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The composites (SiO2/HATP) were prepared by condensation reflux and high-temperature calcination using natural attapulgite and silica particles, and it was utilized for the adsorption of toluene. The physicochemical properties of the composite adsorbents were characterized using XRD, FT-IR, SEM, and BET techniques. The SiO2/HATP composite material was successfully prepared, with silica particles uniformly loaded onto the surface of ATP. The adsorption performance of the composite materials for toluene was investigated using different feed ratios. The results showed that the composite materials with the mass ratio SiO2/ATP equal to 4 exhibited the highest static adsorption capacity for toluene, reaching 236 mg/g. Additionally, dynamic adsorption performance of toluene was evaluated under conditions of 0 and 80% relative humidity, with corresponding breakthrough times of 90 and 36 min, respectively. The adsorption capacity of the composite materials for toluene was 6–8 times higher than that of pure attapulgite clay. Furthermore, the adsorption mechanisms of the composite materials were investigated through adsorption kinetics, adsorption isotherms, and adsorption thermodynamics. The results indicated that the adsorption of toluene by the composite materials followed a pseudo-first-order kinetic model and Langmuir adsorption isotherm, suggesting a spontaneous exothermic physical adsorption process at a monolayer level. Moreover, regeneration experiments were conducted, and after 5 cycles of adsorption-desorption tests, the composite materials maintained a penetration time of 85 and 30 min for toluene under conditions of 0 and 80% relative humidity, respectively, demonstrating good recyclability. [ABSTRACT FROM AUTHOR]

The rapid development of the battery industry has brought about a large amount of waste battery pollution. How to realize the high-value utilization of waste batteries is an urgent problem to be solved. Herein, cobalt and titanium compounds (LTCO) were firstly recovered from spent lithium-ion batteries (LIBs) using the carbon thermal reduction approach, and plasmonic attapulgite/Co(Ti)Ox (H-ATP/Co(Ti)Ox) nanocomposites were prepared by the microwave hydrothermal technique. H-ATP had a large specific surface area and enough active sites to capture CO2 molecules. The biochar not only reduced the spinel phase of waste LIBs into metal oxides including Co3O4 and TiO2 but also increased the separation and transmission of the carriers, thereby accelerating the adsorption and reduction of CO2. In addition, H-ATP/Co(Ti)Ox exhibited a localized surface plasmon resonance effect (LSPR) in the visible to near-infrared region and released high-energy hot electrons, enhancing the surface temperature of the catalyst and further improving the catalytic reduction of CO2 with a high CO yield of 14.7 μmol·g−1·h−1. The current work demonstrates the potential for CO2 reduction by taking advantage of natural mineral and spent batteries. [ABSTRACT FROM AUTHOR]

The specific surface area of attapulgite was significantly enhanced (from 128 to 212 m2/g) by its purification with sodium hexametaphosphate and nitric acid. Subsequently, an acid modification method was employed to prepare a coated attapulgite cordierite honeycomb with a specific surface area approximately 39 times larger than that of the bare cordierite honeycomb. SEM images showed that the surface of the cordierite was rough and uneven, with the attapulgite filling the large pores on its surface, forming a "nail-like" interaction between the coating and the carrier. After loading the catalyst, no significant mass loss was observed after 1 h of ultrasonic testing, indicating good adhesion stability of the coating. Furthermore, under test conditions of GHSV (Gas Hourly Space Velocity) = 10 000 h–1 and a toluene concentration of 1500 ppm, the prepared integrated catalyst exhibited excellent activity for the catalytic oxidation of toluene, with T50 and T90 values of 261 and 290°C, respectively, suggesting broad application prospects. [ABSTRACT FROM AUTHOR]

It is still a critical challenge to prepare engineering plastics with multi‐functionalities and high‐performances while considering their aesthetic properties and dyeing processes. In this study, a light‐colored conductive nanorod (CNR) was employed to mediate the morphology of immiscible polypropylene/poly(butylene succinate) (PP/PBS) blends. The CNR could be only located in polar PBS phase to effectively control the viscoelasticity ratio between binary phases. By incorporating just 9 per hundred resins (phr) of CNR, the sea‐island structure of PP/PBS (70/30) would transform a stable co‐continuous morphology of PP/PBS/CNR (70/30/9). The addition of CNR led to a significant reduction in blends' surface resistivity and volume resistivity. Simultaneously, the mechanical properties and appearance colors of the ternary blends were improved. The effect of CNR in morphological mediation was further verified with PP/poly(butylene adipate terephthalate)/CNR (PP/PBAT/CNR) and PP/poly(ε‐caprolactone)/CNR (PP/PCL/CNR) blends. In summary, this work provided a desirable engineering plastic, demonstrating permanent antistatic performance, improved mechanical properties and good colorability. [ABSTRACT FROM AUTHOR]

A hydrophobic attapulgite adsorbent was prepared by grafting the hydrophobic modifier triethoxyloctylsilane onto attapulgite as a carrier. The water contact angle, XRD, N2 adsorption and desorption were used to analyze the microstructure of the materials. The results showed that compared with the unmodified attapulgite adsorbent, the modified attapulgite adsorbent greatly reduced the adsorption capacity of water vapor. That is, the adsorption capacity decreases from 339.44 mg/g to 52.27 mg/g, and in the range from 1% to 15% of the modifier concentration, the adsorption capacity of water decreases gradually with the increase of the modifier concentration. The optimal modification time was 10 min and the optimal modification concentration was 1%. The adsorption capacity of xylene before modification is about 5.21 mg/g, the adsorption capacity of water vapor is about 23.06 mg/g. The adsorption capacity of xylene after modification is about 22.93 mg/g, the adsorption capacity of water vapor is about 13.84 mg/g. [ABSTRACT FROM AUTHOR]

Complex pollutants are discharging and accumulating in rivers and oceans, requiring a coupled strategy to resolve pollutants efficiently. A novel method is proposed to treat multiple pollutants with C,N co-doped TiO2 hollow nanofibers coated stainless steel meshes which can realize efficient oil/water separation and visible light-drove dyes photodegradation. The poly(divinylbenzene-co-vinylbenzene chloride), P(DVB-co-VBC), nanofibers are generated by precipitate cationic polymerization on the mesh framework, following with quaternization by triethylamine for N doping. Then, TiO2 is coated on the polymeric nanofibers via in-situ sol–gel process of tetrabutyl titanate. The functional mesh coated with C,N co-doped TiO2 hollow nanofibers is obtained after calcination under nitrogen atmosphere. The resultant mesh demonstrates superhydrophilic/underwater superoleophobic property which is promising in oil/water separation. More importantly, the C,N co-doped TiO2 hollow nanofibers endow the mesh with high photodegradation ability to dyes under visible light. This work draws an affordable but high-performance multifunctional mesh for potential applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

High performance electrochemical energy storage device is an important means to solve the energy problem. As one of the next generation energy storage components, supercapacitor has received more and more attention in recent years. In this work, we synthesized a self-supporting MnCo2O4@Co(OH)2 core–shell heterostructure (CSHs), this can not only enhance the strength of the material, but also generate abundant electron transport pathways. In addition, we also added flaky carbon nitride (g-C3N4) after treatment with nitric acid (HNO3) to improve the cycle stability and specific capacitance of the material. By adjusting the chemical bath (CBD) time, the loading amount of Co(OH)2 nanosheets can be controlled, giving full play to the synergy between the materials, so that the prepared composite has greater specific capacitance, higher rate performance and better cycle stability. When the current density is 0.5 A·g−1, the specific capacitance of the composite is about 1932 F·g−1. In the two electrode system, the energy density is 23.2 Wh·kg−1 at a power density of 600 W·kg−1. At a high current density of 10 A·g−1, after 10,000 cycles, the initial capacitance of the composite material maintained 83.3%. [ABSTRACT FROM AUTHOR]

Nickel aluminum hydrotalcite/clay/activated carbon (LDH/BE/AC) composites were prepared by urea hydrolysis from spent bleaching earth (SBE) to adsorb and remove Chlorotetracycline (CTC), Tetracycline (TC) and Ciprofloxacin (CIP) in aqueous solution. The adsorption method has the advantages of low cost, high efficiency, no secondary pollution and simple and easy operation. A series of performance tests were carried out on the composites. The results show that when the dosage of clay/activated carbon (BE/AC) is 0.2 g, the distribution of LDH/BE/AC on BE/AC is relatively uniform, which is conducive to the adsorption of pollutants. Compared with BE/AC, because the synthesis of LDH/BE/AC occupies the pores on the surface and inside of BE/AC, the specific surface area and pore volume of LDH/BE/AC composites are reduced. But at the same time, the adsorption sites of BE/AC are increased and the adsorption capacity is enhanced. The optimum adsorption capacities of the composites for CTC, TC and CIP are 160.4 mg/g, 122.3 mg/g and 91.3 mg/g respectively, and have good cycle stability. This paper provides an idea for industrial sewage treatment, that is treating waste with waste. [ABSTRACT FROM AUTHOR]

Thiol-functionalized organosilica (OS-SH) was synthesized via an ultra-fast sol–gel procedure without using any templates. The OS-SH was then employed as an adsorbent to remove Hg(II) ions from aqueous solution. Pore structure and material morphology were characterized by FTIR, TGA, SEM, TEM, and N2 sorption measurements. The OS-SH adsorbents demonstrated an outstanding adsorption performance (72.48 mg g–1 at pH 3). The adsorption isotherm can be best described by the Langmuir model, suggesting a monolayer adsorption behavior by chemical mechanism. The adsorption kinetics of Hg(II) on OS‑SH was well fitted by the pseudo-second-order model. The synthesis approach proposed in this study provides a much simple, tender as well as highly efficient way to design functional porous adsorbents for the removal of heavy metal ions. [ABSTRACT FROM AUTHOR]

An efficient heterostructure, compactly durian-like mischcrystal TiO2/graphene containing the anatase and rutile phase, was prepared via a seed-induced synthesis. The TiO2 seed crystal on the surface of graphene plays a vital role in the formation of durian-like mischcrystal TiO2/graphene. The scattered rutile-TiO2 nanoparticles interspersed on the crystal planes of anatase-TiO2 tetrahedron. This novel configuration improved the BET specific surface area to 71.28 m2/g and the visible light response range of multiphase TiO2/graphene. The heterostructure and the synergistic effect between the anatase and rutile TiO2 could transfer the electron, leading to suppress the electron-hole recombination. After 3 h irradiation, the desulfurization rate of durian-like mischcrystal TiO2/graphene photocatalyst reached 83.5% for dibenzothiophene. [ABSTRACT FROM AUTHOR]

A high-efficiency carbon-based metal catalyst was prepared using inexpensive raw materials and a simple synthetic method to replace the commercial platinum-based catalyst in oxygen reduction reaction (ORR). In this article, clay was used as the template, and residual organic matter after oil adsorption was used as the carbon source and the nitrogen source, respectively. Through ion adsorption, nitrogen-doped porous carbon catalyst (Fe3C/NC) modified by iron carbide was synthesized by high-temperature pyrolysis and etching of clay mineral template. Fe3C/NC was characterized by Fourier-transform infrared spectroscopy (FT-IR), High-resolution transmission electron microscopy (TEM) and X-ray diffractometer. Further experiment showed that this catalyst had good electrochemical activity for ORR. In this paper, we use the organic matter in the waste clay as the carbon source and nitrogen source and use the characteristics of clay in the waste clay to introduce iron ions into the reaction. After high-temperature calcination, we get Fe3C/NC composite. Fe-N co-doping can expose more graphite defects and more active sites, which can also improve the electrocatalytic performance of ORR. [ABSTRACT FROM AUTHOR]

Spent bleaching earth (SBE) as an industrious solid rubbish seriously causes the environmental pollution problem. The resourceful utilization of SBE has become increasingly important. In this work, silicon and carbon ingredients derived from SBE were coincidently employed to synthesize a 4A zeolite/carbon composite molecular sieve (4A/CMS). Therein, the graphite carbon components in the form of porous lamellar scattering among the interlayer, surface, and periphery of 4A zeolite promote the rate of mass transfer for the lipophilic gas, which can effectively improve the adsorption property for the volatile organic compounds. The obtained 4A/CMS has large specific surface area, hierarchical pore structure, satisfactory adsorption capacity, and regeneration performance, and its equilibrium adsorption capacity of p-xylene can achieve 209.57 mg·g−1. The pseudo-first-order rate equation is appropriate for the adsorption kinetics. In the end, the formation mechanism of 4A/CMS was illuminated in detail. □ Spent bleaching earth (SBE) as an industrious solid rubbish were utilized resourcefully. Silicon and carbon ingredients from SBE were coincidently employed to synthesize 4A/CMS. Graphitic carbon with hierarchical pore promoted the rate of mass transfer of organic gas. 4A/CMS exhibited excellent adsorption capacity and regeneration performance of p-xylene. [ABSTRACT FROM AUTHOR]

The rational design and synthesis of electrocatalysts for hydrogen evolution reaction (HER) remain great challenges. Herein, cubic RuSe2 (c-RuSe2) electrocatalysts with different 1T phase ratios (ranging from 20.53% to 64.97%) and crystallinities (ranging from 1.72% to 89.10%) were developed by a fast and efficient microwave-assisted synthesis method. Remarkably, the c-RuSe2 calcined at 500 °C (RuSe2-500) with 45.46% 1T phase and 86.75% crystallinity exhibited a small overpotential of 29 mV at 10 mA cm−2 and a Tafel slope of 64 mV dec−1, close to the commercial Pt/C (31 mV, 53 mV dec−1) and better than most of the reported materials. The enhanced performance of RuSe2-500 could be attributed to the crystallinity, and the 1T phase content reached a certain equilibrium at 500 °C. Moreover, RuSe2-500 had the smallest charge transfer resistance, mainly due to its abundant active centers and excellent conductivity brought by the 1T phase, which were in favor of the HER kinetics and catalytic performance. This study explored the relationship between the ratio of the 1T phase and crystallinity in c-RuSe2, and gives a new pathway to improve the activity by synergistic regulation. [ABSTRACT FROM AUTHOR]

High-performance electrochemical energy storage device is an important means to solve the energy problem. As one of the next-generation energy storage components, supercapacitor has received more and more attention in recent years. In this study, MoS2/N-CNTs nanocomposites were synthesized using MoO3 as the template. The ultra-thin MoS2 nanosheets were modified on nitrogen-doped carbon nanotubes. The nanocomposites showed rapid electron transfer efficiency, increased charge storage, and good cycle stability. When the current density is 1 A g−1, the specific capacitance of the composite is about 225 F g−1. In the two-electrode system, the energy density is 9.89 Wh kg−1 at a power density of 699.3 W·kg−1. At a high current density of 10 A g−1, the initial capacitance of the composite material maintained 87% even after 10,000 cycles. [ABSTRACT FROM AUTHOR]

Firstly, Sb‐SnO2/potassium titanate (Sb‐SnO2/ KTO) was fabricated by a sol‐gel method, it was named ECF. and then Cu7S4 nanorod arrays were grown on the surface of ECF by a hydrothermal method (Cu7S4 NW/ECF).This article discusses the preparation method of Cu7S4 NW/ECF composite photocatalyst to solve the problem of degradation of tetracycline hydrochloride under visible light. It is found that Cu7S4 NW/ECF composite materials can be successfully prepared when Cu : S=1 : 1, and the Cu7S4 NW/ECF composite has stronger photocatalytic activity then others, The degradation efficiency of tetracycline hydrochloride (TCH) by the composite can reach 98 % after 2 h. which is mainly attributed to the fact that Cu7S4 is a near‐infrared material, and a tight heterojunction can be formed between Cu7S4 and ECF, which expands the light response range of the material to a certain extent. At the same time, the direct Z‐type mechanism of Cu7S4 NW/ECF composite in the process of photocatalysis is proposed, which is conducive to the separation of electrons and holes. Therefore, the Cu7S4 NW/ECF composite material can effectively degrade tetracycline hydrochloride. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) synthesis is a critical chemical process to develop nitrogen-containing commodities which remains a significant challenge in chemistry and industry. Photocatalysis reduction has been deemed as one of the most promising strategies for N2 fixation under mild conditions. Herein, a series of Pr doped LiNbO3 (Pr3+:LiNbO3) were synthesized by a facile sol–gel method. Results showed that the Pr3+:LiNbO3 upconverted visible light into ultraviolet light and had the highest up-conversion efficiency when the molar ratio of Pr3+ was 2.5 mol%. In addition, the oxygen vacancies generated by the incorporation of Pr3+ into the LiNbO3 crystal lattice acted as active sites boosting the adsorption and activation of N2. The NH4+ production rate reached the highest of 30.72 μmol/L, attributed to the synergistic effects combining spontaneous polarization of the nonlinear optical (NLO) material LiNbO3 and up-conversion luminescence of Pr3+, which not only broaden the adsorption range of solar light but also enhance the charge separation. The up-conversion NLO material Pr3+:LiNbO3 in this study provides a novel alternative for guiding the design of ammonia synthesis photocatalyst. [ABSTRACT FROM AUTHOR]

BE/C-A750-1/1 is prepared by carbonizing SBE and then activating with KOH. BE/C-A750-1/1 has good adsorption capacity for Pb(II), and the adsorption capacity for Pb(II) is 206.65 mg/g. The harmful effects of coexisting cations are listed in ascending order: K+ < Na+ < Mg2+. Adsorption and desorption studies show that the adsorption capacity of BE/C-A750-1/1 for Pb(II) after adsorption and desorption 3 times is 183.62 mg/g. The adsorption mechanism mainly includes electrostatic attraction, ion exchange, physical adsorption, and chemical complexation. This suggests that activated BE/C may be a promising candidate for removing Pb(II) from industrial wastewater. [ABSTRACT FROM AUTHOR]

In this paper, rutile phase titanium oxide/Sb-SnO2/anatase phase titanium oxide (TiO2 (R)/C-TiO2 (A)) heterostructured nanocomposites were prepared by a sol–gel method and a hydrothermal method. By optimizing the mass ratio between TiO2 (R) and C-TiO2 (A), the rod-ball heterostructures of TiO2 (R)/C-TiO2 (A) were formed and exhibited enhanced simulated sunlight-driven photocatalytic desulfurization performance. According to the results, the desulfurization rate of TiO2 (R)/C-TiO2 (A) was 93.98% after 60 min, which is higher than C-TiO2 (A) and TiO2 (R)/TiO2 (A). In addition, the photocatalytic recyclability test indicated that after three times the reuse of TiO2 (R)/C-TiO2 (A) could still reach 85.98%. The enhanced photocatalytic performance could be attributed to the double Z-scheme heterojunction in the TiO2 (R)/C-TiO2 (A) and the uniformly structure of rod array, which resulted in the higher separation efficiency of electrons and holes. Furthermore, the results of photocatalytic active radical species trapping experiments showed that the main substances in the photocatalytic reaction are ∙O2− and h+. This paper also established the double Z-scheme heterojunction reaction mechanism. [ABSTRACT FROM AUTHOR]

Developing photocatalysts with wide spectrum absorption and strong nitrogen activation is critical for nitrogen fixation under mild conditions. Herein, one-dimensional natural clay attapulgite (ATP) supported YF3:Sm3+ were successfully synthesized via microwave hydrothermal method, and the composites were employed as the catalyst for photocatalytic nitrogen fixation under visible-light irradiation. Results indicated that the production of ammonia reached as high as 41.2 mg·L−1 within 3 h when the molar ratio of Sm3+ and the mass fraction of YF3:Sm3+ were optimized. The enhanced fixation performance is mainly due to that the modified ATP fibber with abundant active sites and the doped fluoride with defective vacancy facilitate the adsorption and activation of N2. Furthermore, the upconversion property of YF3:Sm3+ increases the harvesting of visible-light energy, meanwhile the Z-scheme heterostructure built between YF3:Sm3+ and modified ATP inhibits the recombination of charge carriers and retains high redox potentials for N2 reduction. [ABSTRACT FROM AUTHOR]

Defective crystalline semiconductor plays a significant role in photocatalytic nitrogen fixation, however the rapid recombination of photoexcited electron/hole pairs largely reduces the efficiency. Spontaneous polarization of the nonlinear optical (NLO) material has emerged as a promising strategy for addressing the problem. Herein, a defects-rich NLO crystalline LiNbO3 modulated by natural nano-mineral palygorskite (LiNbO3/Pal) has been synthesized via sol–gel method. The intrinsic polarization of LiNbO3/Pal is investigated by second harmonic generation (SHG) measurements, which indicates an intensity of about 3.1 times that of typical NLO material KH2PO4 (KDP). The strong polarization can facilitate the separation of photogenerated charge carriers in the bulk phase and on the surface of LiNbO3/Pal. The existence of oxygen vacancies in LiNbO3/Pal may originate from doping of metal ions and active groups on the surface of Pal during crystallization of LiNbO3, which shortens the bandgap of LiNbO3 and facilitates the absorption and activation of N2 molecules. As a result, the polarization effect and rich oxygen vacancies make the LiNbO3/Pal an exceptional photocatalyst for N2 fixation. The 40 wt% LiNbO3/Pal composite achieves an average rate of photocatalytic NH4+ production of 52.57 μmol gcat−1 h−1 under simulated solar light, which is about sixfold higher than that of bulk LiNbO3. This work not only presents a new perspective on mineral modification of NLO material but also offers a cost-effective photocatalyst for nitrogen fixation. [ABSTRACT FROM AUTHOR]

Photocatalytic fixation of nitrogen has been recognized as a green and promising strategy for ammonia synthesis under ambient conditions. However, the efficient reduction of nitrogen remains a challenge due to high activation energy of nitrogen and low utilization of solar energy. Herein, lanthanum oxyfluoride with different doping content of Pr3+ (LaOF:xPr3+) upconversion nanorods were synthesized by microwave hydrothermal method. Results indicated that the doping of Pr3+ generated considerable defects on the surface of LaOF which acted as the adsorption and activation center for nitrogen. Meanwhile, the Pr3+ ion narrowed the band gap and broadened the light response range of LaOF because LaOF:Pr3+ can upconvert visible light into ultraviolet light, which excite LaOF nanorods and improve the utilization of solar light. The doping amount of Pr3+ had critical effect on the photocatalytic nitrogen fixation performance which reached as high as 180 μmol·L−1·ho1 when the molar ratio of Pr3+ to LaOF was optimized to be 2%. [ABSTRACT FROM AUTHOR]

Ammonia (NH3) obtained by traditional Haber–Bosch technique under extreme conditions stimulates the exploration of sustainable approach via nitrogen photofixation process, however, efficient utilization of solar energy remains a great challenge. Herein, a novel plasmonic W18O49 supported on acid modified attapulgite (H-ATP) composite was prepared by microwave hydrothermal method. The impact of the loading fraction of W18O49 on the ammonia production rate was investigated. Results indicate that ATP possesses abundant adsorption sites after modified by phosphoric acid which facilitates the immobilization of W18O49. The 40% W18O49/H-ATP achieves the highest ammonia production rate of 138.76 μmol g−1 h−1 under solar light irradiation, even 78.76 μmol g−1 h−1 under NIR light (λ > 780 nm). The formed Z-scheme heterostructure improves the separation of charge-carriers, and the localized surface plasmon resonance (LSPR) effect of W18O49 broadens the light response range, both of which contribute to the enhanced nitrogen photofixation performance. [ABSTRACT FROM AUTHOR]

Ammonia synthesis consumes large amounts of energy in traditional industry and causes considerable air pollution to the atmosphere. Therefore, developing green strategies and novel catalysis for NH3 synthesis under ambient conditions using renewable energy is strongly desired. In this work, Er-doped lanthanum cobaltite/attapulgite composites (LaCoO3:Er3+/ATP) were prepared by a sol–gel method. The influence of the Er doping ratio and LaCoO3:Er3+ loading amount on the generation rate of ammonia under visible-light irradiation were investigated. The results show that Er3+-doped LaCoO3 can convert visible light into ultraviolet light and reach the highest conversion rate when the doping amount of the Er element is 6 mol%, which enhances the utilization of solar energy. ATP contributes to the adsorption of N2 and the Co dopant weakens the N≡N bond favoring the activation of N2. Moreover, a direct Z-scheme heterostructure is constructed between LaCoO3:Er3+ and ATP when the loading amount is 10 wt%, which facilitates the separation of charge carriers and preserves the high redox potentials, leading to the enhanced photocatalytic nitrogen fixation performance. Highlights: LaCoO3:Er3+/ATP nanocomposite prepared by sol-gel method. Er3+ doped LaCoO3 convert visible light into ultraviolet light. Co dopant weakens the N≡N bond favoring the activation of N2. Z-scheme LaCoO3:Er3+/ATP enhances the potantial for nitrogen fixation. [ABSTRACT FROM AUTHOR]

Photo-assisted selective catalytic reduction (photo-SCR) has been considered as a promising strategy for NOx removal in recent decades. The purpose of the present work was to test the effectiveness of La1–xPrxCoO3, supported on the surface of natural palygorskite (Pal) by a facile sol-gel method, as a photo-SCR for the removal of NOx from wastewaters. The structure, acidity, and the redox property of the prepared La1–xPrxCoO3/Pal nanocomposite were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Visible diffuse reflectance spectroscopy (UV-Vis DRS), and X-ray photoelectron spectroscopy (XPS). Density functional theory (DFT) calculations were employed to determine the valence bands. The La1–xPrxCoO3/Pal catalysts were then tested for SCR removal of NOx with the assistance of photo-irradiation. The photo-SCR results revealed that the NOx conversion and the N2-selectivity were greatly improved by this method and reached >95% when carried out at the relatively low temperature of 200°C and with the Pr doping at x = 0.5. The improvements were attributed to the co-precipitation of a PrCoO3 phase as in a solid solution forming a coherent heterojunction of PrCoO3/La0.5Pr0.5CoO3 on the Pal surface. [ABSTRACT FROM AUTHOR]

The emission of nitrogen oxides has caused severe harm to the ecosystem; thus, the development of low-cost and high-efficiency denitrification catalysts and new methods are of great significance. In this work, a co-precipitation method was employed to prepare Pr-doped CeO2/attapulgite (CeO2/Pr3+/ATP) nanocomposites. X-ray diffraction (XRD), photoluminance spectroscopy (PL), ultraviolet-visible diffuse reflectance (UV-Vis), Fourier transform infrared (FT-IR), and high-resolution transmission electron microscopy (HRTEM) were utilized to characterize the products. Results showed that the CeO2/Pr3+ nanoparticles were uniformly coated on the surface of ATP and demonstrated outstanding upconversion effect which converted the visible light to ultraviolet light. The upconversion luminescence of CeO2/Pr3+/ATP was strongest when the molar doping amount of Pr was 1 mol%, and the photo-SCR denitrification achieved the highest of 90% conversion and 95% selectivity when the loading amount of CeO2/Pr3+ was 40 wt%. The ATP and CeO2/Pr3+ constructed an indirect Z-type heterojunction structure mediated by oxygen vacancy which benefited the separation of charge carriers and enhanced the reduction-oxidation potentials, both are responsible for the remarkable denitrification performance. [ABSTRACT FROM AUTHOR]

CeO2/black phosphorus (BP) heterostructure nanocomposite was synthesized via a two-step assembly method. The structure and optical property of the prepared composites were characterized by X-ray diffraction, transmission electron microscopy, UV-Vis diffuse reflectance spectroscopy (UV-Vis), Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Photocatalytic degradation of bisphenol A (BPA) in simulated waste water was performed by using CeO2/BP nanocomposite as catalyst. Results indicated that the degradation rate of BPA reached 82.3% within 180 min, which was remarkably improved compared with pure CeO2 and BP due to the formation of indirect Z-scheme heterostructure intermediated by oxygen vacancies originated from CeO2. The unique heterostructure facilitated the charge transfer and preserved the high redox potential leading to improve the photocatalytic degradation performance. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs)/attapulgite (ATP) nanocomposite was prepared by a simple impregnation method. The ATP was initially modified with hydrochloric acid solution, which favored for the combination of CQDs due to the generation of hydroxyl group on the surface. XRD shows the decrease of interplanar spacing of ATP (1 1 0) plane, suggesting that the CQDs are immobilized on the surface of ATP. UV–Vis shows that the absorption peak of modified ATP is apparently red-shifted and the absorbance intensity of CQDs/ATP is higher than others. FT-IR and XPS show that the CQDs are immobilized on the surface of ATP through hydroxylation reaction. TEM shows that the average diameter of CQDs nanoparticles is about 5 nm and they are coated on the surface of ATP uniformly. The CQDs/ATP nanocomposite was employed as catalyst for photocatalytic degradation of dibenzothiophene (DBT) in model gasoline under visible light irradiation. The influence of the mass ratio of CQDs to ATP on desulfurization performance was investigated. The desulfurization rate of DBT could reach 93% when the mass ratio of CQDs/ATP is 3:10. The enhanced photocatalytic oxidative desulfurization was attributed to the sensitizing effect and up-conversion property of CQDs. [ABSTRACT FROM AUTHOR]

LaBO/attapulgite (ATP) (B=Mn, Fe, Co, Ni) composites were prepared by sol-gel method using citric acid as complex agent. The products were characterized by X-ray diffraction transmission electron microscopy, energy-dispersive spectroscopy, Battett-Emmett-Teller, fourier-transform infrared, H temperature-programmed reduction and temperature-programmed desorption of NH measurements. The catalytic activity of LaBO/ATP nanocomposites was evaluated via selective catalytic reduction of NO with NH by fixed bed denitration equipment at low-temperature. The impact of the various B-site elements on the NO conversion was investigated. Results showed that the adsorption capacity of NH played significant role in the low temperature denitrification process, and Mn was the best B-site element where LaMnO/ATP achieves 81% conversion of NO at 250 °C. [ABSTRACT FROM AUTHOR]

In this paper, graphitic carbon nitride (g-CN) was first proposed for the pioneer application of anticorrosion coatings. Original g-CN was facilely treated using HNO and the exfoliated g-CN sheets (E-g-CN) were fabricated, and then, polyaniline/E-g-CN composites (PANI/E-g-CN) as novel anticorrosive media were synthesized by chemical oxidative polymerization and devoted to the corrosion protection of coatings. The E-g-CN sheets and PANI/E-g-CN composites were characterized by X-ray diffraction, Fourier transform infrared, thermogravimetric analysis, and transmission electron microscopy. The anticorrosion properties of the samples prepared were investigated by electrochemical measurements including Tafel plots, electrochemical impedance spectra, and open-circuit potential. Accelerated corrosion tests of iron panels coated by PANI/E-g-CN were performed in 3.5 wt% NaCl solution. Anticorrosive mechanism of PANI/E-g-CN was discussed in detail. PANI/E-g-CN-3 fillers possessed superior corrosion inhibition than individual components on iron coatings, which was due to the synergetic effect of anticorrosion between E-g-CN and PANI. [ABSTRACT FROM AUTHOR]

Graphene-based polyaniline (PANI/RGO), used as conductive filler, was synthesized through a new one-pot emulsion polymerization technology. Graphene dispersion (RGO) was obtained by ultrasonically reducing graphene oxide (GO) in a hot sodium hydroxide solution in the absence of any toxic reductant, such as hydrazine hydrate. Sodium dodecyl benzene sulfonate (SDBS), in which RGO sheets were dispersed, was synthesized using dodecyl benzenesulfonic acid (DBSA) and NaOH. In this RGO/SDBS mixture, polyaniline (PANI), doped with multiple acids (HCl-DBSA), was then uniformly polymerized on the surface of the RGO sheets. The experimental results showed that this reaction improved the dispersion of the RGO in the PANI system, and increased the homogeneous distribution of the formed PANI particles on the RGO surface. The synthesized composite material (PANI/RGO) had good thermal stability, electrical conductivity (about 11.71Scm and water dispersibility. Based on its excellent properties, the PANI/RGO was combined with waterborne epoxy resin to prepare anticorrosion coatings. The corrosion resistance of these coatings was studied using Tafel plots, along with other critical properties tested by the national standards. The results suggested that the surface resistivity of the coatings could be as high as 2.4810 with the addition around 3wt.% of the PANI/RGO meeting good antistatic standards. In addition, the antistatic coatings had outstanding corrosion resistance, as well as tremendous physical and chemical properties. Graphene-based polyaniline (PANI/RGO) nanocomposites were obtained using a new one-pot emulsion polymerization technology. Different amount of PANI/RGO nanocomposites were added to waterborne epoxy resin to prepare anticorrosion coatings and some critical properties were studied. For PANI/RGO composites in epoxy base, the optimum loading was found to be 3 wt%, where the coatings showed outstanding performances. These findings will definitely have direct and important effects on the technological applications in many areas. [ABSTRACT FROM AUTHOR]

The attapulgite/carbon (ATP/C) nanocomposite was successfully prepared by two ecofriendly raw materials (ATP, which is a hydrated magnesium aluminum silicate widespread in nature, and d-xylose, which can be obtained from rice hull, wheat straw, etc.) through a facile one-pot hydrothermal procedure. The synthesis conditions, including reaction time, hydrothermal temperature, and the concentration of d-xylose, were regulated to investigate the morphology, functional groups, and pore properties of ATP/C. Adsorption experiments demonstrated that the obtained ATP/C materials had great potential in treatment of methylene blue from aqueous solution. A possible formation mechanism of ATP/C nanocomposite was proposed by powder X-ray diffraction, TG analysis, and N2 adsorption-desorption study, which revealed that carbon successfully anchored onto ATP by the chemical bond of SiOC. © 2014 American Institute of Chemical Engineers Environ Prog, 34: 437-444, 2015 [ABSTRACT FROM AUTHOR]

Modified palygorskite-polythiophene (MPA-PTh) composites were prepared by chemical oxidative polymerization of palygorskite (PA) nucleartor with thiophene (Th) after the surface modification with γ-(2,3-epoxypropoxy) propytrimethoxysilane (KH-560). The MPA-PTh composites were doped in iodine vapor to create the porous palygorskite-polythiophene (PMPA-PTh) conductive composites. Fourier transform infrared spectra (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption isotherms using the Brunauer-Emmett-Teller method (BET) and electrochemical impedance spectrum (EIS) techniques were applied to characterize the modified PA and the prepared composites. According to FTIR and XPS, the KH-560 was bound to the PA surface and the iodine ion (I3− and I5−) entered the PTh molecular chains. XRD, SEM, TEM, BET, and EIS analysis confirmed that the doping of iodine not only transform the core-shell MPA-PTh into the PMPA-PTh but also improve the electrical conductivity of composites. The PMPA-PTh composites were fabricated that yield a volume resistivity of ∼2.44 × 102 Ω cm and a internal resistances of ∼100 Ω, and their BET surface area, BJH (Barrett-Joiner-Halenda) average pore size and BJH cumulative pore volume were improved in comparison with those of the MPA-PTh composites. SEM images showed that the PMPA-PTh composites could form consecutive space network and the PMPA-PTh composites acrylic coating films had advisable conductivity. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

The interaction of bovine hemoglobin (BHb) with troxerutin was investigated by UV-Vis absorption spectra and fluorescence spectra methods, circular dichroism spectra, and the freeze-fractured TEM methods. Results showed that troxerutin causes the fluorescence quenching of BHb through a static quenching mechanism. The binding constant K and number of binding sites n of troxerutin with BHb were obtained. Positive values of the thermodynamic parameters enthalpy change and entropy change indicate that the interaction between troxerutin and BHb is driven mainly by electrostatic interactions. This shows that the binding is spontaneous at the standard state since the change in the standard Gibbs energy value is negative. The average binding distance between the donor (BHb) and the acceptor (troxerutin) was assessed from the Förster theory. The present study suggests that the thermal stability of BHb is enhanced upon binding with troxerutin. [ABSTRACT FROM AUTHOR]