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There are dire concerns of clean and green energy development with a sustainable economic growth in China. The present study aims to gauge the short term and long term relationship among the real economic output, labor, capital, energy and trade considering global financial crunch of 2008. There are two different models estimated in the production framework with fossil fuels and clean fuels in the economy of China. Specifically, there is indication of a long run association with convergence dynamics among real economic output, labor, capital, fossil fuel and trade before 2008 but not vice versa. The coefficient of fossil fuel with a greater magnitude is indicative of its huge role for higher real output growth, ceteris paribus. Likely, the findings turn out to be significant for real output, labor, capital, clean fuels and trade while long run elasticities corroborate that labor, capital, clean fuels and trade have a positive and significant impact on economic output. The sign and magnitude of the estimate of clean fuels is much higher than before crisis period indicating a paradigm shift in energy mix therein economic output growth. It is recommended that clean fuels should be promoted as their role is non trivial for economic-environmental sustainability in China. • Dynamics among real output, fossil and clean fuels with trade are assessed considering global financial crunch of 2008 • The greater magnitude of fossil fuels is indicative of its pivotal importance in economic output and trade • The magnitude of the clean fuels is threefold than before crisis period indicating a paradigm shift in China's energy mix • Clean fuels is non trivial for economic growth and trade • Clean energy efficiency, financial investments, and green governance required to foster economic-environmental sustainability [ABSTRACT FROM AUTHOR]

Pyrolysis of biomass and organic matter in fluidized bed reactors have become popular in recent years due to the efficient conversion of biomass to bio-fuels. Among others, the presence of mesoscale structures produced by the transient nature of gas solid flow governs the performance of fluidized bed reactors. In the present study, monodispersed system with the particle size of 155 µm and bidispersed system with particle sizes of 128 and 1500 µm are simulated by the multi-fluid model with the kinetic theory of granular flow closure laws. The objective is to investigate the effect of size distribution and solid volume fraction on the hydrodynamics of gas-solid flows. The ANSYS Fluent® software is used for the simulations and the slip velocity, heterogeneity index as well as mixing index are investigated. A two dimensional fully periodic domain is used to investigate the slip velocity at five different solid concentrations in dilute range. The slip velocity, which represents the interaction between solid particles and gas, calculated by simulation is higher than that calculated through Richardson-Zaki's correlation. The mixing index is found to be minimum for a solid volume concentration of 5%. The heterogeneity index is significantly less than 1 for both cases with bidisperesed system having lower value as compared to monodispersed system. The image analysis of solid fraction contours exhibits that mesoscale structures are dense and non-uniform for solid fractions of 0.05 and are small and uniform of solid fractions of 0.025 and 0.075. • Solid particle clusters using Eulerian CFD for bidispersed systems are observed. • H d is for bidisperesed system is much lower than monodispersed system. • Dense, non-uniform clusters are observed for solid fraction of 0.05. • Small, uniform clusters are observed for solid fractions of 0.025 and 0.075. [ABSTRACT FROM AUTHOR]

Due to energy crises and environmental pollution worldwide, researchers have sought efficient electrocatalysts for oxygen evolution reaction (OER) and photocatalysts to eliminate organic pollutants. In the present work, we have synthesized a fullerene-C 60 -based CeO 2 @C 60 core-shell hybrid and characterized it with various state-of-art techniques to explore its OER performance and photocatalytic properties under natural sunlight. TEM nano-graphs and EDX color mapping exhibited the uniform covering of C 60 over CeO 2 forming a core-shell structure with a particle size of 54 nm. The XPS results demonstrate the coexistence of Ce3+ and Ce4+ oxidation states, resulting in the formation of rich oxygen vacancy defects, which induced the efficient charge transformation from CeO 2 to C 60 , enhancing the photocatalytic activity and promoting the OER reaction. The electrochemical measurements revealed a lower overpotential (312 mV) and small Tafel slope (54 mV/dec) at 10 mA/cm2 current density of CeO 2 @C 60 core-shell hybrid than pure CeO 2. Further, the hybrid is stable up to 2000th cycles, and the chronoamperometry test showed that it remains stable for 45 hr without degrading in 1 M KOH solution. The photocatalytic activity under natural sunlight irradiations showed that the CeO 2 @C 60 core-shell hybrid completely degraded P-nitroaniline (P-Nitro) organic pollutant after 75 min, with outstanding recyclability up to the 7th cycle of use. Furthermore, the present work explores the tremendous potential of C 60 and rare earth metal oxide-based hybrid catalysts having exceptional stability toward photocatalysis and electrochemical water splitting. [Display omitted] [ABSTRACT FROM AUTHOR]

Dual metal doping is a state-of-the-art technique for improving the electrocatalytic characteristics for oxygen evolution reaction (OER) and enhancement of the antibacterial activity of the material. Series of rare earth dual metal-doped Pr 2 O 3 electrocatalysts (Pr 2 CeMO 3 , M = Sm, Yb, Er) were successfully fabricated by employing sol-gel treatment. The antimicrobial and electrochemical applications of grown products were studied along with physical properties using advanced techniques such as FESEM, EDX, XRD, FTIR, IV, CV, LSV, EIS, and ECSA. The prepared products retain the monoclinic Pr 2 O 3 structure with the successful doping of rare-earth elements. From the FESEM analysis, grown products have the grainy conglomerate shape, icy monoclinic boxes, irregular lamellar shaped, and well-crystallized grains with the plate-like morphology. EDX has confirmed the presence of metal elements Pr, Ce, Sm, Yb, and Er in grown samples. The electrochemical measurements exhibited the enhancement by dual-doping, and Pr 2 CeSmO 3 has an extraordinarily low overpotential of 189 mV to reach 10 mAcm−2 density and lower Tafel slope (75 mV/dec) for oxygen evolution reaction (OER) in 1.0 M KOH electrolyte. Furthermore, the electrocatalytic efficiency of Pr 2 CeSmO 3 electrocatalyst for OER is extremely long-lasting for (>16 h). The antibacterial test showed that all grown single and dual-doped nanostructures have good antibacterial performance, but Pr 2 CeSmO 3 exhibits strong inhibition activity towards E. coli , K. pneumoniae , S. aureus , and P. vulgaris bacterial strains with maximum inhibition zone diameter 30, 32, 35, and 31 mm, respectively. This low-cost method for the production of rare earth dual metal-doped materials holds a lot of potential for making efficient catalysts, electrochemical energy-conversion devices, and economical antibacterial agents. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles and their composites with conducting polymers, specifically Polyaniline (PANI) were utilized for fabricating nanoscale supercapacitor (SC) electrode materials. In the present study, we have synthesized pristine Pr 2 O 3 , NiO, Co 3 O 4 nanoparticles, binary PANI-Pr 2 O 3 , PANI-NiO, PANI-Co 3 O 4 , ternary Pr 2 O 3 –NiO–Co 3 O 4 , and quaternary PANI-Pr 2 O 3 –NiO–Co 3 O 4 spherical core-shell nanocomposite using co-precipitation and ultra-sonication methods. The grown samples were characterized with different analytical techniques. The XRD pattern revealed that the as-synthesized products were crystalline with Pr 2 O 3 hexagonal phase, NiO cubic phase, and Co 3 O 4 cubic phase in pure and nanocomposites. The Williamson-Hall, Scherrer, and size-strain plot methods were employed to study the crystalline development and contribution of micro-strain. FTIR pattern exhibited the metal-oxygen and PANI bond vibrations. FE-SEM images shown the spherical core-shell shape morphology of quaternary nanocomposite. EDX evident the presence of praseodymium, cobalt, and nickel in synthesized samples. UV–vis spectroscopy confirmed the absorption in the visible region. The IV graphs showed a higher conductivity of quaternary nanocomposite. The cyclic voltammetry results revealed that the quaternary nanocomposite has a higher specific capacitance 500 Fg-1 as compared to binary nanocomposites 134 F g−1 (PANI-Pr 2 O 3), 143 F g−1 (PANI-Co 3 O 4), 256 F g−1 (PANI-NiO), and PANI (90.8 F g−1) at a scan rate of 5 m Vs−1. The GCD results also showed that the quaternary nanocomposite has a higher specific capacitance of 905 F g−1 at current density 1 A g−1 with maximum energy density and power density of 87.99 kWhkg-1 and 2.6 k W kg−1 , respectively. The EIS curve also confirmed that the quaternary nanocomposite has a lower polarization resistance (R p) and solution resistance (R s). The higher capacitance of quaternary nanocomposite can facilitate ion transfer, and the formation of its core-shell structure flourish to enhance surface-dependent electrochemical properties. Furthermore, this study gives a novel research idea to manufacture electrode materials for supercapacitors. [ABSTRACT FROM AUTHOR]

Erbium oxide due to its large polarizability and wide bandgap possesses superior dielectric properties and low leakage current. To study the effect of annealing environments on dielectric properties of erbium oxide, it was annealed under argon and air environments. Complex impedance analysis was performed to investigate dielectric properties, relaxation and conduction processes of the annealed samples. The decrease in grain size and increase in surface area, due to annealing in argon environment, resulted in over 2-fold increase in dielectric constant as compared to conventionally used SiO 2 (Effendy et al., 2017) [1]. The annealing in reducing environment also happened to widen the bandgap energy of erbium oxide. Annealing of erbium oxide in inert environment was proved to be better for the enhancement of dielectric properties, owing to creation of smaller grains with larger grain boundaries. [ABSTRACT FROM AUTHOR]

The current review highlights the complex behavior of thallium (Tl) in soil and plant systems, offering insight into its hazardous characteristics and far-reaching implications. The research investigates the many sources of Tl, from its natural existence in the earth crust to its increased release through anthropogenic activities such as industrial operations and mining. Soil emerges as a significant reservoir of Tl, with diverse physicochemical variables influencing bioavailability and entrance into the food chain, notably in Brassicaceae family members. Additionally, the study highlights a critical knowledge gap concerning Tl influence on legumes (e.g., soybean), underlining the pressing demand for additional studies in this crucial sector. Despite the importance of leguminous crops in the world food supply and soil fertility, the possible impacts of Tl on these crops have received little attention. As we traverse the ecological complexity of Tl, this review advocates the collaborative research efforts to eliminate crucial gaps and provide solutions for reducing Tl detrimental impacts on soil and plant systems. This effort intends to pave the path for sustainable agricultural practices by emphasizing the creation of Tl-tolerant legume varieties and revealing the complicated dynamics of Tl-plant interactions, assuring the long-term durability of our food systems against the danger of Tl toxicity. [Display omitted] • Thallium enhancement in the environment is increasing via industrialization. • Thallium is highly bioaccumulated in edible parts of plant. • Tl(III) are more toxic than Tl(I) for living biota. • Detrimental consequences of Tl on living biota remain elusive. [ABSTRACT FROM AUTHOR]

• Direct dual Z-scheme TiO-WO 3 -CeO 2 heterostructured nanocomposite successfully synthesized by co-precipitation route. • The nanocomposite TiO-WO 3 -CeO 2 showed boosted photocatalytic activity towards different pollutants. • Systematic investigations confirmed the superior charge separation by direct dual Z-scheme. • Enhanced antibacterial activity of nanocomposite against various pathogenic bacterial strain. • The higher super-capacitive behaviour of nanocomposite. [Display omitted] Direct dual Z-scheme heterostructured nanocomposite TiO 2 -WO 3 -CeO 2 (NC) and pristine metal oxides nanostructures (NSs) were fabricated using a facile co-precipitation route. XRD, FTIR, and Raman data have confirmed the formation of NSs and NC. FESEM images showed quasi-mesoporous morphology of as-grown nanocomposite. EDX analysis confirmed the existence of titanium (Ti), cerium (Ce), and tungsten (W) in grown NC. The energy bandgap of NC was narrow 2.45 eV as compared to NSs. The higher electrical conductivity and lower recombination rate of NC were observed in IV and PL analysis. The photodegradation efficiency of NC was recorded 99.8% after 60 min under sunlight radiation against methylene blue (MB), which was significantly higher than NSs. NC catalyst has shown excellent photodegradation against other organic pollutants and has superior recyclability up to 7th cycle toward MB dye with a ~ 6% deficit in photodegradation efficiency. The antimicrobial activity results indicated the higher inhibition ability of NC against E. coli , K. pneumoniae , S. aureus , P. Vulgaris , and P. aeruginosa with maximum inhibition zone diameter 25, 29, 26, 28, and 27 mm, respectively. The electrochemical tests including CV, EIS, and GCD exhibited the superior capacitive behaviour of NC. These results demonstrate that grown NC is an efficient material for electrochemical devices, water purification, and biomedical applications. [ABSTRACT FROM AUTHOR]

Pristine CdO and chromium (Cr)-cobalt (Co) co-doped CdO nanowires via a facile co-precipitation protocol were synthesized and characterized with different analytical techniques to investigate its physical, photocatalytic, antibacterial, and electrochemical properties. The co-doping of Cr-Co into CdO matrix and their structural variations were confirmed by X-ray diffraction (XRD) data. Fourier transform infrared (FTIR) and Raman spectra also confirmed the doping of Cr and Co ions. The energy bandgap was extracted by employing different methods using UV–vis results, exhibited redshift by decreasing Co contents and blue shift by increasing Cr concentration. Scanning electron microscopy (SEM) images confirmed the preparation of nanowires. The photocatalytic and antibacterial experiments results showed the higher photodegradation efficiency against methylene blue (MB) (99.5%), methyl orange (MO) (90.6%), rhodamine-B (RhB) (87.5%), safranin-O (SF) (87.5%), and methyl red (MR) dyes (99.99%), after 60 min of sunlight illumination and the higher zone of inhibition (ZOI) against Klebsiella pneumoniae and Staphylococcus aureus for optimal doped Cd 0.90 Co 0.05 Cr 0.05 O (Cd4) sample. The recyclability tests using Cd4 catalyst were exhibited higher stability up to 5th cycles. The higher ability to decompose dyes and kill bacteria is due to the generation of reactive species, confirmed by the radical trapping experiments. The electrochemical measurements were revealed that the Cd4 sample has a higher specific capacitance of 500 F/ g− 1 at 10 mV/s scan rate, excellent energy density 72 Wh/Kg, and greater power density of 4800 W kg− 1 at a current density of 0.1 A/g. Furthermore, the properties of CdO can be tuned by co-doping for making it a useful material for photocatalyst, supercapacitors electrodes, and antibacterial applications. [Display omitted] • Pristine CdO and Cr-Co co-doped CdO nanowires were synthesized via a facile co-precipitation method. • Different analytical techniques such as XRD, FTIR, Raman, UV–vis, IV, SEM, CV, EIS, and GCD were used. • Enhanced photocatalytic performance against various pollutants with stability upto 5th cycle was achieved. • Improved antibacterial characteristics against different human pathogenic bacterial strain was attained. • The higher specific capacitance, energy density, and power density at optimal loading of Cr and Co were obtained. [ABSTRACT FROM AUTHOR]

In this study, the micro-emulsion approach was adopted to fabricate rare earth (Nd) and transition metal (Cu) co-doped barium hexaferrite (Ba 1-x Nd x Fe 12-y Cu y O 19) nanoparticles (NPs). The fabricated co-doped and undoped materials were characterized by FTIR, XRD, and SEM techniques for structural and morphological investigation. Structural studies such as XRD and FTIR confirmed Nd and Cu doping at the tetrahedral and octahedral sites of barium hexaferrite, respectively. The SEM analysis made sure that the materials were successfully produced at the nanoscale. Dielectric measurements revealed that the dielectric constant and AC conductivity values of the co-doped sample were higher than those of the undoped sample. The VSM study confirms the improved magnetic properties of the sample after co-doping that facilitates its separation and reuse after photocatalytic experiments. The co-doped and undoped sample's photocatalytic activities (PCA) were explored by comparing their Methyl Green (MG) dye degradation efficiencies. The results revealed that the co-doped barium hexaferrite sample degraded almost 92.6% of the MG dye, while the undoped sample degraded just 37.4%. The higher PCA of the co-doped sample is credited to its structural defects, which adjust the band interval to increase electrical conductivity. In addition, the co-doped sample lost only 2% photocatalytic efficiency after five successive cycles, demonstrating its potential for reuse. Application studies have clearly shown that our Nd-Cu co-doped barium hexaferrite sample has a great potential for practical application to remove toxic dyes from the environment. [Display omitted] [ABSTRACT FROM AUTHOR]

Rising consumption and cost of fossil fuels invite the researchers to discover the renewable energy sources. Herein, a novel approach to enhance the photocatalytic performances of rutile-TiO 2 has been revealed. To boost the hydrogen generation reactions, Pd/Rb 2 O cocatalysts have been deposited over TiO 2 via chemical reduction. The morphology and optical characteristics of catalysts were demonstrated by XRD, Raman, UV-Vis/DRS, SEM and TEM analysis. Surface properties, particle sizes, and chemical composition were examined via AFM and XPS techniques. The H 2 production activities were monitored by GC-TCD (Shimadzu-2010/Japan). Comparatively, Pd 1.8 /RbO 0.2 @TiO 2 was found most active catalysts that can deliver hydrogen 22.74 mmolg−1h−1. Higher H 2 generation activities were attributed to the presence of Pd and Rb 2 O cocatalysts. Rb 2 O promoted electrons from TiO 2 to Pd active sites by elevation in fermi energy levels to attain the equilibrium during photoreactions. The mechanistic approach for higher electron transportation and better charge separation has been demonstrated and discussed over here. On the basis of results, it can be concluded that the work reported here in is reliable for sustainable energy applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Fe 3 O 4 could be a better choice as anode for sodium-ion batteries (NIBs) due to high sodium ion storage capability and abundant resource. Yet, the low conductivity and severe volume expansion during cycling have fetched large defies towards practicality. In this work, an ovoid Fe 3 O 4 /rGO and (5%, 10%) cobalt doped Fe 3 O 4 /rGO nanocomposites were synthesized through one-step hydrothermal route. Structural, morphological chemical, vibrational, and compositional analysis have been employed using X-ray diffraction, Scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The results indicate the successful substitution of cationic Co2+ ions in Fe 3 O 4 lattice. Hence, integration of optimal cobalt doping in Fe 3 O 4 lattice can alter the charge/discharge specific capacity as compared to undoped Fe 3 O 4 -rGO anode. Due to sufficient production of oxygen vacancies in the structure 5% Co- Fe 3 O 4 /rGO reveals the highest initial charge capacity of 434 mAh g−1 at 0.05 C and exhibits stable prolonged cycling and delivers upto 303 mAh g−1 of charge capacity during 100 cycles (with 100% of CE and 72% of remaining capacity retention)as compared to 10% Co- Fe 3 O 4 /rGO (414 mAh g−1) and Fe 3 O 4 /rGO (357 mAh g−1) nanocomposite. Moreover, the Nyquist plot reveals the rapid transfer of charge for 5% Co- Fe 3 O 4 /rGO anode due to lowest charge transfer impedance of 56.5 Ω as compared to 10% Co- Fe 3 O 4 /rGO (114.3 Ω) and pristine Fe 3 O 4 /rGO (177.8 Ω). Therefore, the presence of rGO layers and the optimum doping of Co atoms in Fe 3 O 4 crystal can curtail volume expansion, generate more contact sites for electrode/electrolyte, deep penetration of electrolyte into the electrode and can yield superior electrochemical performance via fast Na-ion diffusion rate. Sodium-ion batteries are a promising technology for electric vehicles, the energy grid and other applications. [Display omitted] • Fe 3 O 4 /rGO and (5%, 10%) cobalt doped Fe 3 O 4 /rGO nanocomposites were synthesized through one-step hydrothermal route. • The XRD and XPS results indicate the successful substitution of cationic Co2+ ions in Fe 3 O 4 lattice. • 5% Co- Fe 3 O 4 /rGO reveals the highest initial charge capacity of 434 mAh g−1 at 0.05 C. • The high performance of 5% Co- Fe 3 O 4 /rGO anode was attributed to lowest charge transfer impedance of 56.5 Ω. • The presence of rGO layers and the optimum doping of Co atoms in Fe 3 O 4 crystal can curtail volume expansion. [ABSTRACT FROM AUTHOR]

• The manuscript presents method to characterize solid particle clusters using digital image analysis and Eulerian CFD. • Cluster size increases with the increase in particle dimeter as well as with the increase in initial solid concentration. • 1% concentration shows single peak while 5 & 10% show bimodal cluster distribution. Presence of meso-scale structures such as particle clusters and gas bubbles is ubiquitous in fluidized beds frequently used in pyrolysis of coal and biomass. In recent years, bubbling and circulating fluidized beds have become popular for highly efficient conversion of carbonaceous feedstock into pyrolysis products. The characterization and study of hydrodynamics inside these reactors can provide an insight into the mechanisms controlling the performance of these reactors. Among others, cluster size distribution and mean cluster size are the key parameters defining the hydrodynamics of these reactors. In the current work, Digital Image Analysis (DIA) was applied to computationally obtained instantaneous snapshots during the CFD simulations of gas-solid flows. Transient two fluid modeling (TFM) was applied to three different gas-solid systems in periodic domains with different particulate systems keeping same grid size. The dimensionless axial cluster size was defined in line with literature. The cluster sizes and their distributions are obtained and compared with the available empirical correlations present in the literature based on experimental observations having similar range of operating conditions as well as system characteristics. It is found that the results of current approach agree well with the available data. The methodology followed in current work presents an alternative to expensive experimentation for development of a universal cluster size correlation. [ABSTRACT FROM AUTHOR]