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The practical application of lithium–sulfur batteries (LSBs) is severely hindered by the undesirable shuttling of lithium polysulfides (LiPSs) and sluggish redox kinetics of sulfur species. Herein, a series of ultrathin single‐atomic tungsten‐doped Co3O4 (Wx‐Co3O4) nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized. Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping, the Wx‐Co3O4 not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species, leading to accelerated electrode kinetic. As a result, LSB cathodes with the use of 5.0 wt% W0.02‐Co3O4 as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g−1 at 0.2 and 5.0 C, respectively, and maintain a high reversible capacity of 644.6 mAh g−1 at 1.0 C (1.0 C = 1675 mA g−1) after 500 cycles. With a high sulfur loading of 5.5 mg cm−2 and electrolyte–electrode ratio of 8 μLelectrolyte mgsulfur−1, the 5.0 wt% W0.02‐Co3O4‐based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm−2 at 0.1 C after 50 cycles with an initial capacity retention of 84.7%. [ABSTRACT FROM AUTHOR]

Abstract The practical application of lithium–sulfur batteries (LSBs) is severely hindered by the undesirable shuttling of lithium polysulfides (LiPSs) and sluggish redox kinetics of sulfur species. Herein, a series of ultrathin single‐atomic tungsten‐doped Co3O4 (Wx‐Co3O4) nanosheets as catalytic additives in the sulfur cathode for LSBs are rationally designed and synthesized. Benefiting from the enhanced catalytic activity and optimized electronic structure by W doping, the Wx‐Co3O4 not only reduces the shuttling of LiPSs but also decreases the energy barrier of sulfur redox reactions of sulfur species, leading to accelerated electrode kinetic. As a result, LSB cathodes with the use of 5.0 wt% W0.02‐Co3O4 as the electrocatalyst show the high reversible capacities of 1217.0 and 558.6 mAh g−1 at 0.2 and 5.0 C, respectively, and maintain a high reversible capacity of 644.6 mAh g−1 at 1.0 C (1.0 C = 1675 mA g−1) after 500 cycles. With a high sulfur loading of 5.5 mg cm−2 and electrolyte–electrode ratio of 8 μLelectrolyte mgsulfur−1, the 5.0 wt% W0.02‐Co3O4‐based sulfur cathode also retains a high reversible areal capacity of 3.86 mAh cm−2 at 0.1 C after 50 cycles with an initial capacity retention of 84.7%.

The furniture industry is one of the most dynamically developing sectors of the Polish economy. Unfortunately, due to national law, it involves producing a significant amount of wood-based waste, which can only be incinerated in installations that meet the requirements for waste incineration or co-incineration plants. This is due to the presence of various types of chemical additives in post-production residues, which increases the emission of hazardous compounds into the atmosphere during combustion. This article presents an analysis of the impact of the use of catalytic additives on the amount of emissions produced from the combustion of wood-based waste. For this purpose, the analyzed material was pelletized by mixing it with the DESONOX catalyst or by spraying the fuel with the DESONOX + H2O solution in a 1:1 ratio. Catalytic substances were introduced into the fuel until a concentration of 0.1% of its mass was obtained. The use of catalysts has significantly reduced CO and NOX emissions into the atmosphere. In the case of carbon monoxide, the most effective was Ad2 (reduction by 44%), and in the case of nitrogen oxides, Ad1 (reduction by 31%) achieved the best outcome. The results from this analysis may be an indication for Polish legislation encouraging furniture plants to burn this waste in their own units using catalytic substances. [ABSTRACT FROM AUTHOR]

This paper presents the research results of the effect of using calcium oxide and potassium permanganate on the combustion of pellets from wheat bran and beet pulp. The measurements were performed in the technical laboratory of the Centre of Energy Utilization of Non-Traditional Energy Sources in Ostrava. The research examined the effect of the use of chemical substances on the amount of air pollutants from biomass thermal conversion in a low-power boiler and the process temperature. First, we performed technical and elementary analyses of agricultural waste. The raw material was then comminuted, mixed with a selected additive, pelletized, and finally burned in a low-power boiler. The additive was added in three proportions: 1:20, 1:10, and 1:6.67 (i.e., 15%) relative to the fuel weight. The combustion process efficiency was measured using a flue gas analyzer and three thermocouples attached to the data recorder. From the measurement results, we were able to determine the percentage reduction of pollutant emissions into the atmosphere (CO, NOx, and SO2) due to the use of additives. Because emission standards are becoming increasingly stringent and fuel and energy prices are rising, the results presented in this article may be useful to agri-food processing plants that want to manage these materials thermally. [ABSTRACT FROM AUTHOR]

Based on the positive influence of carbon materials and transition metals, a new type of Mg-based composites with particle size of ∼800 nm has been designed by doping hydrogenated Mg–Ni–La alloy with multi-walled carbon nanotubes (MWCNTs) and/or Co nanoparticles. The microstructures, temperature related hydrogen absorption/desorption kinetics and dehydrogenation mechanisms are investigated in detail. The results demonstrate that MWCNTs and Co dispersedly distribute on the surface of Mg–Ni–La particles after high-energy ball milling due to powders' repeated cold welding and tearing. The experimental samples exhibit improved hydrogen storage behaviors and the addition of MWCNTs and Co can further accelerate the de-/hydriding kinetics. For instance, the Mg–Ni–La–Co sample can absorb 3.63 wt% H 2 within 40 min at 343 K. Dehydrogenation analyses demonstrate that the positive effect of MWCNTs is more obvious than that of Co nanoparticles for the experimental samples. The addition of MWCNTs and Co leads to the average dehydrogenation activation energy of experimental samples decreasing to 82.1 and 84.5 kJ mol−1, respectively, indicating a significant decrease of dehydrogenation energy barriers. In addition, analyses of dehydrogenation mechanisms indicate that the rate-limiting steps vary with the addition of MWCTNs and Co nanoparticles. [Display omitted] • Mg-based composites are prepared by in-situ de-/hydriding combined with ball milling. • Composition related de-/hydrogenation behaviors of modified samples are clarified. • The desorption activation energy of Mg–Ni–La-MWCNTs-H reduces to ∼82.1 kJ mol−1. • Desorption rate-limiting steps are proposed by fitting theoretical kinetics models. [ABSTRACT FROM AUTHOR]

This paper presents the results of a multifaceted analysis of the application of catalytic additives to hemp pellets' combustion in a low-power boiler. The research concerns the effects of five catalytic additives applied inside the boiler's combustion chamber—based on TiO2, MnO2, Cu(NO3)2 × 3H2O, H2PtCl6 solution, and 99.5% pure urea solution—on the quality of hemp pellets' combustion process. For this purpose, technical and elemental analyses of the used fuel were performed. The chemical composition of exhaust gases (NOx, CO, SO2, and PM content) was also examined using an exhaust gas analyzer and a dust meter. The highest reductions in emissions of individual pollutants were for CO (−113%; combustion with Ad3), NOx (−66%; combustion with Ad 4), SO2 (−48%; combustion with Ad3), and PM (−78%; combustion with Ad1). The study also determined the amount of avoided costs due to the use of catalytic additives, as well as the annual prevented CO2 emissions to the atmosphere. Due to rising fuel and energy prices, this study could be helpful for biomass boiler owners who would like to burn locally available raw materials and increase the combustion process' efficiency. [ABSTRACT FROM AUTHOR]

The furniture industry is one of the most dynamically developing sectors of the Polish economy. Unfortunately, due to national law, it involves producing a significant amount of wood-based waste, which can only be incinerated in installations that meet the requirements for waste incineration or co-incineration plants. This is due to the presence of various types of chemical additives in post-production residues, which increases the emission of hazardous compounds into the atmosphere during combustion. This article presents an analysis of the impact of the use of catalytic additives on the amount of emissions produced from the combustion of wood-based waste. For this purpose, the analyzed material was pelletized by mixing it with the DESONOX catalyst or by spraying the fuel with the DESONOX + H2O solution in a 1:1 ratio. Catalytic substances were introduced into the fuel until a concentration of 0.1% of its mass was obtained. The use of catalysts has significantly reduced CO and NOX emissions into the atmosphere. In the case of carbon monoxide, the most effective was Ad2 (reduction by 44%), and in the case of nitrogen oxides, Ad1 (reduction by 31%) achieved the best outcome. The results from this analysis may be an indication for Polish legislation encouraging furniture plants to burn this waste in their own units using catalytic substances.

Palladium extraction from chloride solutions with the disulfide of bis(2,4,4-trimethylpentyl)dithiophosphinic acid (L) is reported in this work. The rate of palladium extraction with the disulfide in toluene is slow but it increases in the presence of trioctylamine (TOA). Within 5 min, the degree of palladium recovery (ε) is 99.6%, whereas in the absence of TOA, it is only 19.0% in 10 min. The extraction systems based on the disulfide and TOA mixtures exhibit fast kinetics, high selectivity and can be used for the extraction of palladium from various industrial solutions. [ABSTRACT FROM AUTHOR]

In the paper researches of influence of using catalyst and polar additives on engine performance and emission of exhaust were carried out. The tests were made on diesel engine DuraTorq-TDDi/TDCi 16v with a capacity of 1998cm3 produced by Ford company. Two additives were investigated: FMAX – catalytic additive to fuel and HDOS – polar additive to lubricating oil in different proportions. The results indicated that using tested additives has a positive effect on exhaust composition (lower concentrations of nitrogen oxides, soot and carbon monoxide) and also decreased fuel consumption.

This paper presents the research results of the effect of using calcium oxide and potassium permanganate on the combustion of pellets from wheat bran and beet pulp. The measurements were performed in the technical laboratory of the Centre of Energy Utilization of Non-Traditional Energy Sources in Ostrava. The research examined the effect of the use of chemical substances on the amount of air pollutants from biomass thermal conversion in a low-power boiler and the process temperature. First, we performed technical and elementary analyses of agricultural waste. The raw material was then comminuted, mixed with a selected additive, pelletized, and finally burned in a low-power boiler. The additive was added in three proportions: 1:20, 1:10, and 1:6.67 (i.e., 15%) relative to the fuel weight. The combustion process efficiency was measured using a flue gas analyzer and three thermocouples attached to the data recorder. From the measurement results, we were able to determine the percentage reduction of pollutant emissions into the atmosphere (CO, NOx, and SO2) due to the use of additives. Because emission standards are becoming increasingly stringent and fuel and energy prices are rising, the results presented in this article may be useful to agri-food processing plants that want to manage these materials thermally.

This paper presents the results of a multifaceted analysis of the application of catalytic additives to hemp pellets’ combustion in a low-power boiler. The research concerns the effects of five catalytic additives applied inside the boiler’s combustion chamber—based on TiO2, MnO2, Cu(NO3)2 × 3H2O, H2PtCl6 solution, and 99.5% pure urea solution—on the quality of hemp pellets’ combustion process. For this purpose, technical and elemental analyses of the used fuel were performed. The chemical composition of exhaust gases (NOx, CO, SO2, and PM content) was also examined using an exhaust gas analyzer and a dust meter. The highest reductions in emissions of individual pollutants were for CO (−113%; combustion with Ad3), NOx (−66%; combustion with Ad 4), SO2 (−48%; combustion with Ad3), and PM (−78%; combustion with Ad1). The study also determined the amount of avoided costs due to the use of catalytic additives, as well as the annual prevented CO2 emissions to the atmosphere. Due to rising fuel and energy prices, this study could be helpful for biomass boiler owners who would like to burn locally available raw materials and increase the combustion process’ efficiency.

Structural, electrical, and gas-sensitive characteristics of thin films (~100 nm) of tin dioxide containing Sb, Au, and Ni impurities in the bulk and dispersed Au clusters on the surface were studied. For the films prepared by magnetron sputtering, the size of SnO2 grains is of the order of 40–125 nm, and introduction of Au in the synthesis step leads to the Au segregation in the form of nanosized inclusions of the second phase. The sensors are highly sensitive to H2S in a wide concentration interval, 0.5–100 ppm. Operation of the sensors in the thermo-cycling mode ensures increased response to low H2S concentrations (<5 ppm) in the cooling cycle. The values of the sensor response remained high in long-term tests (180 days and more). [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) have been rapidly synthesized on the surface of low-cost commercial chlorinated polymers (chlorinated polyvinyl chloride, polyvinyl chloride), which contains iron compounds, under the action of a high power ion beam at room temperature. Organic (Fe(C 5 H 5 ) 2 ) and inorganic (FeCl 3 ⋅6H 2 O и Fe(NO 3 ) 3 ·9H 2 O) iron compounds were used as catalytic additions. SEM, TEM and Raman spectroscopy were used to investigate the morphologies and structure of irradiated polymers. CNFs had a most probable diameter in the range 50–90 nm and a maximum length of up to 10 μm. The maximum CNFs growth rate was estimated as 160 μm/μs. A possible growth mechanism for CNFs is discussed. [ABSTRACT FROM AUTHOR]

This work is aimed at elaborating a route for co-modification of acidic and catalytic sites on the surface of nanocrystalline tin oxide with the aim to enhance the sensitivity to ammonia gas. Sulfated tin oxide with controlled amount 0–10 wt.% of SO 4 2− as the acidic modifier was synthesized by wet chemical deposition. It was modified by the catalytic additive of ruthenium oxide (0–5 wt.% Ru). Surface acidity was evaluated by temperature-programmed desorption and in situ infrared spectroscopy of adsorbed ammonia. The concentration of Lewis and Broensted acid sites was strongly dependent on sulfate content. Increasing amount of ruthenium oxide depressed surface acidity of catalytically-modified materials. Sensor response to 2–100 ppm NH 3 in air was measured depending on the materials composition. At Ru-loading lower 0.5 wt.% the sensor signal was detected at temperature 200–300 °C and its value was monotonously dependent on SO 4 2− content. The highest ammonia sensitivity was detected at lower temperature of 140–150 °C for co-functionalized tin oxide with comparable contents of Ru and SO 4 2− (1–3 wt.%). From the sensing tests and in situ infrared spectroscopy data it was deduced that the improved sensing of ammonia gas was provided by equivalent impacts from the processes of target molecules adsorption on sulfate-promoted acid sites and NH 3 oxidation on the catalytic clusters of ruthenium oxide. [ABSTRACT FROM AUTHOR]

Experimental results on the stationary burning rate and solid content in the combustion products of mixed compositions with a chlorine-free oxidizer and an active fuel binder in the pressure range 0.025-6.0 MPa are presented. The effect of catalytic additives (silica and carbon black), the particle size of aluminum powder, and the method of preparing samples for combustion of the mixed compositions under consideration are analyzed. [ABSTRACT FROM AUTHOR]

The effect of two initiators, so-called dual initiators system on atom radical transfer polymerization (ATRP), were studied with dimethyl-2,6-dibromohepanedioate (DMDBHD) and ethyl-2-bromoisobutyrate (EBIB). Cu(I)Br as catalyst and N, N, N′, N′, N′-pentamethyl-diethylenetriamine as ligand were employed for styrene ATRP. Interestingly, bimodal MWD were shown for the dual initiator system, and one of the peaks had higher molecular weight (MW) and the other had lower MW compared to a one-initiator system. The lower MW peak in bimodal peaks seemed to be mainly resulting from EBIB and the higher MW peak from DMDBHD. Furthermore, methylaluminoxane (MAO) was fed into the ATRP reaction to observe the effect of it on ATRP. As the MAO/CuBr molar ratio in feed increased from 0 to 1, the molecular weight and conversion increased without a notable change in PDI and curve shape of GPC. The conversion in the presence of MAO was also increased with the increase in MAO/CuBr molar ratio. The effect of CpTiCl on the ATRP was opposite to that of MAO. As the CpTiCl/CuBr molar ratio increased from 0 to 1, the conversion of polymerization was down from 56 to 35%. Furthermore, the molecular weight was drastically decreased from 10,000 to 5,500, but their PDI did not show a significant change. These results can elucidated by the retarding effect of CpTiCl on the propagation of polymerization. [ABSTRACT FROM AUTHOR]

Ammonia gas detection by pure and catalytically modified WO3-based gas sensors was analyzed. Sensor response of pure tungsten oxide to NH3 was unsatisfactory, probably due to the unselective oxidation of ammonia into NOx. Copper and vanadium were introduced in different concentrations and the resulting material was annealed at different temperatures in order to improve the sensing properties for NH3 detection. The introduction of Cu and V as catalytic additives improved the sensor response to NH3. Possible reaction mechanisms of NH3 over these materials are discussed. Sensor responses to other gases like NO2 or CO and interference of humidity on ammonia detection were also analyzed so as to choose the best sensing element. [ABSTRACT FROM PUBLISHER]

Regeneration studies of spent FCC catalyst were performed in a bench-scale unit under reaction conditions that sufficiently simulate those in the regenerator of the fluid catalytic cracking (FCC) unit. The effect of a conventional Pt-based CO promoter (CP-3®) on the composition of flue gases was examined. As expected addition of CP-3® in the catalytic inventory decreased CO emissions by one order of magnitude, but tripled the NO emissions independently of the concentration of CO promoter used. Addition of a series of Rh-based catalysts modified the composition of flue gases emitted during regeneration. The parameters under study were the catalytic support, the Rh loading on the additive, and the amount of additive used during regeneration. Both a stoichiometric spinel MgO·Al2O3 of high crystallinity and a commercial alumina were competent supports. Promotion of the alumina support with Ce or performing regeneration introducing CO did not affect the additive performance significantly. A combined performance of CO oxidation and NO reduction was achieved minimizing both the Rh loading in the additive (0.1 wt.%) and the concentration of additive used during regeneration (1 wt.%). IR studies suggest that NO reduction by CO over Rh/alumina additives proceeds via the dissociative adsorption of NO, the formation of NCO species on Rh and their migration to the alumina support to finally yield N2 and CO2. [Copyright &y& Elsevier]

Recently, a new seeding growth approach for perovskite thin films is reported to significantly enhance the device performance of perovskite solar cells. This work unveils the intermediate structures and the corresponding growth kinetics during conversion to perovskite crystal thin films assisted by seeding PbS nanocrystals (NCs), using time‐resolved grazing‐incidence X‐ray scattering. Through analyses of time‐resolved crystal formation kinetics obtained from synchrotron X‐rays with a fast subsecond probing time resolution, an important "catalytic" role of the seed‐like PbS NCs is clearly elucidated. The perovskite precursor‐capped PbS NCs are found to not only accelerate the nucleation of a highly oriented intermediate phase, but also catalyze the conversion of the intermediate phase into perovskite crystals with a reduced activation energy Ea = 47 (±5) kJ mol−1, compared to 145 (±38) kJ mol−1 for the pristine perovskite thin film. The reduced Ea is attributed to a designated crystal lattice alignment of the perovskite nanocrystals with perovskite cubic crystals; the pivotal heterointerface alignment of the perovskite crystals coordinated by the Pb NCs leads to an improved film surface morphology with less pinholes and enhanced crystal texture and thermal stability. These together contribute to the significantly improved photovoltaic performance of the corresponding devices. [ABSTRACT FROM AUTHOR]