposed to accelerated thermo-oxidative aging with limited access to air at temperatures of 110, 120, and 130 °C for times ranging from 24 to 2424 h in the presence and absence of catalysts. The UV-Vis technique focused on assessing the change in the color of the oil and quantified a 35%–45% reduction in oil lifetime, depending on the aging temperature, due to the influence of catalysts. The FT-IR analysis focused on the decrease in the spectral band at 3650 cm−1, which corresponds to the low-temperature antioxidant present in the oil, and quantified the 35% reduction in the oil lifetime independent of the aging temperature. This high rate of reduction in the transformer oil lifetime points to the dominant catalytic role of the Kraft paper and copper during the aging process of the transformer insulation system. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of NO not only offers an attractive alternative to the Haber–Bosch process for ambient NH3 production but mitigates the human‐caused unbalance of nitrogen cycle. Herein, we report that MoS2 nanosheet on graphite felt (MoS2/GF) acts as an efficient and robust 3D electrocatalyst for NO‐to‐NH3 conversion. In acidic electrolyte, such MoS2/GF attains a maximal Faradaic efficiency of 76.6 % and a large NH3 yield of up to 99.6 μmol cm−2 h−1. Using MoS2 nanosheet‐loaded carbon paper as the cathode, a proof‐of‐concept device of Zn‐NO battery was assembled to deliver a discharge power density of 1.04 mW cm−2 and an NH3 yield of 411.8 μg h−1 mgcat.−1. Calculations reveal that the positively charged Mo‐edge sites facilitate NO adsorption/activation via an acceptance–donation mechanism and disfavor the binding of protons and the coupling of N−N bond. [ABSTRACT FROM AUTHOR]

A core-shell catalyst supported on the carbon fiber paper was developed for the effective electrocatalytic reduction of concentrated nitric acid (4.0 M). The potential range of cyclic voltammetry deposition was adjusted to investigate the influence of the chemical state of electrodeposited Ir on concentrated nitric acid reduction. The results indicate that a core of Pt with a thin IrO 2 shell shows greatly enhanced catalytic activity comparing to the nano-Pt. A Pt@IrO 2 core-shell catalyst was synthesized by a two-step cyclic voltammetry. It shows a high reactivity toward electrocatalytic reduction of concentrated nitric acid (4.0 M). Unlabelled Image • The Pt core with Ir shell catalyst was designed for the effective nitric acid reduction. • The chemical state of Ir shell plays an important role in the reduction process. • The Pt@IrO 2 /CFP electrode shows a higher current density than that of Pt@Ir/CFP. [ABSTRACT FROM AUTHOR]

Bimetallic nanomaterials with enhanced activity and stability have been extensively studied as emerging catalysts for hydrogen evolution reaction (HER). Expensive and environmentally unfriendly chemical synthesis routes inhibit their large-scale applications. In this work, we developed a facile and green synthesis of Pd–Au alloy nanoparticles (NPs) dispersed on carbon fiber paper (CFP) by plant-mediated bioreduction coupled with self-assembly. Engineering the morphology and composition of bimetallic catalysts synthesized by plant extracts on complex substrate is achieved. The resulting NPs are uniform in shape and have a spherical morphology with an average diameter of ∼180 nm, in which the molar ratio of Au/Pd is near 75:25 and the catalysts loading is about 0.5 mg cm −2 . The Pd–Au/CFP hybrid electrode exhibits an excellent HER performance with a Tafel slope of 47 mV dec −1 and an exchange current density of 0.256 mA cm −2 . Electrochemical stability tests through long-term potential cycles and potentiostatic electrolysis further confirm the high durability of the electrode. This development offers an efficient and eco-friendly catalysts synthesis route for constructing water-splitting cells and other electrocatalytic devices. [ABSTRACT FROM AUTHOR]

A novel microstructured catalyst that consists of Cu/ZnO catalyst powders and ceramic fibers was successfully prepared using pulp fibers as a tentative matrix by a papermaking technique. As-prepared material, called a paper-structured catalyst, possessed porous microstructure with layered ceramic fiber networks (average pore size ca. 20 μm, porosity ca. 50%). In the process of methanol autothermal reforming (ATR) to produce hydrogen, paper-structured catalysts demonstrated both high methanol conversion and low concentration of undesirable carbon monoxide as compared with catalyst powders and pellets. The catalytic performance of paper-structured catalysts depended on the use of pulp fibers, which were added in the paper-forming process and finally removed by thermal treatment before ATR performance tests. Confocal laser scanning microscopy and mercury intrusion analysis suggested that the tentative pulp fiber matrix played a significant role in regulating the fiber-network microstructure inside paper composites. Various metallic filters with different average pore sizes, used as supports for Cu/ZnO catalysts, were subjected to ATR performance tests for elucidating the pore effects. The tests indicated that the pore sizes of catalyst support had critical effects on the catalytic efficiency: the maximum hydrogen production was achieved by metallic filters with an average pore size of 20 μm. These results suggested that the paper-specific microstructures contributed to form a suitable catalytic reaction environment, possibly by promoting efficient diffusion of heat and reactants. The paper-structured catalyst with a regular pore microstructure is expected to be a promising catalytic material to provide both practical utility and high efficiency in the catalytic gas-reforming process. [ABSTRACT FROM AUTHOR]

Transition metal phosphates with hollow structure have attracted substantial attentions as high-performance electrocatalyst for oxygen evolution reaction (OER). However, these electrocatalytic materials need conductive carrier to realize efficient charge transfer and further improve the OER activity. In this work, ZIF-67 derived hollow NiCo phosphate nanocages supported by waste paper-based carbon aerogel (NCP@WPCA) was prepared as high-efficiency and stable electrocatalyst. Benefited from the enhanced electrochemical active surface area and fast gas emission, the NCP@WPCA catalyst exhibits superior OER activity with low overpotential of 351 mV at current density of 10 mA cm−2, along with good stability in alkaline solution. Additionally, the waste paper-based carbon aerogel as the carrier for electrocatalysts achieves low-cost waste reuse. [Display omitted] [ABSTRACT FROM AUTHOR]

ABSTRACT Surface-confined electropolymerization allowed us to easily prepare homogeneous polymer composite paper structures. The fabrication of freestanding graphene (Gr)-based composite electrodes is very important for many modular approaches in electrochemical applications, such as fuel cells, supercapacitors, and sensors. A Gr composite paper electrode doped with polymeric films of pyronin Y was fabricated by two repetitive simple applications: vacuum filtration and surface-confined electropolymerization. The characterization of this composite paper was done with scanning tunneling microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, powder X-ray diffraction spectroscopy, Raman spectroscopy, UV-visible absorption spectroscopy, four-point probe conductivity measurement, cyclic voltammetry, and electrochemical impedance spectroscopy. The freestanding composite paper demonstrated good electrocatalytic activity for the electrooxidation of dopamine; this indicated that this composite paper could be used for the amperometric quantification of dopamine in real samples. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45139. [ABSTRACT FROM AUTHOR]

In recent years, the catalyst efficiency of hydrogen evolution reaction (HER) has been extensively studied. However, the stability of catalysts at high current densities is still a challenge. Herein, layered Ni−Co−P was electrodeposited on carbon fiber paper (CFP) via cyclic voltammetry (CV). This low‐cost electrode exhibits high efficiency and excellent durability for HER in 1 M KOH. To achieve current densities of 10, 100, 500, and 1000 mA cm−2, Ni−Co−P/CFP required overpotentials of 49, 95, 170, and 295 mV, respectively. The layered structure allows the catalyst to fall off layer by layer. After the outer layer of catalyst falls off, the inner layer of catalyst will be exposed to continue working. After 300 h of HER at 1000 mA cm−2, Ni−Co−P/CFP still has a regular morphology and high efficiency. Our work shows that layered Ni−Co−P/CFP has excellent prospects for practical applications. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) have been widely studied for electrochemical CO2 reduction reaction (CO2RR). However, the application of negative potential tends to trigger its structural reconstruction and component alteration. It is of great significance to study the relationship between the structural evolution of MOF‐derived materials and product selectivity under the reaction conditions. Herein, we fabricate a HKUST‐1 thin film on carbon fiber paper by a facile electrodeposition approach to investigate the variation of CO2RR activity with HKUST‐1 structural reconstruction. During the CO2RR process, the HKUST‐1 reconstructs into two structures successively over time: 3D nanospheres composed of numerous small fragments and 3D nano‐network composed of cross‐linked nanobelts in different directions. The former shows a better catalytic activity due to more active sites, lower charge transfer resistance and higher Cu+/Cu0 ratio. The optimum Faradaic efficiency (FE) of C2 products (ethylene and ethanol) reaches 58.6 % at −0.98 V versus reversible hydrogen electrode (RHE). [ABSTRACT FROM AUTHOR]

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Ni‐promoted electrocatalytic biomass reforming has shown promising prospect in enabling high value‐added product synthesis. Here, we developed a novel hybrid catalyst with Ni nanosheet forests anchored on carbon paper. The hybrid catalyst exhibits high efficiency in electrooxidation of HMF to FDCA coupling with H2 production in high purity. The Ni nanosheets have small crystal grain sizes with abundant edges, which is able to deliver an efficient HMF oxidation to FDCA (selectivity >99 %) at low potential of 1.36 VRHE with high stability. The post‐reaction structure analysis reveals the Ni nanosheets would transfer electrons to carbon and readily turn into NiOx and Ni(OH)x during the reaction. DFT results suggest high valence Ni species would facilitate the chemical adsorption (activation) of HMF revealing the reaction pathway. This work emphasizes the importance of the precise control of Ni activity via atomic structure engineering. [ABSTRACT FROM AUTHOR]

A long-standing goal has been to create artificial enzymes with natural enzyme-like catalytic activity. Herein, a laccase-mimicking catalyst (GSH-Cu) is designed by simulating the copper active sites and spatial amino acid microenvironment of natural enzymes. In particular, the engineered GSH-Cu shows a catalytic function that conforms to Michaelis-Menten kinetics of natural laccase. The high catalytic activity of GSH-Cu can be easily inhibited by thiram through surface passivation to produce copper nanoparticles. We demonstrate that the developed GSH-Cu with high stability and recyclability can be used to fabricate effective colorimetric sensor for sensitive detection of thiram. The resulting absorption intensity can be employed to quantify thiram in the range of 2.5–250 ng mL−1, which meets the detection requirement in fruit. Bestowed with the feasibility analysis of colorimetric output, a portable platform is designed by integrating GSH-Cu based test paper with a conventional smartphone for conveniently on-site quantified thiram. The proposed strategy about engineering enzyme-mimicking catalysts with excellent catalytic performance will open avenues for boosting the sensing application. [ABSTRACT FROM AUTHOR]

[Display omitted] • Paper-based Cu 2 O photocathode was collaboratively modified with FeOOH and CuS. • Both the charge carrier separation and electron acceptor reduction were promoted. • Dual-hydrophilic-walls hollow channel was used for promoting homogeneous reaction. • Lab-on-paper homogeneous photocathodic bioassay of microRNA was proposed. Herein, a simple but effective photocathodic signal enhancement strategy was developed based on FeOOH/Cu 2 O/CuS photocathode-enabled simultaneous promotion on charge carrier separation and electron acceptor reduction, and applied to construct lab-on-paper homogeneous cathodic photoelectrochemical (PEC) bioassay via dual-hydrophilic-walls hollow channel (DHWHC) design and target-triggered all-in-one hemin@G-rich DNA release. More concretely, FeOOH as hole extraction layer fleetly extracted photogenerated holes from Cu 2 O, while the photogenerated electrons rapidly transferred to CuS, as electron transfer/consumption accelerator, by photoinduced interfacial charge transfer (IFCT), achieving the efficient charge carrier separation. In the IFCT process, the Cu(II) in CuS was reduced to Cu(I) and it could be oxidized back to Cu(II) by electron acceptor (O 2), forming a Cu(II)/Cu(I) redox circular reaction, which could effectively accelerate the transfer/consumption of photogenerated electrons and further promote electron acceptor reduction. Thus, the simultaneous promotion on charge carrier separation and electron acceptor reduction was fulfilled by FeOOH/Cu 2 O/CuS photocathode, producing a strongly enhanced photocathodic signal. On account of the high mass-transfer rates of DHWHC, the mediation of electron acceptor generation through target-triggered hemin@G-rich DNA release, and the proposed signal enhancement strategy, the ultrasensitive lab-on-paper homogeneous PEC microRNA-141 detection was realized with high selectivity, reproducibility, and stability. This work rendered practical guidelines for developing high-performance lab-on-paper cathodic PEC bioanalysis systems. [ABSTRACT FROM AUTHOR]

We propose an innovative 3-step manufacturing technique for the synthesis of the catalyst layer of proton exchange membrane electrodes directly over a gas diffusion layer consisting of carbon paper (CP). In the first step, a carbon synthesis catalyst was formed in a bicontinuous microemulsion. In the second step, carbon nano-networks (CNNs) were directly grown over CP by thermal chemical vapor deposition of ethene over the metal catalyst embedded in the simultaneously carbonized microemulsion matrix. In the third step, the electrocatalyst, here Pt, was deposited on the CNNs. The influence of surfactant type, Na-AOT or Triton X-100, carbon synthesis catalyst type, Fe, Co or Pt, and loading on the electrolyte accessible surface area (ESA) and carbon corrosion resistance was evaluated in a three-electrode half-cell. CNNs grown from Fe and synthetized in Na-AOT microemulsions resulted as the best combination in terms of ESA and carbon corrosion resistance and were used for subsequent investigations. The CNNs grown on CP (CNNs/CP) were electrochemically oxidized prior to Pt electro-deposition by means of potential cycling. The effect of oxidation of the CNNs on the size and spatial distribution of the electrodeposited Pt catalyst was evaluated. Increasing the number of functionalizing oxidation cycles from 0 to 100 decreased the average catalyst crystallite size from 19 to 9 nm. The CNNs/CP samples showing the highest electrochemically active surface area (ECSA) were compared to a commercial catalyst with respect to ECSA, catalyst utilization, and durability to potential cycling. The ECSA for the CNNs/CP samples turned out to be lower than that of the commercial catalyst due to the larger catalyst size. On the other hand, the CNN/CP samples proved to be more durable and higher Pt utilization was achieved. [ABSTRACT FROM AUTHOR]

Abstract: In this study, performance of solid oxide fuel cell (SOFC) connected with paper-structured catalyst (PSC) was evaluated in the direct feed of wet oleic fatty acid methyl ester (oleic-FAME, C19H36O2), which is a mono-unsaturated component of practical biodiesel fuels (BDFs), in the steam to carbon ratio (S/C) range between 2.0 and 3.5, and high current density of 1 A cm−2 (at 0.7 V) was recorded at 800 °C. Long term stability of oleic-FAME fueled SOFC was achieved by the incorporation of PSC into SOFC even under severe operating condition prone to coking (direct feed of unsaturated hydrocarbon with carbon number 19 and low S/C ratio of 2.0). After 100 h test, coking was not observed in both SOFC anode and PSC. [Copyright &y& Elsevier]

Abstract: The present work demonstrated that secondary pulp/paper sludge powder, with a higher heating value of 18.3MJ/kg on a dry basis, could be effectively converted into liquid oil products by direct liquefaction in hot-compressed water with and without catalyst. Treatments of secondary pulp/paper sludge in water at 250–380°C for 15–120min in the presence of N2 atmosphere resulted in yields of water-soluble oils at 20–45wt% and yields of heavy oils at 15–25wt%, with higher heating values of 10–15 and >35MJ/kg, respectively. The higher caloric values for the heavy oil products were accounted for by their compositions of long-chain carboxylic acids, heterocyclic nitrogen compounds and phenolic compounds and derivatives as evidenced by the gas chromatograph (GC)/MS measurements. The liquefaction product yields were significantly influenced by the liquefaction temperature, the residence time, the initial biomass concentration, catalysts and the liquefaction atmosphere (inert or reducing). Within the temperature range (250–380°C) tested, the lowest temperature produced the highest yield of total oils (at 60wt%), while the greatest yield of heavy oil (at about 24wt%) was obtained at 350°C. If the temperature was fixed at 280°C, a greater yield of heavy oil (reaching as high as 25wt% for 120min) was obtained as the length of reaction time increased. Similarly, a higher initial biomass concentration produced a greater yield of heavy oil but a reduced yield of water-soluble oil. The presence of 0.1M K2CO3 dramatically enhanced organic conversion, but suppressed the formation of both heavy oil and water-soluble oil. The use of the two alkaline earth metal catalysts, i.e., Ca(OH)2 and Ba(OH)2, did not alter organic conversion, but it catalyzed the formation of water-soluble oil and produced higher yields of total oil products. It was also demonstrated that the reducing atmosphere (i.e., H2) in the liquefaction process promoted the heavy oil formation while suppressing the water-soluble oil formation. With the presence of 0.1M Ca(OH)2 and 2MPa H2, liquefaction of the sludge powder in water at 280°C for 60min produced a higher yield of heavy oil (26wt%), almost two times as high as that in N2 (13.6wt%), resulting in a greater net energy efficiency. It was thus suggested that direct liquefaction of secondary pulp/paper sludge in hot-compressed water with Ca(OH)2 catalyst and in the presence of H2 could be an effective approach to recovering energy from the waste for production of liquid oil products. [Copyright &y& Elsevier]

A novel paper-based material containing titanium dioxide (TiO2) photocatalyst was successfully prepared by a papermaking technique with the internal addition of inorganic fibers on which TiO2 particles were supported. Photodegradation performance of acetaldehyde gas, an indoor pollutant, and the durability of the TiO2-containing papers were investigated under UV irradiation. Ceramic fiber suspension and polydiallyldimethylammonium chloride as a cationic flocculant were mixed, followed by the addition of TiO2 suspension and anionic polyacrylamide. Subsequently, the inorganic mixture was poured into a pulp suspension, and TiO2 handsheets then prepared by a papermaking method. The tensile strength of TiO2-containing paper without a ceramic carrier decreased by more than 30% after 240-h UV irradiation (2 mW/cm2), although the strength of the TiO2 sheet with ceramic fibers remained reasonably stable. The efficiency of acetaldehyde decomposition by the TiO2 paper containing an inorganic carrier was nearly equal to that of the carrier-free TiO2 paper. Scanning electron microscopic observation suggested that most TiO2 particles were predominantly supported on the inorganic fiber matrix, and were mostly out of contact with organic pulp fibers. The TiO2 paper with an inorganic carrier demonstrated both excellent photocatalytic performance and durability, which before had been mutually incompatible for organic materials containing TiO2 photocatalyst. The two-stage mixing procedure for TiO2 sheet-making is promising for the simple manufacture of high performance paper with photocatalytic ability. [Copyright &y& Elsevier]

Nanoclusters of Pt were electrochemically deposited on a conducting polymer, namely, poly(3,4-ethylenedioxythiophene) (PEDOT), which was also electrochemically deposited on carbon paper current collector. PEDOT facilitated uniform distribution of Pt nanoclusters, when compared with Pt electrodeposition on bare carbon paper substrate. Spectroscopy data indicated absence of any interaction between PEDOT and Pt. The electrochemically active surface area as measured from carbon monoxide adsorption followed by its oxidation was several times greater for Pt-PEDOT/C electrode in comparison with Pt/C electrode. The catalytic activity of Pt-PEDOT/C electrode for electrooxidation of formic acid was significantly greater than that of Pt/C electrode. Amperometry data suggested that the electrodes were stable for continuous oxidation of HCOOH. [ABSTRACT FROM AUTHOR]

Abstract: This study investigated the feasibility of the enhanced efficiency of energy yields in the catalytic gasification processes of paper-reject sludge. The experiments were conducted by controlling the temperatures that ranged from 600 °C to 900 °C with the addition of the mineral catalyst (calcium oxide, CaO) with a ratio that ranged between 10 percent and 20 percent by weight. According to the experimental results, increasing gasification temperatures will enhance the lower heating value (LHV) of syngas in the gasification of paper-reject sludge. The LHV of syngas increased from 10.6MJ/Nm3 to 21.1MJ/Nm3 with increased temperatures from 600 °C to 900 °C. The energy density of syngas was also increased from 1.13 to 4.56, as gasification temperature operated between 600 °C and 900 °C. This implied that the energy utilization of syngas, produced by gasification, could increase approximately four times the energy content of paper-reject sludge. Besides this, the energy yield efficiency in gasification will be enhanced by the tested mineral catalyst. In the case of gasification temperatures operating from 600 °C to 900 °C, the LHV of syngas increased significantly from 13.04MJ/Nm3 to 21.52MJ/Nm3 by the tested mineral catalyst. Meanwhile, the results of the energy density as well as the carbon conversion rate in catalytic gasification indicated that the results were 2.8–4.59 and above 95%, respectively. The experimental results of this research confirm that it is possible to improve the efficiency of tar reduction and energy yields using a tested mineral catalyst and can promote the potential for renewable energy in the application of paper-reject sludge. [Copyright &y& Elsevier]

[Display omitted] • A bifunctional flexible Pt/TiO 2 -γ-Al 2 O 3 nanofiber paper was successfully prepared. • The PTA sample can efficiently decompose HCHO to CO 2 and H 2 O at room temperature. • PTA1 exhibited better catalytic activity and stability. • The surface coating of TiO 2 in PTA catalyst plays an important role for its performance. • The PTA sample also exhibits good filtration performance for fine particles. A flexible Pt/TiO 2 /γ-Al 2 O 3 nanfiber paper (PTA) was successfully prepared by an electrospinning-coating-NaBH 4 reduction method. The catalytic performance for formaldehyde (HCHO) oxidation over PTA with different Pt contents was investigated at room temperature. The results show that PTA exhibits higher catalytic activity and stability than Pt/γ-Al 2 O 3. The TiO 2 coating can promote the transformation of intermediate species and the desorption of CO 2. The PTA1 with 1 wt% Pt shows the best catalytic activity and good stability. In the view of activity and cost, 0.5 wt% Pt is the optimal Pt content. The TiO 2 coating not only plays an important role in improving the activity and stability of PTA, but also acts as a protective shell of γ-Al 2 O 3 fiber, which greatly reduces the risk of alkali etching during preparation and maintains the good flexibility of PTA. The dioxymethylene (DOM), formate/carbonate species, CO are the intermediate species in HCHO oxidation over PTA. In addition, PTA exhibits good filtration performance for fine particles as well as good fluid permeability. Because of the high efficiency and flexibility of PTA composite catalytic material for HCHO oxidation with good filtration performance for fine particles, it will be a promising candidate in air purification. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photoreversible color switching systems have been integrated by reducing agent of triethanolamine, catalyst of β-FeOOH nanorods. • With high switching rate, high reversibility (>10 cycle), the new system could be broad use in rewritable paper. • The rewritable paper is highly applicable as self-erasing rewritable media for printing. • The rewritable paper can be applied for a data encoding and reading strategy. Nowadays, photo reversible color switching systems (PCSS) are always limited by some requirements, such as good stability, low toxicity, fast light response, long cycling performance and low production cost, therefore, it is a huge challenge to develop such a system that integrates beneficial features. Herein, a new type of PCSS have been demonstrated, which integrated reducing agent of triethanolamine (TEOA), catalyst of β-FeOOH nanorods and the redox driven color conversion characteristics of redox dyes. The system has the advantages of high switching rate, high reversibility (>10 cycles), wavelength selective response, safety and less light damage, which can be widely used in rewritable paper. As-prepared rewritable paper has high contrast, high resolution, suitable printing time and good reversibility, which is in line with the environmental protection concept of green printing. Rewritable paper is a kind of self-erasable rewritable medium which is highly suitable for printing. Environmental protection film has the advantages of low cost, convenient preparation and recycling. It is expected to replace the traditional writing, printing paper, existing systems and make a big step forward to practical application. Even more surprising, it also can be applied for a data encoding and reading strategy. [ABSTRACT FROM AUTHOR]

Co 3 O 4 catalysts supported on paper-like stainless steel fibers (PSSF) were prepared by MOFs-templated (M) method and applied for catalytic combustion of isopropanol. Physicochemical properties of the as-synthesized Co 3 O 4 catalysts were investigated by SEM, EDS mapping, TEM, XRD, BET, XPS and H 2 -TPR, respectively. Characterization results of SEM and TEM shown that Co 3 O 4 (M)-350 and Co 3 O 4 (M)-400 still remained the dodecahedron shape of the ZIF-67 precursor and possessed porous structures. The XPS results shown that the ratio of Co3+/Co2+ and O c /O c ​+ ​O a ​+ ​O l firstly increased and then decreased with the increase of calcination temperature. Among the as-synthesized catalysts, Co 3 O 4 (M)-400 exhibited the highest activity for the catalytic combustion of isopropanol with the T 50 and T 90 values of 258 ​°C and 281 ​°C, respectively, which was associated with high BET surface area, high amount of Co3+ species and abundant surface chemisorbed oxygen. Moreover, Co 3 O 4 (M)-400 was employed as a structured catalyst for isopropanol combustion, the catalytic kinetics were studied based on different feed concentration, bed height and GHSV. The experimental results indicated that the T 50 and T 90 of isopropanol combustion over Co 3 O 4 (M)-400 with the bed height of 2 ​cm were increased slightly as the GHSV and feed concentration of isopropanol increased. Fig. 1 Preparation process and Catalytic performance of Catalysts. [Display omitted] • A novel gradient porous Co 3 O 4 (M)-X catalyst was prepared by MOFs-templated method. • The effect of preparation methods on properties of Co based catalysts were studied. • Co 3 O 4 (M)-400 shown the highest isopropanol catalytic combustion performance. [ABSTRACT FROM AUTHOR]

Development of a neutral Zn–air battery is of much significance due to the high stability of zinc in a neutral electrolyte. Here, Ni/Co-doped C–N nanotube composites (C–N, Ni/C–N, Co/C–N, and Ni–Co/C–N) as efficient oxygen reduction reaction (ORR) electrocatalysts in a neutral medium have been prepared by direct pyrolysis of Ni/Co salt, dicyandiamide (DCD) and glucose. Among the synthesized catalysts, Ni–Co/C–N presents a high ORR current density of 8.5 mA ⋅ cm − 2 in a 0.5 mol ⋅ L − 1 KNO3 solution. The ORR electron transfer number of the catalyst Ni–Co/C–N is 3.8, indicating that O2 is almost completely reduced to H2O. A neutral zinc–air battery utilizing a 0.5 mol ⋅ L − 1 KNO3 solution has been assembled by using the prepared composite catalyst coated on carbon paper as an air cathode, and Zn plate as an anode. The battery with the cathode catalyst Ni–Co/C–N delivers the open-circuit voltage of 1.13 V and the maximum power density of 65 mW ⋅ cm − 2 . The constant discharge current density of 50 mA ⋅ cm − 2 , 100 mA ⋅ cm − 2 and 150 mA ⋅ cm − 2 can last 202 h, 93 h and 11 h, respectively. A stable voltage plateau appears at various discharge current densities. The neutral zinc–air battery can be repeatedly discharged after replacing the zinc anode. Results indicate that the synthesized Ni–Co/C–N catalyst is an excellent cathode material applied to a neutral zinc–air battery, showing broad application prospects as a mobile power source. Ni/Co-doped C–N nanotube composites have been prepared through direct pyrolysis of Ni/Co salt, dicyandiamide and glucose. The Ni–Co/C–N catalyst presents a more uniform size of nanotube particles with diameter as small as 30 nm, and it possesses excellent ORR performance as the cathode catalysts of neutral Zn–air battery. [ABSTRACT FROM AUTHOR]

Abstract: This article reports two routes, microwave-assisted synthesis and thermal reduction, to deposit silver nanoparticles on oxidized carbon paper (CP) electrodes. In comparison, as-grown Ag particles, prepared by the microwave-assisted route, exhibit uniform particle size and well-dispersion over the CP substrate. Electrochemical behavior of Ag–CP electrodes is characterized by cyclic voltammetry and AC impedance spectroscopy, incorporated with equivalent circuit. Both the catalyst electrodes display redox reversibility within the potential region of 0–0.5V vs. saturated calomel electrode (SCE) in 1M NaOH. According to the Randles–Sevcik plot, the diffusion coefficient under voltammetric regime ranges from 9.06×10−10 to 3.33×10−10 cm2 s−1. These differences of diffusion coefficient and capacitance are ascribed to the resulting Ag nanocatalysts with small particle size and no aggregation. On the basis of the results, the microwave-assisted approach for depositing nano sized Ag catalysts on CP electrodes shows the potential in application of alkaline fuel cells because of its fast synthesis, high activity, and simplicity. [Copyright &y& Elsevier]

Abstract: The study examines the water/oil repellency and the sliding behavior of carbon papers (CPs) decorated with carbon nanotube (CNT) forest, prepared by using a catalytic chemical vapor deposition. The topography showed that CNTs with 20–40nm grown on CPs form a hierarchical nano/submicron scale roughness. The CNT–CP composite surface with a thin fluoro-silica coating exhibits excellent water/oil repellency (contact angle >150°) with low sliding angles (SAs), i.e., SA: ∼6° and ∼18° for water and ethylene glycol (EG) droplets, respectively. Taking into account Young–Duprè’s equation incorporated with the Cassie parameter, the work of adhesion (W ad) between droplets and CP surface is significantly reduced because the decoration of CNTs offers an air cushion to repel the drop penetration. The appearance of CNTs contributes area fractions in contact with air, 7.4% and 14.1%, to resist water and EG drops, respectively. The analysis of W ad confirms that the smaller the W ad value, the smaller the SA value reached, thus favoring the self-cleaning effect. [Copyright &y& Elsevier]

Abstract: Production of xylan-degrading enzymes, endo-β-xylanase (EC 3.2.1.8), β-xylosidase (EC 3.2.1.37), α-l-arabinofuranosidase (EC 3.2.1.55 and α-galactosidase (EC 3.2.1.22) by Aspergillus oryzae NRRL 1808 was investigated in solid-state fermentation using eucalyptus soda-anthraquinone and bagasse soda pulps as carbon feedstock. The impact of different nitrogen sources and initial fermentation pH on enzyme production was studied in medium optimisation experiments using fractional factorial design. The use of ammonium nitrate and corn steep liquor favoured xylanase production on eucalyptus pulp, whereas potassium nitrate and corn steep liquor increased xylanase yields on bagasse pulp. Xylanase production on eucalyptus and bagasse pulps under optimised conditions peaked on day 4 of cultivation (3200 and 2675IUg−1 dry matter, respectively) which represents an increase in xylanase activity of 60% and 37%, respectively, over the non-opimised conditions. Biobleaching of eucalyptus and bagasse pulps was carried out using the whole fermented material (residual pulp, fungal biomass and in situ enzymes) from the cultivation of A. oryzae without a prior down streaming of the in situ enzymes from these pulps. Overall, the bagasse pulp was more susceptible to enzyme bleaching than eucalyptus pulp. In all instances, a greater brightness gain was induced with the in situ solid-state enzymes (0.9–3.0 points brightness increase) than a commercial enzyme control (0.8–2.5 points). At the same bleaching costs (US$ 1 or 3t−1 pulp), the solid-state enzymes produced under optimised conditions were 20–36% more efficient in improving the brightness of paper pulp than the commercial enzyme. However, the presence of increased levels of side chain xylan degrading enzymes in the optimised medium did not improve the bleaching abilities of xylanase. It was demonstrated that bagasse pulp could successfully be used as carrier of A. oryzae enzymes in biobleaching of eucalyptus pulp without sacrificing the bleaching efficiency of xylanase. [Copyright &y& Elsevier]

Nickel nanoparticles supported by commercial carbon paper (CP) are prepared by pulsed laser deposition with deposition time of 3, 6, and 12 min as a catalyst for urea electro-oxidation. The surface conditions and the morphologies of the prepared electrodes have been characterized by Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy. Urea electro-oxidation reaction in KOH solution on the Ni/CP electrodes is investigated by cyclic voltammetry and chronoamperometry. The results show that the electrode with less Ni nanoparticle agglomeration shows higher peak current density, which was achieved in the 3 min deposition samples when normalized by electroactive surface areas. However, the highest current normalized by the area of the carbon paper was achieved in the 6 min deposition sample due to the larger quantity of Ni nanoparticles. All the samples show good stability. Our results suggest that the low density, low cost, and environmental friendly CP can be used as support for Ni nanoparticle as a catalyst for urea electro-oxidation. It thus has great potential for many applications involving urea oxidation, such as wastewater treatments. [ABSTRACT FROM AUTHOR]

• Dendritic In-doped Cu@Cu 2 O catalyst is prepared by co-electrodeposition method. • Doped-In content can tailor Cu+/Cu0 ratio, charge distribution, morphology and ECSA. • Cu+/Cu0 ratio plays a vital role on enhancing FE CO and partial current density at low In doping. • 3.7% In-Cu sample shows the highest FE CO of 87.6 ± 2.2 % and j CO of 9.7 ± 1.04 mA cm -2. Element doping is an effective strategy to enhance the selectivity of electrochemical carbon dioxide reduction. In this work, a dendritic core-shell In-doped Cu@Cu 2 O catalyst is prepared by co-electrodeposition method on carbon fiber paper for selective electroreduction of CO 2 to CO. Faradaic efficiency of producing CO over this dendritic In-doped Cu@Cu 2 O reaches 87.6 ± 2.2% with total current density of 11.1 ± 0.85 mA cm−2 at −0.8 V vs RHE, which outperforms most of the reported Cu-based electrocatalysts. The excellent performance is mainly derived from charge re-distribution and the enhanced intrinsic activity due to the formation of In-doped Cu 2 O layer. Meanwhile, the Cu+/Cu0 can be adjusted by tailoring the doped-In content. The relatively high ECSA and small charge transfer resistance are also conducive to improve the selectivity and activity. The oxyphilic In metal incorporated into the copper lattice can well stabilize the intermediate *COOH through enhancing interaction with O-ends of *COOH. This work provides a facile approach and a deep insight on design and synthesis of high efficiency hybrid electrocatalysts. [ABSTRACT FROM AUTHOR]