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The development of new and advanced materials for various environmental and energy applications is a prerequisite for the future. In this research, the removal of hazardous moxifloxacin (MOX) is accomplished by synthesizing new hybrids of MOF-5 i.e., Ni/Mo.S2/MOF-5/GO, Ni.S2/MOF-5/GO, Mo.S2/MOF-5/GO, and Ni/Mo.S2/MOF-5 nanocomposites by using a metal-organic framework (MOF-5) and graphene oxide (GO) as a precursor. The introduction of NixMoxS2 facilitates the unique interfacial charge transfer at the heterojunction, demonstrating a significant improvement in the separation effectiveness of the photochemical electron-hole pairs. To evaluate equilibrium adsorption capacity, time, pH, and concentration of organic pollutants were used as experimental parameters. The adsorption kinetics data reveals pseudo-first-order (R2 = 0.965) kinetics when Ni/Mo.S2/MOF-5/GO photocatalyst was irradiated under light for 90 min against MOX degradation. This led to a narrow energy band gap (2.06 eV in Ni/Mo.S2/MOF-5/GO, compared to 2.30 eV in Ni/Mo.S2/MOF-5), as well as excellent photocatalytic activity in the photodegradation of moxifloxacin (MOX), listed in order: Ni/Mo.S2/MOF-5/GO (95%) > Ni.S2/MOF-5/GO (93%) > Mo.S2/MOF5/GO (90%) > Ni/Mo.S2/MOF-5 (86%) in concentrations up to 2.0 mgL−1, caused by the production of superoxide (O2•−) and hydroxide (OH•) radicals, which encouraged the effective photocatalytic activities of the heterostructure. After five successive tests demonstrating its excellent mechanical stability, the impressive recyclability results for the Ni/Mo.S2/MOF-5/GO revealed only a tiny variation in efficiency from 95% (for the first three runs) to 93% (in the fourth run) and 90% (in the fifth run). These findings show that the heterostructure of Ni/Mo.S2/MOF-5/GO is an effective heterojunction photocatalyst for the quick elimination of moxifloxacin (MOX) from aqueous media.

The worldwide emission of greenhouse gases combined with the lessening of crude oils is passionate about the research on sustainable energy conversion and storage devices. Further, the fast evolution of flexible and wearable opto-electronic systems, superior reliability, and ultra-long cycling lives of energy storage devices are of great importance. The poor kinetics of small reactions involved in next-generation energy devices are the main obstacles. The required electrode materials for these devices are emerging tasks for the betterment of these devices. Currently, single-atom catalysts (SACs) have gained pronounced interest as emerging and potential applicants as electrode materials for fruitful results. Herein, we have discussed the recent design principles for the fabrication of SACs for rechargeable batteries (Metal-air battery (Metal = Zn, Al, Li), Metal-sulfur battery, (Metal = Na, Li) and Metal-CO2 battery (Metal = Zn, Li)) and fuel cells. Then, we have summarized the recent advances in assembling and performance of these batteries using SACs as electrode materials. Finally, we have elucidated the role of SACs to resolve the bottle-neck problems of these next-generation energy storage systems. Following the discussion on short-comings and comprehensive future perspectives.

We summarize the latest progress achieved in precious and non-precious carbon based single-atom catalytic active sites, including Pd, Pt, Ir, Ru, Rh, Au, Fe, Co, Mn, Zn, Sn, and Cu, aiming at facilitating metal-air/O2 batteries, water electrolyzers, and fuel-cells commercialization. Correspondingly, several aspects of the intrinsic catalytic activity, for example, the role of center-metal-atoms, number and type of metal-coordinated atoms, and the surrounding environment of central-metal-atom, are systematically discussed. This review includes two major parts: i) the rational summary of recently reported catalysts, comprising synthesis/identification approaches of active-sites to catalytic performance, and ii) the basic key factors, influencing the performance. Equal emphasis is given to experimental results and theoretical calculations to figure out the structure-function correlation between the active-sites configuration and the intrinsic electrocatalytic performance. A research paradigm is suggested to design advanced single-metal-atom catalysts for fuel cells and metal-air batteries. Regardless of these developments, we highlight some remaining debatable issues that require urgent attention. Finally, we provide a comprehensive perspective on the development and progress of single-metal-atom catalysts for fuel cells and batteries.

Layered double hydroxides (LDH) have potential to catalyze the sluggish oxygen evolution reaction.

In this work, we report a synergism of Co/Na in Co@Na–BiVO4 microstructures to boost the photocatalytic performance of bismuth vanadate (BiVO4) catalysts.

Two-dimensional (2D) nanoflakes of vanadium pentoxide (V2O5) are directly developed on the titanium (Ti) substrate (VO@Ti) as an innovative electrode for pseudocapacitor. The designed VO@Ti electrode offers impressive capacitance of 1520 Fg-1 at 1.5 Ag-1 and superb long-term reliability with a 99% retention over 12000 cycles at 20 Ag-1 based on the merits of highly exposed active sites and improved electrical conductivity.

This article proposes the preparation of promising oxide materials with a broad range of applications as electrolytic materials for solid oxide fuel cells (SOFCs). The oxide materials, namely, samarium-doped ceria Sm0.2Ce0.8O (SDC), gadolinium-doped ceria Gd0.2Ce0.8O (GDC), and calcium-doped ceria Ca0.2Ce0.8O (CDC), were prepared through the conventional combustion method with glycerol as a complexing agent. The thermal behavior of the materials was examined through thermogravimetry-differential scanning calorimetry measurements, and their structural and morphological properties were analyzed via X-ray diffractometry (XRD) and scanning electron microscopy with energy-dispersive X-ray spectroscopy. Fourier transform infrared spectroscopy confirmed the presence of the metal oxide group in the range of 400–1500 cm−1. Two probe methods were used for electrical measurements. The XRD patterns obtained confirmed that the materials have cubic fluorite structures with an average crystallite size in the range of 26.8–44.7 nm. The ionic conductivities of the ceria samples were measured in the temperature between 300 and 700 °C. The samples consistently showed semiconducting behavior, with SDC exhibiting the highest ionic conductivity of 8.32 × 10−3 S/cm. A maximum power density of 265 mW/cm2 was recorded at 650 °C when SDC was used as an electrolyte.

Zeolitic imidazole frameworks (ZIFs) and their derivatives, being an emergent category of adsorbents, are anticipated to adsorb organic dyes from aqueous mediums. Herein, ZIF-67 and Ni-doped ZIF-67...

In the present study, highly water stable polymeric metallo organic composite (PMOC) has been synthesized and incorporated into water solution for selective adsorption study. For elucidation of str...

Fe-N-C-based electrocatalysts have been developed as an encouraging substitute compared to their expensive Pt-containing equivalents for the oxygen reduction reaction (ORR). However, they still face major durability challenges from the in- situ production of Fenton radicals. Therefore, the synthesis of Fe-free ORR catalysts is among the emerging concerns. Herein, we have precisely applied a multistep heating strategy to produce mesoporous N-doped carbon nanostructures with Mn-/Co-Nx dual moieties from mixed-metal zeolitic imidazolate frameworks (ZIFs). It is found that their unique structure, with dual-metallic active sites, not only offers a high electrochemical performance for the ORR (E1/2 = 0.83 V vs reversible hydrogen electrode (RHE) in acid media), but also enhances the operational durability of the catalyst after 20 000 cycles with 97% of retention and very low H2O2 production (

Robust hybrid g-C3N4/ZnO-W/Cox heterojunction composites were synthesized using graphitic carbon nitride (g-C3N4) and ZnO-W nanoparticles (NPs) and different concentrations of Co dopant. The hybrid heterojunction composites were prepared by simple and low-cost coprecipitation methods. The fabricated catalyst was explored and investigated using various characterization techniques such as FTIR, XRD, FESEM and EDX. The surface morphology of the as-prepared hybrid nanocomposites with particle sizes in the range of 15–16 nm was validated by SEM analysis. The elemental composition of the synthesized composites was confirmed by EDS analysis. Photocatalysis using a photon as the sole energy source is considered a challenging approach for organic transformations under ambient conditions. The photocatalytic activity of the heterojunctions was tested by photodegrading methylene blue (MB) dye in the presence of sunlight. The reduced band gap of the heterojunction composite of 3.22–2.28 eV revealed that the incorporation of metal ions played an imperative role in modulating the light absorption range for photocatalytic applications. The as-synthesized g-C3N4/ZnO-W/Co0.010 composite suppressed the charge recombination ability during the photocatalytic degradation of methylene blue (MB) dye. The ternary heterojunction C3N4/ZnO-W/Co0.010 composite showed an impressive photocatalytic performance with 90% degradation of MB under visible light within 90 min of irradiation, compared to the outcomes achieved with the other compositions. Lastly, the synthesized composites showed good recyclability and mechanical stability over five cycles, confirming them as promising photocatalyst options in the future.

Binder-free CoMoO4 hexagonal nanosheets have been directly grown on the surface of conductive carbon fabric cloth (CoMoO4@CFC) as a hybrid electrode material for pseudocapacitors (PCs) with outstanding electrochemical properties. The as-prepared CoMoO4@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 CoMoO4@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 CoMoO4@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.

The electrocatalyzed oxygen and hydrogen evolution reactions (OER/HER) are the key constituents of water splitting toward hydrogen production over electrolysis. The development of stable non-noble nanomaterials as bifunctional OER/HER electrocatalysts is the foremost bottleneck to commercial applications. Herein, the fabrication of Te-modulated FeNiOOH nanocubes (NCs) by a novel tailoring approach is reported, and the doping of Te superbly modulated the local electronic structures of Fe and Ni. The Te/FeNiOOH-NC catalyst displays better mass and electron transfer ability, exposure of plentiful OER/HER edge active centers on the surface, and a modulated electronic structure. Accordingly, the as-made Te/FeNiOOH-NC catalyst reveals robust OER activity (overpotential of 0.22 V@10 mA cm-2) and HER activity (overpotential of 0.167 V@10 mA cm-2) in alkaline media. Considerably, this bifunctional catalyst facilitates a high-performance alkaline water electrolyzer with a cell voltage of 1.65 V at 10 mA cm-2. This strategy opens up a new way for designing and advancing the tellurium dopant nanomaterials for various applications.

It's still an ongoing research challenge to explore non-precious metal-based catalysts for substituting precious metal catalysts during full water electrocatalysis. Herein, we reported the partially oxidized cobalt species in nitrogen-doped carbon nanotubes hierarchical structures to produce dual-functionality towards oxygen/hydrogen evolution reactions. The in situ transformation of carbon nanotubes and well-exposed metal-oxide contributes to mass diffusion and greater electrolyte-accessible surface area. The as-synthesized catalyst displays low overpotentials of 287 mV and 171 mV for oxygen and hydrogen evolution reactions at 10 mA cm−2 of current density with remarkable performance during long-term stability. Furthermore, when employed as cathode and anode, a respectable performance of 1.68 V demonstrated our catalyst as an efficient bifunctional material for conducting water-splitting operation.

To accomplish an efficient and high-performance flexible supercapattery, electrochemically active materials with multicomponent and rational morphological architectures are highly enviable. Herein, we demonstrate dual-morphology-based mesoporous nickel-ferrite nanoparticles embedded in ultra-thin nanosheets (NiFe2O4-NP-NS) grown directly on a carbon cloth (CC) substrate to develop a free-standing electrode (NiFe2O4-NP-NS@CC) for a flexible supercapattery. Owing to the symmetric effects of bimetallic oxides, porosity with a higher surface area and dual morphological impact, the designed electrode conferred significantly enhanced electrochemical performance in aqueous as well as solid-state electrolytes. The binder-free architecture offered an excellent capacity of 965 C g-1 (1608 F g−1) at 5 mV s−1 with high coulombic efficiency and a good capacity retention of 94.20% over 5000 cycles, while the single morphology–based electrode showed only 551 C g−1 (919 F g−1) at 5 mV s−1 with a capacity retention of 90.50% over 5000 cycles under identical conditions. A redox-reaction mechanism is proposed based on ex situ XRD, XPS, and TEM analysis, and it further quantitatively distinguished the pseudocapacitive and diffusion-controlled charge storage proportions of NiFe2O4-NP-NS@CC cathodes in aqueous electrolytes. Additionally, the flexible supercapattery (NiFe2O4-NP-NS@CC//NPC) exhibits an outstanding energy density of 69 W h kg−1 at a power density of 771 W kg−1 with highly flexible features, which exceeds that of supercapacitors. These results present the fabricated device as a promising candidate in the field of energy storage.

Rechargeable zinc-ion batteries (ZIBs) with exceptional theoretical capacity have garnered significant interest in large-scale electrochemical energy storage devices due to their low cost, abundant material, inherent safety, high specific energy, and ecofriendly nature. Metal carbides/nitrides, known as MXenes, have emerged as a large family of 2D transition metal carbides or carbonitrides with excellent properties, e.g., high electrical conductivity, large surface functional groups (e.g., F, O, and OH), low energy barriers for the diffusion of electrolyte ions with wide interlayer spaces. After a decade of effort, significant development has been achieved in the synthesis, properties, and applications of MXenes. Thus, it has opened up various exciting opportunities to construct advanced MXene-based nanostructures for ZIBs with excellent specific energy and power. Herein, this review summarizes the advances across multiple synthesis routes, related properties, morphological and structural characteristics, and chemistries of MXenes for ZIBs. The recent development of MXene-based electrodes is introduced, and electrolytes for ZIBs are elucidated in detail. MXene-based rocking chair ZIBs, strategies to enhance the performance of MXene-based cathodes, suppress the dendrites in MXene-based anodes, and MXene-based flexible ZIBs are pointed out. A rational design and modification of the MXenes as well as the production of composites with metal oxides exhibits promise in solving issues and enhancing the electrochemical performance of ZIBs. Finally, the present challenges and future prospects for MXene-based ZIBs are discussed.

This study presents a comparison among different-bottled drinking water commercially available in Lahore Pakistan. For that, five locally produced drinking water brands and four national brands were selected. Different physical, chemical and microbiological parameters like EC, pH, salinity, TDS, Na+, K+, Ca2+, Mg2+, Cl−, F−, Fe3+, SO42-, NO3-, PO43-, Arsenic (As), total coliforms and faecal coliforms/Escherichia coli were analysed . Results showed that there was a remarkable difference in the quality. Analysed data exposed that EC range was 141–298.3 μS/cm, pH 7.35–7.95, Salinity 0.1 ± 0.02 ppt, turbidity 2.13–2.45 NTU, TDS 85–182 mg/L, sodium 12–71.2 mg/L, potassium 0.1–2.4 mg/L, calcium 16–40 mg/L, mag- 30 magnesium 2.5–35 mg/L, chloride 35–95 mg/L, fluoride 0.29–0.94 mg/L,Iron below detectable limits to 0.17 mg/L, sulphate s 22–120 mg/L, phosphates 0.023–0.17 mg/L, nitrates 0.9–3.6 mg/L and arsenic were 0.0005–0.01 mg/L in these brands of drinking water. The analysed data was compared with the PSQCA, US–EPA and WHO standards. In only one brand of water, the concentration of sodium (71.2 mg/L) and arsenic (0.01 mg/L) was higher than permissible limits. For microbiological contamination brand E (80 colonies/100 mL sample), C (25 colonies/100 mL sample), S (100 colonies/100 mL sample) and K (15 colonies/100 mL sample) were .Some of these water brands examined were deficient in essential minerals like S brand in which Magnesium was only 2.5 mg/L and K and G brands in which calcium was 16 mg/L and 20 mg/L, respectively It was observed that treatment plants having raw water of low TDS 60 or those whose process based on 50% mineral dosing and 50% blending were cost-effective. Data presented in this study are important because it can be considered as baseline data for future.

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 CoNi2S4 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.

To substitute precious metal with non-precious electrocatalysts, that can work efficiently, still remains a great challenge. Herein, we fabricated the series of nitrogen doped carbon (NC) and CoFe-NC core–shell architectures to produce dual-functionality towards oxygen reduction/evolution reactions and ultimately for Zn-air battery. The addition of NC tends to prevent the reduction of Co/Fe nanoparticles during pyrolysis which not only provide improved catalytic sites but also boost the specific surface area, graphitization degree, electron and mass transfer capacity. With distinctive core–shell morphology, the as-synthesized CoFe-NC/NC shows superior OER performance with low overpotential (270 mV) than IrO2 (340 mV) at 10 mA cm−2 and nearly close ORR activity with respect to Pt/C. When fabricated as zinc-air battery application, CoFe-NC/NC shows 58 mW cm−2 higher peak power density than that of air-cathodes made of Pt/C and IrO2. Further, our catalyst shows good durability due to the synergistic effect of Fe/Co and NC shell.

In this paper, the facile synthesis of graphene oxide and MOF based composite material for the demanded adsorption of leading antibiotic is reported. The adsorbent showed good results for removal o...

The trace amount of poisoning species in air, such as SOx and NOx, greatly degrade the performance of zinc-air battery, as they block the active sites of conventional metal containing electrocatalysts. To overcome this challenge, a catalyst with enhanced electrocatalytic properties and good resistance towards the small molecular poisons should be prepared. In this work, we synthesized a P, N dual-doped porous carbon nanospheres (DDPCN), which showed an Eonset and E1/2 of 0.98 V and 0.87 V for ORR reduction in alkaline solution, and a Tafel slop of 72 mV/dec, over-performing all the other metal-free catalysts and comparable with the performance of state-of-the-art Pt/C (20 wt%). Moreover, the E1/2 for DDPCN showed negligible change towards poisoning species; while the E1/2 for Pt/C and typical CoOx/CNTs displayed 10/10 mV and 24/13 mV decay by adding trace amount of SO32−/NO2− into the electrolyte solution. By using DDPCN as the electrocatalyst for zinc-air battery application, the device showed the highest open circuit voltage (1.48 V), the highest power density (224 mW cm−2) and the highest energy density (874 W h kg−1) among all metal-free catalysts, and their performances are even better than the Pt/C catalyst. Moreover, these performances showed negligible influence by the poisoning species for DDPCN based Zn-air battery, while the performances for Pt/C and CoOx/CNTs based Zn-air batteries were greatly deteriorated by the poisoning species up to 25% and 40%.

Engineering the morphology of integral building blocks is a key step in broadening their catalytic activities. In this work, an interesting structure is reported by oriented and directed growth of manganese oxide (Mn3O4) quasi-nanocubes on nitrogen doped mesoporous carbon polyhedrons resulting from zeolite imidazole framework (ZIF-8). The prepared Mn3O4/NCP (Mn3O4 quasi-nanocubes on the surface of N-doped carbon polyhedrons) hybrid catalyst showed activity and durability comparable to Pt/C and higher than nitrogen-doped carbon polyhedrons (NCP) and pure Mn3O4. Further studies indicate that oxygen reduction reaction (ORR) is carried out via a four electron transfer mechanism with very low production of hydrogen peroxide (3%). In this perspective, Mn3O4/NCP is an auspicious nominee as a cathodic catalyst because of inexpensive Mn and good durability. Our synthetic strategy may open a new avenue for material synthesis.

The increasing demands of energy and environmental concerns have motivated researchers to cultivate renewable energy resources for replacing conventional fossil fuels. The modern energy conversion and storage devices required high efficient and stable electrocatalysts to fulfil the market demands. In previous years, we are witness for considerable developments of scientific attention in Metal-organic Frameworks (MOFs) and their derived nanomaterials in electrocatalysis. In current review article, we have discussed the progress of optimistic strategies and approaches for the manufacturing of MOF-derived functional materials and their presentation as electrocatalysts for significant energy related reactions. MOFs functioning as a self-sacrificing template bid different benefits for the preparation of metal nanostructures, metal oxides and carbon-abundant materials promoting through the porous structure, organic functionalities, abundance of metal sites and large surface area. Thorough study for the recent advancement in the MOF-derived materials, metal-coordinated N-doped carbons with single-atom active sites are emerging candidates for future commercial applications. However, there are some tasks that should be addressed, to attain improved, appreciative and controlled structural parameters for catalytic and chemical behavior.

Recent progress in synthetic strategies, analysis techniques, and computational modeling assist researchers to develop more active catalysts including metallic clusters to single-atom active sites (SACs). Metal coordinated N-doped carbons (M-N-C) are the most auspicious, with a large number of atomic sites, markedly performing for a series of electrochemical reactions. This perspective sums up the latest innovative and computational comprehension, while giving credit to earlier/pioneering work in carbonaceous assembly materials towards robust electrocatalytic activity for proton exchange membrane fuel cells via inclusive performance assessment of the oxygen reduction reaction (ORR). M-Nx-Cy are exclusively defined active sites for ORR, so there is a unique possibility to intellectually design the relatively new catalysts with much improved activity, selectivity, and durability. Moreover, some SACs structures provide better performance in fuel cells testing with long-term durability. The efforts to understand the connection in SACs based M-Nx-Cy moieties and how these relate to catalytic ORR performance are also conveyed. Owing to comprehensive practical application in the field, this study has covered very encouraging aspects to the current durability status of M-N-C based catalysts for fuel cells followed by degradation mechanisms such as macro-, microdegradation, catalytic poisoning, and future challenges.

The rapid development of flexible and wearable optoelectronic devices, demanding the superior, reliable, and ultra-long cycling energy storage systems. But poor performances of electrode materials used in energy devices are main obstacles. Recently, single-atom catalysts (SACs) are considered as emerging and potential candidates as electrode materials for battery devices. Herein, we have discussed the recent methods for the fabrication of SACs for rechargeable metal-air batteries, metal-CO