Functionalizing nanostructured carbon nanofibers (CNFs) with bimetallic phosphides enables the material to become an active electrode for multifunctional applications. A facile electrospinning technique is utilized for the first time to develop NiCoP nanoparticles encapsulated CNFs that are used as an energy storage system of supercapattery, and as an electrocatalyst for oxygen reduction, oxygen evolution, and hydrogen evolution reaction in KOH electrolyte. Evolving from the inclusion of bimetallic phosphide nanoparticles, the NiCoP/CNF electrode unveils superior‐specific capacitance (333 Fg−1 at 2 Ag−1) and rate capability (87%). The fabricated supercapattery device offers a voltage of 1.6 V that supplies a remarkable energy density (36 Wh kg−1) along with an improved power density (4000 W kg−1) and unwavering cyclic stability (25 000 cycles). Meanwhile, the NiCoP/CNF electrode has simultaneously performed well as a multifunctional electrocatalyst for oxygen reduction reaction at a half‐wave potential of 0.82 V versus reversible hydrogen electrode and can attain a current density of 10 mA cm−2 at a very low overpotential of 268 and 130 mV for the oxygen evolution reaction and hydrogen evolution reaction, respectively. Thus, the NiCoP/CNF with all its inimitable electrode properties has profoundly proved its proficiency at handling multifunctional challenges in terms of both storage and conversion.

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A unique multifunctional electrode made of well-defined highly crystalline Ni–P nanoparticles interweaved apiece to form sponge-like structure prepared by the single-step hydrothermal method. The distinct phases of interlinked nanospherical Ni–P compounds (Ni2P, Ni2P/Ni12P5, and Ni12P5) were obtained at 140 °C with different reaction time periods. The Ni2P exhibits supreme specific capacity of 206 mA h g–1 (1354 F g–1) at 5 mA cm–2, which seems to be the highest among the Ni2P reported so far. Biomass-derived activated carbon was prepared as a negative electrode (135 F g–1 at 1 mA cm–2) to fabricate a flexible supercapattery gadget, which delivered remarkable energy density and power density of 42 W h kg–1 and 2856 W kg–1 respectively, at 3 mA cm–2 even after 10000 cycles. The Ni–P coated carbon cloth has shown immense mechanical strength and durability, which was tempting to use for electrocatalytic application. Both oxygen evolution reaction and hydrogen evolution reaction trials resulted in the evolution of an enormous amount of gas bubbles with low overpotentials of 278 and 234 mV to achieve a current density of 10 mA cm–2, respectively. Hence, the dominant Ni–P electrodes were made multifunctional by demonstrating its potential application for efficient appliances.

Evolution of 3D nanostructures is luring a great deal of importance owing to their eccentric structures that create plenty of rooms to grasp massive volume of charges. Here, a distinct multifunctional binder‐free flexible electrode is developed by arrays of flower‐like β‐NiS nanostructures over flexible carbon cloth (β‐NiS@CC) by the in situ hydrothermal method. It unveils an ultimate areal capacity of 1.654 C cm−2 (827 C g−1) at 1 mA cm−2, which seems to be the highest among the reported NiS so far. The fabricated flexible supercapattery gadget delivers a remarkable energy density of 38 µWh cm−2 at a power density of 800 µW cm−2. Due to immense mechanical strength and resilience of 3D flower‐like morphology, it is further exposed as an economical bifunctional electrocatalyst. Both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) exhibit a significant burst of the enormous quantity of gas bubbles at the low overpotentials of 320 and 278 mV, respectively, to achieve a current density of 20 mA cm−2. Further, the developed laboratory scale water electrolyzer offers a low cell voltage of 1.65 V to accomplish a water‐splitting current density of 10 mA cm−2. Henceforth, the multifunctional 3D flower‐like β‐NiS electrode is demonstrated by defining its potential use in real‐world appliances.

oxygen evolution reaction and oxygen reduction reaction (OER and ORR) play important roles in rechargeable zinc-air battery (ZAB), whereas OER and hydrogen evolution reaction (HER) are the core reactions in EWS. [4,5] These electrochemical reactions exhibit sluggish kinetics because they require multistep protoncoupled electron transfers, which increase the overpotentials of the systems, thus causing the losses of considerable energy and long-term electrocatalytic activity. [6][7][8][9] Multifunctional electrocatalysts that efficiently catalyzes diverse electrochemical reactions (OER, HER, and ORR) have recently attracted considerable attention. Multifunctional electrocatalysts can reduce the manufacturing cost of the specific electrocatalysts for various electrochemical systems. The state-of-the-art catalysts such as Pt-based electrocatalysts (ORR and HER), IrO 2 and RuO 2 (OER) could not meet the characteristics of ideal multifunctional electrocatalysts because of high cost, non-abundancy, and non-multifunctional electrocatalytic activity. [10] Moreover, there are limited reports on the strategies for synthesizing multi functional electrocatalysts with intense activity, stability, and selectivity; [11][12][13] and this has necessitated the development of inexpensive, abundant, efficient, and stable multifunctional electrocatalysts to substitute the noble metal-based electrocatalysts.Transition metal oxides (TMOs) have been recently identified as the most promising alternatives to noble metal-based electrocatalysts because of their natural abundance, environmental sustainability, and superior thermal and chemical stabilities under different operating conditions. [14][15][16][17][18] A few promising TMOs exhibit spinel structures, especially cobalt oxide, because Co in its d 7 state with unpaired electrons enhances the activation and polarization of media and the presence of different valences encourage electron transfer during ORR, OER, and HER. Similarly, manganese oxides are inexpensive and abundant materials that promote natural OER in plants, as well as the desired four-electron pathway toward ORR; however, the poor electronic conductivity of manganese oxides limits their electrocatalytic activity. To overcome these limitations, manganese oxide can be combined with cobalt as a co-metal in the spinel structure. Further, increasing the surface area and amounts of Mn 3+ and Mn 2+ can considerably enhance the The integration of energy conversion and storage systems such as electrochemical water splitting (EWS) and rechargeable zinc-air battery (ZAB) is on the vision to provide a sustainable future with green energy resources. Herein, a unique strategy for decorating 3D tetragonal CoMn 2 O 4 on carbon cloth (CMO-U@CC) via a facile one-pot in situ hydrothermal process, is reported. The highly exposed morphology of 3D tetragons enhances the electrocatalytic activity of CMO-U@CC. This is the first demonstration of such a bifunctional activity of CMO-U@CC in an EWS system; it achieves a nominal cell voltage of 1.610 ...

Using sonochemical method, BiPO4 nanocrystals were prepared at different pH conditions (pH-1, 3, 5, 7, 9 & 12) for the possible applications of pseudocapacitor electrodes. The prepared BiPO4 nanocrystals belong to monoclinic structure with P21 space group. The SEM image revealed that the particles changed from irregular coarse shape into rod like structure (pH-1 to 7) which finally collapsed into irregular aggregates (pH-9 to pH-12). The observed spot patterns from SAED inferred the polycrystalline nature of the material. The electrochemical performance of the synthesized BiPO4 in various ultrasound irradiation conditions such as irradiation time (30min, 1h, 2h and 3h) and ultrasonication power (40%, 50%, 60% and 70% of instrumental power) was studied. A maximum specific capacitance of 1052F/g (pH-7 at 2mV/s) was observed for the BiPO4 prepared in the ultrasonication reaction condition of 2h with 60% power. Also the obtained specific capacitance was high compared with the conventional precipitation method (623F/g at 2mV/s) that revealed the prominence of sonication method. Similarly, BiPO4 prepared at pH-7 delivered a maximum specific capacitance of 302F/g at 2mA/cm(2) calculated from galvanostatic charge-discharge (GCD) method than the other pH conditions. However, the cycling stability of BiPO4 (pH-7) was not appreciable even for 200 cycles. So, attempts were taken to enhance the cycling stability of the material by employing various carbon matrices such as acetylene black, activated carbon and MWCNT instead of carbon black during electrode preparation. BiPO4 material with activated carbon delivered good capacitance retention compared with other carbon matrices. This enhanced electrochemical performance of BiPO4 (pH-7) using activated carbon matrix inferred that it could be utilized as efficient negative electrode material for pseudocapacitors.

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Since carbon dots (CDs) exhibit excellent biocompatibility, low cytotoxicity, near-infrared (NIR) absorbance, and superior photostability, many types of CDs are considered as powerful candidates for photothermal therapy (PTT) applications. However,...