Search

Mechanism of SO 2 effect on Cu 1-x Fe x CeZr catalysts for simultaneous removal of NO and toluene. [Display omitted] • The correlativity between the the reaction process and sulfur poisoning was studied. • The mechanism effect of SO 2 on the reaction process was studied. • A mechanism for simultaneous removal of NO and toluene was proposed. • The introduction of Fe enhanced oxygen vacancies formation and oxygen mobility. Developing non-vanadium-based SCR catalysts with high performances for simultaneous removal of NO and toluene at low-medium temperatures remains a challenge in addressing SO 2 poisoning. Herein, porous Fe-modified CuCeZr catalysts prepared via KIT-6 hard-templating method was conducted to investigate the simultaneous removal of NO and toluene at low-medium temperatures. A suite of experiments and characterizations was systematically used to probe into the effect of SO 2 on the reaction process. The results indicated that porous Fe-modified CuCeZr displayed excellent performance for simultaneous removal of NO and toluene. The introduction of Fe into CuCeZr enhances both acid sites and redox properties via the redox cycle between Cu2++Ce3+↔Cu++Ce4+ and Fe3++Ce3+↔Fe2++Ce4+ redox cycle. Importantly, Fe incorporation leads to the formation of lattice defects and oxygen vacancies, generating abundant active sites that mitigate the detrimental effects of SO 2 poisoning, and promote the efficient removal of NO and toluene simultaneously. Besides, a mechanism influence of SO 2 on the reaction process for simultaneous removal of NO and toluene at low-medium temperatures was proposed. This mechanism has the potential to provide an effective solution for developing non-vanadium-based SCR catalysts with sulfur resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • The interaction mechanism between ions and carbon nanotubes was studied theoretically, and a novel PU/EMIM:TFSI gel with excellent ion transport ability was prepared. • Based on the PU/EMIM:TFSI gel, a multilayer infrared camouflage device was developed, whose regulation coefficient reaches 0.85. • The infrared camouflage devices were further integrated into an array device with 4 rows and 4 columns, and a wireless control system was constructed to realize remote intelligent infrared camouflage. The dynamic regulation of infrared signals has received widespread attention. For the typical multilayer adaptive infrared camouflage structure, many efforts have been made to explore a variety of materials; metals, carbon nanomaterials and polymers can all be used in this field. However, little attention has been given to the mechanism of mass transfer within the structure, which could play a decisive role in the infrared camouflage performance. In this paper, the influence of cation and anion enrichment on the band structure and density of states of multiwalled carbon nanotubes (MWCNTs) is discussed through density functional theory (DFT), and the results show that ion migration plays an important role in the regulation of the emissivity. On the basis of theoretical research, a novel waterborne polyurethane (WPU)/ionic liquid (IL) gel is further prepared to realize control of the ionic transport capability, and a MWCNT film-based sandwich structure is fabricated to achieve adaptive infrared camouflage. The maximum emissivity regulation coefficient reaches 0.85, which is the highest to the best of our knowledge. The optimization scheme proposed in this work can provide a good reference for other similar problems. [ABSTRACT FROM AUTHOR]

A reduction-type S-scheme photocatalyst with bifunctional ability shows efficient and stable activity for simultaneous water purification and H 2 production. [Display omitted] • The stepwise fabrication well preserves the microsphere morphology of Zn 3 In 2 S 6. • The in situ growth of In 2 S 3 on Zn 3 In 2 S 6 shows an efficient construction of S-scheme heterojunction. • The photogenerated holes and electrons are simultaneously utilized for pollutant degradation and H 2 production. • The engineered In 2 S 3 /Zn 3 In 2 S 6 photocatalyst displays an enhanced photocatalytic performance. S-scheme In 2 S 3 /Zn 3 In 2 S 6 microspheres were successfully prepared through hydrothermal means for enhanced photocatalytic H 2 evolution with simultaneous photodegradation of bisphenol A. The microspheres were assembled by embedding 2D In 2 S 3 nanosheets into 2D-3D Zn 3 In 2 S 6 hierarchical microspheres to enhance visible light absorption and separation/migration of photo-excited charge carriers. In bisphenol A aqueous solution, the photocatalytic H 2 evolution rate on In 2 S 3 /Zn 3 In 2 S 6 shows 15.7 and 7.9-folds improvements against that of the individual In 2 S 3 and Zn 3 In 2 S 6. Meanwhile, the degradation efficiency of bisphenol A is up to 95.8 %. The S-scheme charge transfer mechanism in In 2 S 3 /Zn 3 In 2 S 6 microspheres maximizes exerting the redox capability of Zn 3 In 2 S 6 for H 2 evolution and In 2 S 3 for bisphenol A degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel gold nanoparticles (Au NPs)-modified graphdiyne/carbon cloth (Au NPs/GDY/CC) was prepared successfully by electrodeposition. • The unique triangular pore structure in the GDY plane enables more stable anchoring of Au NPs. • The synergistic effect between Au NPs and GDY in Au NPs/GDY/CC complex material significantly enhanced the SERS signal. As a new kind of 2D carbon allotrope, graphdiyne (GDY) has the characteristics of uniform pores and large specific surface area due to its unique electronic space arrangement structure. Therefore, we fabricated a novel gold nanoparticles (Au NPs)/GDY/carbon cloth (CC) SERS substrate by a simple electrodeposition process using GDY nanowall wrapping the CC as support. The effects of electrodeposition conditions on the microstructure and SERS activity of Au NPs/GDY/CC substrate were studied. Under the condition of optimizing deposition time and deposition voltage, the prepared Au NPs/GDY/CC substrate can detect 10-13 M with rhodamine 6G (R6G) as a probe molecule. The maximum enhancement factor (EF) is 2.2 × 1012, and the concentration of R6G is logarithmically correlated with the intensity of the SERS band with a linear correlation coefficient (R2) of 0.97036. These indicate that the Au NPs/GDY/CC substrate has good sensitivity. The prepared Au NPs/GDY/CC SERS substrate was applied to the detection of organic dyes of malachite green (MG) and methyl violet (MV) in water, and the detection limits of both can reach 10-9 M. This highly sensitive and high-performance SERS substrate has broad application prospects in the detection of organic dyes. [ABSTRACT FROM AUTHOR]

Hazardous pentachloronitrobenzene was turned into functional in-situ N-doped alkynyl carbon material with high supercapacitor performance through a green mechanochemical strategy. [Display omitted] • Hazardous PCNB was turned into functional NACM via mechanochemical reaction with CaC 2. • The solvent-free mechanochemical degradation for PCNB is efficient, feasible, and green. • The resultant NACM features alkynyl-linked benzene ring skeleton with multilayered nanoribbon morphology and in-situ N/O doping. • The NACM exhibits high supercapacitor performance. • This work provides an innovative perspective for the current environment and energy problems. Pentachloronitrobenzene (PCNB) as a typical banned POPs has received wide attention for its toxicity, migration and degradation, but its resource utilization has rarely been studied. In this work, hazardous PCNB was efficiently degraded and converted into N-doped alkynyl carbon material (NACM) through a solvent-free mechanochemical strategy. The reaction is mainly due to the substitution reaction of alkynyl groups from CaC 2 to organic chlorines in PCNB through mechanochemical activation. This process is environmentally friendly for its high efficiency, mild operating conditions (ball-milling 60 min under 400 rpm at CaC 2 :PCNB = 10), and superior technological feasibility and economy. The resulting NACM is an unique advanced carbon material with alkynyl-linked benzene ring skeleton, multilayered nanoribbon morphology and in-situ N/O doping, which makes it an excellent electrode material with high specific capacitance (292.9 F cm−3), good electrical conductivity (1718 S m−1), and outstanding cycling stability (>98.1% after 5000 cycles). This work provides a multi-in-one strategy for the PCNB degradation and functional ACMs synthesis, which may be viable for the treatment of other halogenated hazardous chemicals. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel rapid thermal shock method was adopted to achieve the fast preparation of nitrogen-doped graphene film within 10 s. • The NG film prepared through rapid thermal shock method has a high content of nitrogen element, among which the content of graphite nitrogen reaches more than 60%. • Thanks to the presence of numerous graphite nitrogen in NG, the electrical conductivity and the Seebeck coeffience of NG films improve a lot. Meanwhile, the introduction of N element also causes the thermal conductivity of the NG film to decline precipitatingly, according to the calculation results of desity function theory. • A novel temperature sensor was fabricated based the NG film, it is found that the device has good accuracy at both room temperature and high temperature (more than 600 ℃), and shows excellent sensitivity temperature changes. Graphene is restricted by its zero-band gap when applying in functional components. However, its band structure can be adjusted appropriately through nitrogen doping. At present, many nitrogen doping processes have been developed such as chemical vapor deposition, thermal annealing and plasma sputtering, but in general these methods are time-consuming and difficult to control the type of nitrogen atom doped. In this work, an in situ high-temperature thermal shock process, with an extremely fast rate of temperature change of more than 104 K/s, is developed and used to prepare the nitrogen doped graphene (NG) films. This novel N-doped process enables the preparation of NG films within 10 s, which is the fastest to the best of our knowledge. Moreover, the type and content of doped nitrogen atoms can be effectively regulated by controlling the composition of precursor films. Optimally, the nitrogen content of NG film reaches 2.26 %, and the proportion of graphite nitrogen is more than 60 %. The electrical conductivity and the average Seebeck coefficient of the NG film are 13,870 S·m−1 and −46.5 μV/K, respectively. Its thermoelectric power factor reaches 30 μW·m−1·K−1, indicating that the NG film has a good prospect of functional application. Furtherly, A NG film-based temperature reading device is developed, which shows ultra-high accuracy and sensitivity in temperature reading within a rather wide temperature range. [ABSTRACT FROM AUTHOR]

[Display omitted] • A possible mechanism for the simultaneous oxidation of NO and toluene was proposed. • A-site partial substitution with Co can tune the structural properties of La 1-x Co x FeO 3. • The poisoning effects of H 2 O on the performance was studied. • The Interplay between toluene oxidation and NO oxidation were explored. To provide insight into optimizing flue gas treatment, the reaction mechanism for simultaneous oxidation of NO and toluene with H 2 O using a A-site substituted La 1-x Co x FeO 3 (x = 0–0.4) catalysts with three-dimensional porous structure was investigated. The results demonstrated that the partial substitution of La in porous LaFeO 3 by Co can induce the structural distortion, promote the specific surface area, enhance more active site exposure and produce abundant reactive oxygen species, including lattice oxygen with higher mobility, more surface adsorbed oxygen as well as oxygen vacancies, which improved the catalytic activities remarkably. Besides, NO and toluene have mutual promoted effects in the reaction system. The inhibition effect of H 2 O on simultaneous oxidation of NO and toluene was confirmed in that H 2 O consumes the chemisorbed active oxygen atoms. Without H 2 O, absorbed NO reacts with chemisorbed oxygen to form NO 2 , and absorbed toluene is oxidized by lattice oxygen to generate intermediate species which finally completely oxidized into CO 2 and H 2 O. With H 2 O, H 2 O react with chemisorbed oxygen to produce OH species that occupied active sites for toluene adsorption. NO interacts with OH species to form stable nitrate species, which offsets the inhibitive effect of H 2 O on NO oxidation due to the consumption of chemisorbed oxygen. [ABSTRACT FROM AUTHOR]