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A convenient and one-step surface modification method was developed to introduce different functional groups on the surface of herringbone type carbon nanofibers (CNFs) by treating with nitric acid solution. The modified CNFs were characterized by various techniques such as X-ray diffraction (XRD), nitrogen adsorption–desorption isotherms (BET), thermo gravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and Fourier transform infrared (FT-IR). The XRD studies revealed intensification of graphitization in CNFs as a function of nitric acid treatment. Similarly, the surface modification of CNFs led to enhance the BET surface area from of 112 to 152 m 2 /g. The XPS investigations indicated the existence of alcoholic (C–OH) and carbonyl (C O) functional groups on the surface of modified CNFs. Moreover, FT-IR studies confirmed the generation of carboxylate, hydroxyl and alcoholic functional groups on the surface of acid-treated CNFs. [ABSTRACT FROM AUTHOR]

[Display omitted] Owing to considerable energy constraints and global warming phenomenon, to find alternative sources of renewable and affordable energy has become a highly prerequisite in this current era. Use of sustainable technologies in this regard for renewable fuel retention applications has become more beneficial in encouraging the broad usage of clean energy. Conjugated microporous polymers (CMPs) are a distinct family of composites, that merge extensive the π-conjugation with microporous structure. The CMPs have been recognized as an essential subclass of porous composites, ever since their development in 2007. The CMPs have been developed with a number of distinct configurations and characteristics, which allows for the versatility of conjugated framework cellular implementations and mesoporous structure. The exploration of CMPs in sustainable fuel devices is crucial for the development of CMP-based composites and their use in sustainability and environmental design. Numerous network developing processes and synthesized building components provide a huge heterogeneity of CMPs with various characteristics and design patterns. As a consequence, CMPs have been employed here for cathode/anode materials for lithium ion batteries (LIBs), sodium/potassium LIBs, supercapacitors, fuel cell electrode for solar cell, hydrogen storage materials, photocatalytic hydrogen and oxygen production reaction (HER, OER), photocatalytic CO 2 reduction and so on. Due to the large surface areas of these composites, the distinctive charge storage mechanisms found in CMPs are explored, and a synopsis of how CMPs might facilitate ultrafast in desirable variety is presented. In addition, an evaluation between CMPs and linear polymers is presented, which provides further assistance for the synthesis of active materials. The most significant shortcomings experienced by CMPs in the domains of energy production have been evaluated, and potential strategies, synthetic process with reactions, physiochemical properties along with morphology have been demonstrated. Thus, this review is intended to be an entertaining and motivating study in the scientific community of the energy storage experts. [ABSTRACT FROM AUTHOR]

Pyrolysis kinetics was carried out for Calligonum polygonoides (C Polygonoides) in an inert atmosphere at three different heating temperatures such as 10, 15, and 20 °C/min using thermogravimetric analysis. Physicochemical properties were studied using bomb calorimeter, elemental analyzer, and Fourier Transform Infrared Spectroscopy. C Polygonoides have a calorific value of 16.33 MJ/kg. Gas chromatography-mass spectrometry was used to identify gases produced during pyrolysis. Thermogravimetric analysis was used to investigate the pyrolysis characteristics of biomass. Activation energy for the three zones of pyrolysis were determined using Kissinger and Ozawa model-free methods. Activation energy calculated for zone L zone [l and zone Ill using Ozawa and Kissinger model was 133.73,164.50,254 KJ/mol and 135.61,165.88, and 253.00 KJ/mol, respectively. Thermodynamic parameters such as enthalpy, entropy, and Gibbs free energy were calculated for the three different zones. Kinetic and thermodynamic study confirmed that C Polygonoides can be used as useful and potential bioenergy feedstock. [ABSTRACT FROM AUTHOR]

A new Na–Si/Ce-500 base catalyst was synthesized for the catalytic trans -esterification of non-edible low cost waste cooking oil (WCO) for profitable biodiesel production. The Na–Si/Ce-500 was successfully fabricated by the combination of stöber, reflux and wet impregnation methods respectively. The catalytic efficiency of Na–Si/Ce-500 catalyst was tested at various calcination temperatures ranges from 300 °C to 700 °C. In addition, the catalyst was evaluated by different instrumental techniques XRD, FESEM, EDX, XPS, BET and FTIR. The maximum biodiesel of 98% was obtained by the catalytic trans -esterification of waste cooking oil at optimum reaction conditions of 1:14 WCO/MeOH molar ratio, 70 °C of reaction temperature, 2.5 wt% of catalyst dosage and 2 h of reaction time. The produced biodiesel was certified by FT-IR and GC-MS. The designed catalyst extended the catalytic performance even after 5th runs. Furthermore, the E-factor and catalyst cost analysis were also investigated in the current study, which offer environmentally friendly and low cost biodiesel production opportunities. Moreover, no leaching of basic species was detected by analyzing the biodiesel sample with atomic absorption spectroscopy (AAS), demonstrating the good stability of the designed catalyst. [Display omitted] • A cost effective Na–Si/Ce-500 catalyst was synthesized. • The designed catalyst has significant reusability upto 5 runs. • Biodiesel yield of 98% was achieved at temperate reaction conditions. • Utilization of waste oil is important in term of environment sustainability. [ABSTRACT FROM AUTHOR]

The anti-oxidant nature of Argon gas prevents the formation of water vapors and oxidation of as produced catalysts. These facts have made it possible to synthesize high quality boron nitride nanotubes via Argon supported thermal chemical vapor deposition at a relatively lower temperature of 900 °C. The synthesized sample is the combination of straight, nearly straight and curve like morphologies of boron nitride nanotubes with diameter in the range of 20–80 nm. Internally, each tube has bamboo like structure whereas the external part has lattice fringes with an interlayer spacing of~0.34 nm. X-ray photoelectron spectroscopy shows B 1s and N 1s peaks at 191.4 and 398.7 eV for hexagonal boron nitride nature of the synthesized nanotubes whereas, the recorded Raman spectrum reports a high intensity peak at 1372 (cm −1 ) that corresponds to E 2g mode of vibration in hexagonal boron nitride. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Na-SiO 2 @TiO 2 catalyst was synthesized by wet impregnation method. • Efficient yield of 98% was achieved under the temperate reaction conditions. • Kinetic plots recommended that the reaction pursue the pseudo 1st order kinetics. • The designed catalyst demonstrated the significant catalytic potency upto 5th run. The novel Na-SiO 2 @TiO 2 heterogeneous base catalyst was designed and successfully applied to the trans -esterification reaction of waste cooking oil for sustainable biodiesel production. The designed catalyst was characterized by SEM, XPS, FT-IR and BET before treatment, illustrated its suitability for the catalytic trans -esterification reaction. Moreover, the influence of reaction temperature, time, catalyst concentration and WCO:MeOH molar ratio on the catalytic activity were also investigated, resultant 98% biodiesel yield was achieved. The reusability test demonstrated that the Na-SiO 2 @TiO 2 catalyst has noticeable catalytic potency up to 5 successive runs. Besides, the kinetics study explains that the reaction is kinetically controlled by pseudo 1st order. The Ea was found to be 21.65 kJ/mol. Similarly, the important thermodynamic parameters such as ΔH#, ΔS# and ΔG# were estimated to be 18.52 kJ.mol−1, −219.17 J.mol−1K−1 and 92.59 kJ.mol−1 respectively. [ABSTRACT FROM AUTHOR]