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It's crucial to fabricate commercial-level electrodes with high mass loading of active materials for supercapacitors (SCs) to address the growing need for commercial-level flexible energy storage devices. In this work, we reported the direct growth of ZnCo 2 O 4 nanonest-like structure composed of nanowires with high mass loading (5 mg cm−2) on the substrate of carbon cloth (CC, hereafter denoted as ZnCo 2 O 4 @CC) via a simple hydrothermal method. The ZnCo 2 O 4 @CC electrode was characterized by a variety of techniques including SEM/TEM, XRD/XPS, and BET/BJH. The ZnCo 2 O 4 @CC electrode possesses a holey characteristic with various electroactive sites for the utilization of electrolyte and delivered high specific capacitance of 1467 (1320 C g-1) Fg−1 at 1.2 Ag-1 with outstanding cycling retention of 95% at 12 Ag-1 and high Coulombic efficiency after 10,000 cycles. In addition, we employed power's law to explore the charge storage kinetics of ZnCo 2 O 4 @CC electrode to investigate the capacitive and diffusion-controlled charge storage quantification. The ZnCo 2 O 4 @CC electrode displayed high capacitive storage properties (42% capacitive at 15 mVs−1). Thus, the admirable electrochemical performance of the ZnCo 2 O 4 electrode highlights the potential application in supercapacitors for future endowers. The ZnCo 2 O 4 @CC electrode possesses a holey characteristic with various electroactive sites for the fully utilization of electrolyte and delivered excellent rate-capability and exceptional cycling stability. [Display omitted] • ZnCo 2 O 4 @CC electrode composed by nanowires synthesized via a simple hydrothermal method for supercapacitor's electrode. • Binder-free ZnCo 2 O 4 @CC electrode exhibits excellent specific capacitance of 1467 (1320 C g-1) Fg−1 at 1.2 Ag-1. • The ZnCo 2 O 4 @CC electrode delivered high capacitance retention of 95% after 10,000 cycles. • The ZnCo 2 O 4 @CC electrode possesses hybrid-kind of charge storage properties. [ABSTRACT FROM AUTHOR]

Binder-free CoMoO 4 hexagonal nanosheets have been directly grown on the surface of conductive carbon fabric cloth (CoMoO 4 @CFC) as a hybrid electrode material for pseudocapacitors (PCs) with outstanding electrochemical properties. The as-prepared CoMoO 4 @CFC sample was structurally and morphologically characterized using various techniques. Microstructure analysis reveals that the hexagonal like 2D structure possesses mesoporous characteristics with abundant electroactive sites as a charge storage host. The CoMoO 4 @CFC was evaluated as a positive electrode material for pseudocapacitors, which revealed a maximum specific capacitance of 1210 F/g at 2.5 A/g with exceptional rate capability and outstanding cycling stability of 91% after 10,000 charge/discharge cycles. The 2D mesoporous hexagonal-like structure provides improved electrolyte movement during charging/discharging process and additional active sites for redox reactions. In addition, the charge storage quantification of diffusion and capacitive charge mechanism was determined by employing Power's law, and accordingly, the CoMoO 4 @CFC electrode was attributed to a high capacitive charge value of (80% at rate 2.5 mV/s). Thus, this work specifies simple and cost-effective method to fabricate pseudocapacitors electrode materials with high energy density and improved cyclic life for energy storage devices. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) have proven remarkable interest in portable digital devices because of their long life span and high power densities. However, low energy densities of SCs hindered their applications due to the lack of high-performance negative electrode materials. In this work, we demonstrated the successful surface engineering of iron oxide nanoparticles (Fe 3 O 4 -NPs) by polyaniline (PANI) coating through a facile low-temperature hydrothermal method. The polyaniline coated iron oxide nanoparticles (Fe 3 O 4 /PANI-NPs) were characterized by a series of techniques including XRD, FT-IR, RAMAN, XPS, TGA, BET, SEM, and TEM. Fe 3 O 4 -NPs and Fe 3 O 4 /PANI-NPs are investigated as negative electrode materials for SCs in basic potassium hydroxide (KOH) electrolyte. The Fe 3 O 4 /PANI-NPs sample possesses specific capacitance of 1669.18 F g−1 while Fe 3 O 4 -NPs exhibits 1351.13 F g−1 at 1 A g−1 at identical conditions. The Fe 3 O 4 /PANI-NPs sample exhibits remarkable electrochemical cycling performance (96.5%) over pristine Fe 3 O 4 -NPs (92%) at high current density of 15 A g−1 by exceeding the 25,000 times charge/discharge cycles. The PANI coating not only offers a strong shell to avoid degradation of the material but also contributes to enhancing the capacitance with outstanding stability. Furthermore, we analyzed the charge storage contributions by implementing the power's law and interestingly Fe 3 O 4 /PANI-NPs sample exhibits high capacitive type storage (85% capacitive at 10 mVs−1). Based on our experiments, Fe 3 O 4 /PANI-NPs shows exceptional high electrochemical results in basic electrolyte with excellent stability and surpass most of recently reported work based on the iron oxides and their composites. Therefore, the proposed strategy can be applied to fabricate the high-performance negative electrode materials for supercapacitors. The Fe 3 O 4 /PANI-NPs electrode showed excellent electrochemical performance with outstanding cycling stability. Image 1 • Engineering the surface of Fe 3 O 4 -NPs by polyaniline coating. • Fe 3 O 4 /PANI-NPs supported on carbon cloth exhibit exceptional high charge storage. • Fe 3 O 4 /PANI-NPs displayed high capacitance of 1669.18 F g-1 at 1 A g-1. • Fe 3 O 4 /PANI-NPs electrode shows excellent cycling stability >95% over 25,000 cycles. [ABSTRACT FROM AUTHOR]

In this work, iron oxide (Fe 3 O 4) nanodiscs and anchored on reduced graphene oxide (rGO) as a nanocomposite (Fe 3 O 4 /rGO) have been fabricated through a surface, scalable hydrothermal process. The morphological and structural studies of Fe 3 O 4 /rGO nanodiscs are analyzed by various techniques such as XRD, XPS, SEM, TEM, and TGA, etc. The Fe 3 O 4 /rGO electrode is tested as a negative electrode in a basic potassium hydroxide (KOH) electrolyte using a three-electrode system for supercapacitor applications. The optimized electrochemical properties of Fe 3 O 4 /rGO are systematically compared with bare Fe 3 O 4 and it is found that the rGO greatly enhanced its performance as a negative electrode. The Fe 3 O 4 /rGO nanodiscs demonstrated a notably high-specific capacitance of 1149 F/g at 1.5 A/g better than that of Fe 3 O 4 nanodiscs (920 F/g at 1.5 A/g). Furthermore, the Fe 3 O 4 /rGO displays the superior cyclic stability of 97.53% after running continuous 10000 GCD cycles at a high current density of 10 A/g, while bare Fe 3 O 4 attained 87.82% at identical conditions. The fascinating electrochemical performance can be benefited for future fabrications of iron graphene-based negative electrode material for SCs. Image 1 • Fe 3 O 4 /rGO nanodiscs composite was prepared through the superficial hydrothermal method. • The use of rGO significantly enhances the properties of Fe 3 O 4 nanodiscs. • Fe 3 O 4 /rGO nanodiscs composite as a negative electrode is promising for electrochemical energy storage. • The Fe 3 O 4 /rGO composite exhibit a specific capacitance of 1149 F/g at 1.5 A/g. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) have been considered as inspiring energy storage devices due to the long cycle lifetime and high power densities. However, their energy density is limited due to the low capacitance of cathode materials and inferior cycling stability at practically useable potential windows >1.2 V. In this paper, we demonstrate the synthesis of a novel ternary Fe 3 O 4 -rGO-MoO 3 nano-composite (FGM) with nanoparticles-like morphology (NPs) by utilizing the fast and facile microwave hydrothermal process. The optimized composition of FGM nanocomposite is characterized by the XPS, EDS, Raman, SEM, TEM and HRTEM techniques. The FGM-NPs supported on the carbon cloth (FGM@CC) electrode is used to investigate the electrochemical charge storage properties in basic potassium hydroxide (KOH) electrolyte. The charge-storage properties of the FGM@CC electrode were studied by the CV, GCD and EIS techniques. The obtained results of FGM@CC electrode in aqueous electrolyte showed excellent electrochemical performance as compared with single metal oxides: maximum specific capacitance of 1666.50 F g−1 (FGM@CC), 1075.26 F g−1 (Fe 3 O 4 NPs) and 952.38 F g−1 (MoO 3 NPs) at a current density of 2.5 A g−1. The capacitance retention was 95.01% (FGM@CC), 94.1% (Fe 3 O 4 NPs) and 92.5% (MoO 3 NPs) after 5000 cycles. Further, the charge storage mechanism is analyzed in the light of power's law and systematical investigated the capacitive and diffusion controlled based stored charge in FGM@CC electrode. Thus FGM nano-composite showed best performance as the cathode material for the next generation flexible supercapacitors. The FGM@CC electrode showed excellent electrochemical performance with as high as C sp of 1666.50 F g−1 at 2.5 A g−1. The FGM@CC electrode possesses 55% of stored energy from surface capacitive storage process and 45% from diffusion controlled process. Image 1 • A ternary Fe3O4-rGO-MoO3 nano-composite is synthesized through a facile microwave strategy. • FGM supported on carbon cloth electrode (FGM@CC) exhibits exceptional high charge storage performance. • FGM@CC electrode reached at high potential window of 1.2 V in aqueous electrolyte. • FGM@CC electrode shows excellent cycling stability >95%. [ABSTRACT FROM AUTHOR]

It is imperative to develop new and efficient electrode materials intended for electrochemical energy storage to accomplish increasing energy demand. Ternary cobalt-nickel-sulfides have gained more attention for energy storage owing to their superior redox chemistry and higher electronic conductivity as electrode materials. Herein, distinctive flower-like CoNi 2 S 4 nanoneedle arrays (CNS–NAs) have been efficiently synthesized on Ni-foam by a very simple hydrothermal method for superior supercapacitors (SCs) electrode performances. The formation of CNS–NAs was depended upon an anion-exchange reaction mechanism relating to the pseudo-Kirkendall effect. The morphology, structure, and physical/chemical properties of the resulting material were analyzed by SEM, TEM/HRTEM, BET, XRD, and XPS. The electrochemical performances in the three-electrode system were evaluated by CV, GCD, and EIS measurements. The as-synthesized CNS–NAs exhibited a higher specific capacitance value of 2300 F/g at a current density of 1 mA/g and excellent cyclic stability with 93.8% capacitive retention after 5000 charge-discharge cycles. Larger surface area, outstanding electrical conductivity, abundant active cites, and distinctive flower-like morphology with the outstanding structural stability of CNS–NAs could be the reasons for its significant effect on the charge transfer and storage which consequences the superior electrochemical performances. In brief, this work offers a cost-effective and facile method to synthesize a promising electrode material for the potential application of high-performance SCs. [ABSTRACT FROM AUTHOR]

Massive advancements in the energy storage devices has urged scientist to remediate physically/chemically electroactive methods for excellent supercapacitor applications. The use of binders in energy storing devices obstacles their charge carrier in redox kinetics and high internal resistances results in low electrochemical performances. Herein, we successfully decorated gravel-like NiMoO 4 nanoparticles arrays onto a carbon cloth (NMO@CC) which is used as binder-free electrode for electrochemical supercapacitor measurements. The NMO@CC electrode unveils a noticeable specific capacitance of 970 F/g 2.5 A/g of current density, exceptional stability and retention of 91.34% after 5000 cycles. The outstanding electrochemical properties of NMO@CC are credited to the conductive nature of double-metal (Ni–Mo) ions and binder-free electrode that facilities rapid redox reactions and designate it as a promising pseudocapacitor in industrial applications. [ABSTRACT FROM AUTHOR]

Ground motion prediction equations (GMPEs) are cornerstone of Probabilistic Seismic Hazard Assessment. A big pool of GMPEs is available nowadays for active crustal and subduction zone categories which are derived from dataset of different regions including the database of Middle East, Europe (non-NGA) and NGA WEST 2 database. For countries like Pakistan which do not have local GMPEs, selection of GMPE is difficult and is merely based on hit and trial. A Comparative analysis of latest set of GMPEs for these respective categories on seismic hazard of Pakistan is unknown. In this study, Probabilistic Seismic Hazard analysis is conducted on urban centers (Gwadar and Quetta) of Balochistan province, a sample from Pakistan is given their potential to become economic hubs as rapid infrastructure development is expected in the region. The analysis is based on area source approach along with the modelling of major active crustal faults of the region. Three sets of GMPEs are selected where first set consists of GMPEs developed by NGA WEST 2, the second set consists of non-NGA based GMPEs while the third set is a hybrid set in which NGA WEST 2 and non-NGA based GMPEs are used together. Logic tree method is employed in this work to take into consideration of the epistemic uncertainty in different GMPEs for each tectonic zone and the seismic source models as well. For 10% probability of exceedance in 50 years (return period 475 years), updated hazard maps for PGA and spectral acceleration for structural period of 0.1 s, 0.2 s, and 1 s are created. These results can be effectively used to reduce seismic risk, to develop effective disaster mitigation, and management strategies. • To conduct the Probabilistic Seismic Hazard analysis of urban centers (Gwadar and Quetta) of Baluchistan province, Pakistan. • To study the effect of latest set of GMPEs for active crustal and subduction zones, on seismic hazard of Pakistan. • To create an updated hazard maps for PGA and spectral acceleration, for 10 and 2% probability of exceedance in 50 years. [ABSTRACT FROM AUTHOR]

Ensemble multi-satellite precipitation datasets (ESPDs) are alternative to satellite-based precipitation products (SPs), which tend to reduce the errors, combine advantages of individual SPs, and have higher accuracy for hydrological applications. The current study proposes and evaluates a dynamic WALS-ESPD developed using the Weighted Average Least Square (WALS) algorithm, which has 0.25° spatial and daily temporal resolutions across glacial, humid, arid and hyper-arid regions of Pakistan during 2000–2015. WALS-ESPD is developed using three SPs, Tropical Rainfall Measurement Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA) 3B42V7, Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks–Climate Data Record (PERSIANN-CDR), Climate Prediction Center MORPHing technique (CMORPH), and one re-analysis product, Era-Interim. Mean Bias (MB), Mean Absolute Error (MAE), unbiased Root Mean Square Error (ubRMSE), Correlation Coefficient (R), Kling-Gupta efficiency (KGE score), and Theil's U are used to evaluate the performance of WALS-ESPD both spatially and temporally. Moreover, the skill scores of statistical metrics are used to assess the WALS-ESPD performance against two previously developed ESPDs, DBMA-ESPD and DCBA-ESPD. TMPA dominated all SPs with average weights of 0.317, 0.341, 0.314, and 0.326 across the glacial, humid, arid and hyper-arid regions. TMPA dominated pre-monsoon (30.26%) and monsoon (35.82%) seasons, while PERSIANN-CDR dominated post-monsoon (27.58%) and winter (29.82%) seasons. WALS-ESPD performed relatively poor across the glacial and humid regions, and during monsoon and pre-monsoon seasons. Skill scores of WALS-ESPD against DBMA-ESPD show better performance of WALS-ESPD in all four regions, especially across the glacial region with the maximum MB, MAE, and ubRMSE scores of 27.36%, 28.34%, and 27.67%, respectively. Meanwhile, WALS-ESPD performed better than DCBA-ESPD in the whole glacial region and most part of other regions, while DCBA-ESPD dominated WALS-ESPD at few stations across humid, arid, and hyper-arid (south-east) regions. • An ensemble satellite-based precipitation dataset (ESPD) is developed using WALS. • The study region covers whole Pakistan with complex topography and diverse climate. • WALS-ESPD significantly reduced the uncertainties across Pakistan. • WALS-ESPD is theoretically and practically superior to traditional DBMA-ESPD. • WALS-ESPD is superior to DCBA-ESPD in most part of the study region. [ABSTRACT FROM AUTHOR]

Developing Ce, La, or Y based rare earth (RE) permanent magnets is a practical way to balance the utilization of RE resources. In this work, Y substitution for Ce and La is found to not only enhance the hard magnetic properties, but also significantly increase the Curie temperature T c and thermal stability of the melt-spun (Ce 0.7 La 0.3) 2 Fe 14 B alloys. To further optimize the magnetic performance, the RE-rich alloy with [(Ce 0.7 La 0.3) 0.8 Y 0.2 17 Fe 78 B 6 composition has been prepared. The good combination of magnetic properties with maximum energy product (BH) max = 7.1 MGOe, intrinsic coercivity H cj = 357 kA/m, and remanent polarization J r = 0.70 T has been obtained, together with low temperature coefficients of remanence (α = −0.255%/K) and coercivity (β = −0.246%/K). Importantly, RE element segregation has been confirmed in RE-rich (Ce,La,Y)–Fe–B alloys by microstructure and composition analysis. La prefers to enter into the intergranular phase than Ce and Y prefers to remain in the hard magnetic main phase, which results in increased T c , improved magnetic properties, and enhanced thermal stability. • A new high-abundance Ce/La/Y-based permanent magnets have been developed. • A good combination of magnetic properties can be obtained in (Ce,La,Y)–Fe–B alloys. • RE element segregation has been confirmed in RE-rich (Ce,La,Y)–Fe–B alloys. • La element prefers to enter into the intergranular phase than Ce element. • Y element likes to remain in the hard magnetic 2:14:1 phase. [ABSTRACT FROM AUTHOR]

Aqueous symmetrical supercapacitors (ASSCs) are offering the safest and cost-effective solution to fulfill the ever-increasing demand for high-performance energy storage devices. However, the narrow operational voltage window in basic electrolytes is significantly limits their practical applications. Herein, we demonstrate a high-voltage ASSCs in a basic electrolyte by combining the binder-free highly Faradic-type cobalt and highly capacitive-type molybdenum oxides with rich oxidation/reduction states. The electrochemical performance of mesoporous cobalt-molybdenum oxide supported on carbon cloth (Co–Mo–O@CC) are first optimized in three electrode-system and it reveals high-capacitance of 1437.5 F g−1 (862.5 C g−1) at 1.5 A g−1 with outstanding rate-capability (81.19%) and cycling stability (95%) over 8000 cycles. Moreover, the fabricated ASSC based on the Co–Mo–O@CC electrodes (CMO||CMO-ASSC) is delivered admirable performance by exhibiting the high-capacitance of 180.5 F g−1 (2.63 F cm−2) at 1.0 A g−1 with good rate capability of 72.34% at high current density of 8 A g−1 as well as decent capacitance retention of 91.80% after 15000 cycles. The CMO||CMO-ASSC displayed a high energy density of 40.77 Wh kg−1 at a high-power density of 894.24 W kg−1 (based on the mass of active materials), which is the best value among ASSCs reported previously. Furthermore, the two CMO||CMO-ASSC coupled in series can charge up to 2.4 V and power two red color light-emitting-diodes (LEDs), demonstrating its practical applications as energy storage devices. Thus, this work paves a novel way to develop high-voltage ASSCs with large energy density and super long life energy storage devices. The CMO||CMO-ASSC displayed a high energy density of 40.77 Wh kg−1 at a high-power density of 894.24 Wh kg−1 (based on the mass of active materials), which is the best among the ASSCs reported previously. The two CMO||CMO-ASSC coupled in series can charge up to 2.4 V and power two red color light-emitting-diodes (LEDs), demonstrating its practical applications as energy storage devices. Image 1 • The binder-free cobalt molybdenum oxide (Co-Mo-O@CC) flowers are synthesized by eco-friendly method. • The Co-Mo-O@CC revealed high-capacitance with outstanding rate-capability and cycling stability over 8000 cycles. • The CMO||CMO-ASSC displayed a high energy density of 40.77 Wh kg−1 at a high-power density of 894.24 Wh kg−1. • Two CMO||CMO-ASSC coupled in series can charge up to 2.4 V and power two red color light-emitting-diodes. [ABSTRACT FROM AUTHOR]