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This study outlines an effective method for improving the electrochemical properties of MoO 3 by tuning the electronic spin state of Mo via Ni doping, which can enhance its reactivity and weaken the diffusion energy barrier between Zn2+ and MoO 3. [Display omitted] • The electron spin states of Mo are modulated via Ni-ion doping. • The storage mechanism of this electron spin states tuning strategy is clarified. • The assembled Ni-MoO 3 //Zn can afford a high capacity of 258 mAh g −1 at 1 A/g. Aqueous zinc-ion batteries (AZIBs) have received considerable potential for their affordability and high reliability. Among potential cathodes, α-MoO 3 stands out due to its layered structure aligned with the (0 1 0) plane, offering extensive ionic insertion channels for enhanced charge storage. However, its limited electrochemical activity and poor Zn2+ transport kinetics present significant challenges for its deployment in energy storage devices. To overcome these limitations, we introduce a new strategy by doping α-MoO 3 with Ni (Ni-MoO 3), tuning the electron spin states of Mo. Thus modification can activate the reactivity of Ni-MoO 3 towards Zn2+ storage and weaken the interaction between Ni-MoO 3 and intercalated Zn2+, thereby accelerating the Zn2+ transport and storage. Consequently, the electrochemical properties of Ni-MoO 3 significantly surpass those of pure MoO 3 , demonstrating a specific capacity of 258 mAh g−1 at 1 A g−1 and outstanding rate performance (120 mAh g−1 at 10 A g−1). After 1000 cycles at 8 A g−1, it retains 76 % of the initial capacity, with an energy density of 154.4 Wh kg−1 and a power density of 11.2 kW kg−1. This work proves that the modulation of electron spin states in cathode materials via metal ion doping can effectively boost their capacity and cycling durability. [ABSTRACT FROM AUTHOR]

Aqueous Zn-ion hybrid supercapacitors (AZHSCs) combining the advantages of high‐energy batteries and high‐power supercapacitors see a bright future, but they still suffer from the poor capacity of carbonic cathodes. Herein, a functionalized porous carbon cloth (denoted as FPCC) electrode is demonstrated based on commercial carbon cloth (denoted as CC) tuning by structural and surface engineering. The constructed exfoliated porous carbon layer and the negatively charged functionalized interface not only increase the electrical double layer capacitance but also favor the chemical adsorption of Zn2+ to obtain additional pseudocapacitance. Consequently, the FPCC electrode delivers a high capacity of 0.16 mAh cm−2 at 4 mA cm−2, which is 923.8 times higher than CC, and a long cycle life (85.0% capacity retention after 30 000 cycles). More importantly, the Zn//FPCC AZHSC possesses an impressive energy density (3.3 mWh cm−3) and power density (240 mW cm−3), superior to many advanced batteries and supercapacitors. The quasi-solid-state device is also assembled as a demo. This modification strategy may provide new opportunities for high-performance AZHSCs. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) are emerging as one of the most reliable energy storage technologies for scale‐up applications, but still suffer from the instability of Zn anode, which is mainly caused by the undesirable dendrite growth and side reactions. To tackle these issues, we formulate a new aqueous electrolyte with weak solvation effect by introducing low‐dielectric‐constant acetone to achieve H2O‐poor solvation structure of Zn2+. Experimental and theoretical calculation studies concurrently reveal that such solvation structure can: i) relieve the solvated H2O related side reactions, ii) suppress the dendrite growth by boosting the desolvation kinetics of Zn2+ and iii) in situ form solid electrolyte interface (SEI) to synergistically inhibit the side reaction and dendrite growth. The synergy of these three factors prolongs the cycling life of Cu/Zn asymmetric cell from 30 h to more than 800 h at 1 mA cm−2/1 mAh cm−2, and can work at more harsh condition of 5 mA cm−2/5 mAh cm−2. More encouragingly, Zn/V2O5 ⋅ nH2O full cell also shows enhanced cycling stability of 95.9 % capacity retention after 1000 cycles, much better than that with baseline electrolyte (failing at ≈700th cycle). [ABSTRACT FROM AUTHOR]

Aqueous zinc‐ion batteries (AZIBs) are emerging as one of the most reliable energy storage technologies for scale‐up applications, but still suffer from the instability of Zn anode, which is mainly caused by the undesirable dendrite growth and side reactions. To tackle these issues, we formulate a new aqueous electrolyte with weak solvation effect by introducing low‐dielectric‐constant acetone to achieve H2O‐poor solvation structure of Zn2+. Experimental and theoretical calculation studies concurrently reveal that such solvation structure can: i) relieve the solvated H2O related side reactions, ii) suppress the dendrite growth by boosting the desolvation kinetics of Zn2+ and iii) in situ form solid electrolyte interface (SEI) to synergistically inhibit the side reaction and dendrite growth. The synergy of these three factors prolongs the cycling life of Cu/Zn asymmetric cell from 30 h to more than 800 h at 1 mA cm−2/1 mAh cm−2, and can work at more harsh condition of 5 mA cm−2/5 mAh cm−2. More encouragingly, Zn/V2O5 ⋅ nH2O full cell also shows enhanced cycling stability of 95.9 % capacity retention after 1000 cycles, much better than that with baseline electrolyte (failing at ≈700th cycle). [ABSTRACT FROM AUTHOR]

Recently, ruthenium telluride (RuTe 2) has received widespread attention as an effective HER catalyst. In this work, ultrafine and well-dispersed RuTe 2 nanoparticles anchored on nitrogen and boron co-doped graphene (RuTe 2 /BNG) was developed by freeze-drying and facile pyrolysis method, demonstrating a brilliant HER performance. The overpotential of RuTe 2 /BNG at the current density of 10 mA cm−2 is only 34 and 16 mV in 0.5 M H 2 SO 4 and 1.0 M KOH solution, respectively. More importantly, the RuTe 2 /BNG can also maintain significantly robust HER stability during long-term chronopotentiometry measurements. The outstanding HER activity of RuTe 2 /BNG should be ascribed to its properties with abundant defects, large specific surface area, high electronic conductivity and short mass transfer path. Our work offers a new path to fabricate efficient HER catalysts by homogeneously anchoring RuTe 2 on B, N co-doped graphene. [Display omitted] • Ultrafine RuTe 2 nanoparticles anchored on B, N co-doped graphene (RuTe 2 /BNG) was developed by facile pyrolysis method. • The TEM result manifests that the average diameter of RuTe 2 nanoparticles in RuTe 2 /BNG is about 2.6 nm. • The RuTe 2 /BNG catalyst exhibits an outstanding HER activity and stability in both acid and alkaline media. • The influences of the B or N doping on the structure, chemical state and HER activity of catalysts were investigated. [ABSTRACT FROM AUTHOR]

Herein, we present a new and available Ti doping and surface self-passivation strategy to significantly boost the PEC performance of the Fe 2 O 3 nanorods for both solar water splitting and formaldehyde (HCHO) oxidation. Upon Ti doping and surface passivation with KOH treatment, the self-passived Ti 4+ doped Fe 2 O 3 nanorods exhibit substantially higher PEC performance compared to the pristine Fe 2 O 3 and Ti 4+ doped Fe 2 O 3 nanorods, achieving a remarkable photocurrent of 3.7 mA cm −2 at 1.5 V vs. RHE. Furthermore, these self-passived Ti 4+ doped Fe 2 O 3 nanorods also show a 100 mV cathodic shift in onset potential than that of Ti 4+ doped Fe 2 O 3 nanorods and excellent durability. Such the substantially improved photoelectrochemical performance is ascribed to the dramatically increased donor densities and reduced electron-hole recommendation as a result of Ti doping and surface passivation layer that formed after KOH treatment. [ABSTRACT FROM AUTHOR]

A novel method of preparing cube-like MnO 2 by MnCO 3 was firstly reported. The MnCO 3 used as self-sacrificing template was synthesized via a polyol process. The porous, hierarchical MnO 2 microcubes with uniform size were obtained after thermal treatment from as-prepared MnCO 3 in air atmosphere. X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) together recorded the composition and structure information. Electrochemical tests showed that the highest specific capacitance can reach up to 152 F g −1 and hardly any loss was observed after 100 cycles at different current densities. The results suggested that this well-designed material may have a promising application in energy storage of supercapacitor. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) is an important reaction in many energy conversion systems, but it is severely restricted by its slow kinetics. Developing efficient non-noble-metal catalysts for ORR has attracted extended interests, but still remains a great challenge. Herein, an efficient catalysts consisting of Co3O4@Co nanoparticles embedded in N-rich mesoporous carbon matrix is developed by the carbonization of Co-containing zeolitic imidazolate framework precursor. The derived matrix exhibits outstanding catalytic activity with onset potential of 0.97 V vs. RHE, half-wave potential of 0.88 V vs. RHE, and good catalytic durability when tested with the rotation speed of 1600 rpm. Carbinization under NH3 introduces extra elemental N, which subsequently enhances the limiting current densities. This study provides insight into the rational design of highly active ORR catalysts. [ABSTRACT FROM AUTHOR]

Free-standing porous MoO2 nanowires with extraordinary capacitive performance are developed as high-performance electrodes for electrochemical capacitors. The as-obtained MoO2 electrode exhibits a remarkable capacitance of 424.4 mF cm−2 with excellent electrochemical durability (no capacitance decay after 10 000 cycles at various scan rates). [ABSTRACT FROM AUTHOR]

Abstract: In this study, aligned Nd(OH)3 nanobelts with abundant mesopores are successfully assembled by a facile, and template-free electrochemical method. The well-defined porous structure in Nd(OH)3 nanobelts leads to its superior adsorption and the remove rate of Congo red contained in wastewater reach to 99.1% in 30min. [ABSTRACT FROM AUTHOR]

Free-standing CeO2nanorods with different morphology grew directly on Ti substrates viaan electrochemical assembly process, and their absorption edges show a remarkable red-shift to the visible region. Moreover, photoelectrochemical cell (PEC) measurements demonstrate these CeO2nanorods exhibit a photovoltaic response under visible light illumination (λ≥ 390 nm). [ABSTRACT FROM AUTHOR]

Direct ethanol fuel cells (DEFCs) provide a portable and environmentally friendly power source with high energy density. However, the slow kinetic of the ethanol oxidation reaction (EOR) has hindered the commercialization of DEFCs. Palladium (Pd)-based nanomaterials are the best promising catalysts for EOR due to the high catalytic activities and relatively abundant reserves. In this paper, we developed a simple and green way for the preparation of palladium hydride (PdH 0.43) and Au/PdH 0.43 heterostructures. Ethylene glycol (EG) provided the source of H atoms for the formation of PdH 0.43 in synthesis process. The as-synthesized PdH 0.43 and Au/PdH 0.43 nanocrystals were extremely stable under ambient conditions and annealing at 300 °C under Ar. Compared with PdH 0.43 and commercial Pd/C, Au/PdH 0.43 presented a higher mass activity of 2659 mA mg−1, a lower oxidation peak potential, and a higher catalytic stability for oxidizing ethanol. Remarkably, the improved catalytic performance might arise from the synergistically modulation of electronic structure, the enhanced resistance to poisoning products and the acceleration of electron transfer by the formation of palladium hydrides and abundant heterostructures of Au/PdH 0.43. This work provides a promising reference for the development of metal-hydride nanomaterials and heterostructures as efficient catalysts. • The PdH 0.43 and Au/PdH 0.43 were prepared with ethylene glycol as the H source. • The PdH 0.43 and Au/PdH 0.43 were extremely stable in the air over six months. • Au/PdH 0.43 can maintain the stability of structure even annealing at 300 °C in Ar. • Au/PdH 0.43 exhibited a higher performance toward EOR than PdH 0.43 and Pd/C. • The improved activities might arise from the doping of H and heterostructures. [ABSTRACT FROM AUTHOR]

The inferior capacity and cyclic durability of V2O5 caused by inadequate active sites and sluggish kinetics are the main problems to encumber the widespread industrial applications of vanadium‐zinc batteries (VZBs). Herein, a cooperative redox chemistry (CRC) as "electron carrier" is proposed to facilitate the electron‐transfer by capturing/providing electrons for the redox of V2O5. The increased oxygen vacancies in V2O5 provoked in situ by CRC offers numerous Zn2+ storage sites and ion‐diffusion paths and reduces the electrostatic interactions between vanadium‐based cathode and intercalated Zn2+, which enhance Zn2+ storage capability and structural stability. The feasibility of this strategy is fully verified by some CRCs. Noticeably, VZB with [Fe(CN)6]3−/[Fe(CN)6]4− as CRC displays conspicuous specific capacity (433.3 mAh g−1), ≈100% coulombic efficiency and superb cyclability (≈3500 cycles without capacity attenuation). Also, the mechanism and selection criteria of CRC are specifically unraveled in this work, which provides insightful perspectives for the development of high‐efficiency energy‐storage devices. [ABSTRACT FROM AUTHOR]

The widespread application of nickel/cobalt-based materials for aqueous alkaline Zn batteries is hindered by the low actual discharge capacity and inferior cycling durability arising from the limited conductivity and electrochemical reaction kinetics. Herein, an effective approach is demonstrated to achieve high-efficiency and flexible cathode of alkaline Ni//Zn batteries by doping sulfur hydrothermally into NiCo 2 O 4 (S–NCO). Compared to bare NiCo 2 O 4 , the S–NCO sample exhibits higher electric conductivity and faster kinetics. Consequently, the alkaline S–NCO//Zn battery presents a higher areal capacity (0.721 mAh cm−2 at the current density of 1 mA cm−2), long-term lifespan without capacity attenuation after 4000 cycles and satisfactory coulombic efficiency of ∼100%. Moreover, an excellent flexibility of S–NCO has been proved by the stable electrochemical performance in the charge-discharge measurements under various bending conditions. [Display omitted] • S-doping endows S–NCO with increased electrical conductivity and active sites. • S–NCO//Zn yields an enhanced capacity of 0.721 mAh cm−2 and cycling durability. • An advanced flexible Ni//Zn battery constructed by S–NCO cathode is achieved. [ABSTRACT FROM AUTHOR]

With the merits of low cost, environmental friendliness and rich resources, manganese dioxide is considered to be a promising cathode material for aqueous zinc-ion batteries (AZIBs). However, its low ion diffusion and structural instability greatly limit its practical application. Hence, we developed an ion pre-intercalation strategy based on a simple water bath method to grow in situ δ-MnO2 nanosheets on flexible carbon cloth substrate (MnO2), while pre-intercalated Na+ in the interlayer of δ-MnO2 nanosheets (Na-MnO2), which effectively enlarges the layer spacing and enhances the conductivity of Na-MnO2. The prepared Na-MnO2//Zn battery obtained a fairly high capacity of 251 mAh g−1 at a current density of 2 A g−1, a satisfactory cycle life (62.5% of its initial capacity after 500 cycles) and favorable rate capability (96 mAh g−1 at 8 A g−1). Furthermore, this study revealed that the pre-intercalation engineering of alkaline cations is an effective method to boost the properties of δ-MnO2 zinc storage and provides new insights into the construction of high energy density flexible electrodes. [ABSTRACT FROM AUTHOR]

Transition metal organic framework materials and their selenides are considered to be one of the most promising cathode materials for nickel-zinc (denoted as Ni-Zn) batteries due to their low cost, environmental friendliness, and controllable microstructure. Yet, their low capacity and poor cycling performance severely restricts their further development. Herein, we developed a simple one-pot hydrothermal process to directly synthesize NiSe2 (denotes as NiSe2-X based on the molar amount of SeO2 added) stacked layered sheets. Benefiting from the peculiar architectures, the fabricated NiSe2−1//Zn battery based on NiSe2 and the Zn plate exhibits a high specific capacity of 231.6 mAh g−1 at 1 A g−1, and excellent rate performance (162.8 mAh g−1 at 10 A g−1). In addition, the NiSe2//Zn battery also presents a satisfactory cycle life at the high current density of 8 A g−1 (almost no decay compared to the initial specific capacity after 1000 cycles). Additionally, the battery device also exhibits a satisfactory energy density of 343.2 Wh kg−1 and a peak power density of 11.7 kW kg−1. This work provides a simple attempt to design a high-performance layered cathode material for aqueous Ni-Zn batteries. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) electrodes hold great potential for supercapacitors (SCs) due to their unique architectures and prominent electrochemical properties. Herein, a kind of 3D FeOOH/reduced graphene oxide/Ni foam (FeOOH/rGO/NF) electrode with remarkable capacitive performance has been developed as a new anode for asymmetric supercapacitors (ASCs). Benefiting from the improved conductivity and increased surface area, the as-prepared 3D FeOOH/rGO/NF electrode exhibits a high areal capacitance of 406.5 mF cm −2 at 10 mV s −1 . Moreover, when using the as-prepared 3D FeOOH/rGO/NF electrode as anode, a high-performance ASC device with a maximum volumetric energy density of 0.48 mWh cm −3 and excellent cycling stability is achieved. [ABSTRACT FROM AUTHOR]

Carbon‐based cathodes for aqueous zinc ion hybrid supercapacitors (ZHSCs) typically undergo low Zn ion storage capability due to their electric double layer capacitance (EDLC) energy storage mechanism that is restricted by specific surface area and thickness of electric double layer (EDL). Here, we report a universal surface charge modulation strategy to effectively enhance the capacitance of carbon materials by decreasing the thickness of EDL. Amino groups with lone pair electrons were chosen to increase the surface charge density and enhanced the interaction between carbon electrode and Zn ions, thus effectively compacting the EDL. Consequently, amino functionalized porous carbon based ZHSCs can deliver an ultrahigh capacity of 255.2 mAh g−1 along with excellent cycling stability (95.5 % capacity retention after 50 000 cycles) in 1 M ZnCl2 electrolyte. This study demonstrates the feasibility of EDL modified carbon as Zn2+ storage cathode and great prospect for constructing high performance ZHSCs. [ABSTRACT FROM AUTHOR]

Carbon‐based cathodes for aqueous zinc ion hybrid supercapacitors (ZHSCs) typically undergo low Zn ion storage capability due to their electric double layer capacitance (EDLC) energy storage mechanism that is restricted by specific surface area and thickness of electric double layer (EDL). Here, we report a universal surface charge modulation strategy to effectively enhance the capacitance of carbon materials by decreasing the thickness of EDL. Amino groups with lone pair electrons were chosen to increase the surface charge density and enhanced the interaction between carbon electrode and Zn ions, thus effectively compacting the EDL. Consequently, amino functionalized porous carbon based ZHSCs can deliver an ultrahigh capacity of 255.2 mAh g−1 along with excellent cycling stability (95.5 % capacity retention after 50 000 cycles) in 1 M ZnCl2 electrolyte. This study demonstrates the feasibility of EDL modified carbon as Zn2+ storage cathode and great prospect for constructing high performance ZHSCs. [ABSTRACT FROM AUTHOR]

The hydrogen evolution and dendrite issues are the notorious culprits of the limited lifespan and Coulombic efficiency (CE) of Zn anodes, particularly at harsh test conditions. Herein, considering the Lewis acidic feature of Zn2+, abundant unshared pair electrons of zincophilic Lewis bases are proposed as decent electrolyte additives to stabilize Zn anodes at "Three High" conditions (high depth of discharge, high areal capacity and high current). The unshared pair electrons can remove H2O from Zn2+ solvated sheaths and confine the activity of H2O by breaking its hydrogen bonding network. The combination of these factors effectively restricts H2O‐involved side reactions and enables dendrite‐free Zn deposition, even at harsh conditions. The effectiveness of this strategy is fully proved by a series of Lewis base molecules. Noticeably, the Zn||Zn cell with an area of 20 cm2, using DMF‐containing electrolyte can be stably cycled over 1000 h at 60 % DOD, with a 100 % CE. [ABSTRACT FROM AUTHOR]

The hydrogen evolution and dendrite issues are the notorious culprits of the limited lifespan and Coulombic efficiency (CE) of Zn anodes, particularly at harsh test conditions. Herein, considering the Lewis acidic feature of Zn2+, abundant unshared pair electrons of zincophilic Lewis bases are proposed as decent electrolyte additives to stabilize Zn anodes at "Three High" conditions (high depth of discharge, high areal capacity and high current). The unshared pair electrons can remove H2O from Zn2+ solvated sheaths and confine the activity of H2O by breaking its hydrogen bonding network. The combination of these factors effectively restricts H2O‐involved side reactions and enables dendrite‐free Zn deposition, even at harsh conditions. The effectiveness of this strategy is fully proved by a series of Lewis base molecules. Noticeably, the Zn||Zn cell with an area of 20 cm2, using DMF‐containing electrolyte can be stably cycled over 1000 h at 60 % DOD, with a 100 % CE. [ABSTRACT FROM AUTHOR]

Fluorescent quantitative PCR (qPCR) and digital PCR (dPCR) are two mainstream nucleic acid quantification technologies. However, commercial dPCR and qPCR instruments have a low integration, a high price, and a large footprint. To solve these shortcomings, we introduce a compound PCR system with both qPCR and dPCR functions. All the hardware used in this compound PCR system is commercially available and low-cost, and free software was used to realize the absolute quantification of nucleic acids. The compound PCR provides two working modes. In the qPCR mode, thermal cycling is realized by controlling the reciprocating motion of the x axis. The heating rate is 1.25 °C s−1 and the cooling rate is 1.75 °C s−1. We performed amplification experiments of the PGEM-3zf (+)1 gene. The performance level was similar to commercial qPCR instruments. In the dPCR mode, the heating rate is 0.5 °C s−1 and the cooling rate is 0.6 °C s−1. We performed the UPE-Q gene amplification and used the sequential actions of the two-dimensional mechanical sliders to scan the reaction products and used the method of regional statistics and back-inference threshold to get test results. The result we got was 1208 copies per μL−1, which was similar to expectations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The 3d-electron configuration of Ni center in Ni 3 S 2 is optimized by an oxidation method. • The underlying working mechanism of this local spin-state tuning strategy is clarified. • The assembled nickel-zinc battery can afford a high capacity of 0.99 mAh cm−2. Nickel sulfide (Ni 3 S 2) has shown great promise as advanced cathode in alkaline nickel-zinc batteries (ANZBs) for its good electrochemical reversibility and electronic conductivity. However, due to the unfavorable OH− adsorption capability and low intrinsic activity of Ni sites originated from the unsuitable d-electron spin state, the overall performances of Ni 3 S 2 are yet unsatisfactory for practical ANZBs. Herein, we demonstrate the engineering of local spit state of Ni sites via a facile electrochemical activation in Ni 3 S 2 to significantly boost its comprehensive energy storage capability. After electrochemical treatment, the spit state of fractional Ni2+ (e g 4 t 2 g 4) sites of Ni 3 S 2 is successfully transformed into high-valence Ni3+ (e g 4 t 2 g 3), which considerably enhances the OH− adsorption capability and redox reactivity. The optimal Ni 3 S 2 electrode exhibits a high capacity of 1.11 mAh cm−2 at 1 mA cm−2 and no capacity decay after 3000 cycles, which are far greater than the pristine Ni 3 S 2 (0.39 mAh cm−2) electrode and also comparable to the best ever-reported alkaline cathodes. Furthermore, the assembled full ANZB can afford a peak energy density of 1.59 mWh cm−2 and power density of 33.92 mW cm−2. This work affords valuable insights into local electronic structure modulation of electrode materials for aqueous energy storage devices. [ABSTRACT FROM AUTHOR]

• A facile organic–inorganic hybrid method was proposed to fabricate the bimetallic phosphide of MoP-RuP x /NPC. • The bimetallic phosphide catalyst with MoP-RuPx was encapsulated into porous N, P co-doped carbon nanosphere. • The improved HER activity of MoP-RuP x /NPC comes from porous nanostructure, abundant defects and the synergistic effect of bimetallic phosphide. Hydrogen evolution reaction (HER) serves as a crucial half reaction in electrolytic water splitting. Pt is deemed to the most active HER electrocatalyst, but the scarcity and high cost of Pt limit its massive application. Developing efficient, low-cost and well-structured HER catalysts is quite vital for advancing the development of water electrolysis technology. Herein, we present a facile organic–inorganic hybrid method to achieve a novel bimetallic phosphide of MoP-RuP x /NPC catalyst, showing superior electrocatalytic activity with an overpotential of 24 and 94 mV at 10 mA cm−2 in alkaline and acid media, respectively. Moreover, MoP-RuP x /NPC also exhibits an outstanding electrochemical stability with a negligible degradation in HER activity after long-term stability measurements. The eminent electrocatalytic performance of MoP-RuP x /NPC catalyst should be ascribed to the high surface specific area, multiple heterogeneous interfaces, strong electronic synergistic effect between MoP and RuP x , and abundant defects. The organic–inorganic hybrid strategy implemented in this work can be used for synthesizing other bimetallic phosphide catalysts. [ABSTRACT FROM AUTHOR]

• Pitch derived porous carbon was synthesized via a molten salt method. • The porous carbon shows high surface area and abundant mesopores. • A high energy density of 36.5 W h kg−1 at 376.6 W kg−1 was achieved. Zn ion hybrid supercapacitors (ZHSCs) are one of the most promising energy storage devices due to its combination of supercapacitor and battery type electrodes. However, the energy density of ZHSCs are still unsatisfying. In this work, we develop porous carbon via molten salt method as high performance ZHSCs cathode. The as-obtained porous carbon shows high specific area as well as abundant mesopores. Consequently, the as-fabricated ZHSCs exhibit a high energy density of 36.5 W h kg−1 obtaining at the power density of 376.6 W kg−1 as well as good cycling stability (85.4 % capacitance retention after 10000 cycles). [ABSTRACT FROM AUTHOR]

• A high-performance uniform MoO 3 nanoparticles with low-valence-state Mo are readily synthesized. • The low-valent-state molybdenum and nanosizing enhances the active sites, electronic conductivity and ion diffusion. • The as-prepared MoO 3-x electrode exhibits a high capacity and excellent stability. Molybdenum trioxide (MoO 3) has become the preferred choice of cathode materials for aqueous zinc ion batteries (AZIBs) because of their multivalency, high theoretical capacity, and unique layered structure. However, MoO 3 suffers from low conductivity and poor cycling stability, which severely limits its practical application for commercialization. Here, we develop a morphological engineering couple valence modulation to remarkably enhance the Zn2+ storage capability of commercial MoO 3 powder. Uniform MoO 3 with low-valence-state Mo (denoted as MoO 3− x) nanoparticles are readily manufactured through a simple solvothermal method with ethylene glycol as a reductant. Taking the merits of the increased electrical conductivity, Zn2+ diffusion rate and active sites, the Zn//MoO 3− x battery achieves a boosted capacity of 144 mAh g−1 at 2 A g−1, substantially superior to the Zn//MoO 3 one (only 17 mAh g−1). In addition, the Zn//MoO 3− x battery exhibits an excellent energy density of 146 Wh kg−1 and good cycle stability with a capacity loss of only 0.07% per cycle over 500 cycles. This work provides an attractive approach to enhance the electrochemical properties of molybdenum-based materials and may open new idea to design advanced cathode material for AZIBs. This work reports a morphological engineering couple valence modulation to remarkably enhance the Zn2+ storage capability of commercial MoO 3 powder. [Display omitted] [ABSTRACT FROM AUTHOR]

• The Ni/C nanosheets provide high conductivity and high surface area for NiMoO 4 nanowires. • The MoO 4 2− additive effectively suppress the structural collapse and dissolution of the NiMoO 4. • The NiMoO 4 -NC electrode yields a high capacity of 221.0 mAh g−1 and extraordinary durability. • An advanced aqueous Ni//Zn battery constructed by NiMoO 4 -NC is achieved. Nickel-based oxides for aqueous rechargeable nickel-zinc (denoted as Ni//Zn) batteries typically suffer from the low capacity and inferior stability due to their slow electron/ion transportation rate and poor electrochemical reversibility. Here, we rationally design a free-standing Ni/C nanosheets (NC) from Ni metal-organic framework as conductive scaffold for NiMoO 4 nanowires (NiMoO 4 -NC), achieving exceptionally high capacity and rate capability. Furthermore, with the use of a new MoO 4 2−-based electrolyte, a stable aqueous Ni//Zn battery with impressive electrochemical performance is also demonstrated based on this NiMoO 4 -NC cathode. Experimental results reveal that the NC skeleton can dramatically improve the conductivity and ion diffusion rate of the NiMoO 4 nanowires, while the addition of MoO 4 2− into electrolyte can effectively suppress the dissolution and structural destruction of NiMoO 4 nanowires. As a consequence, a remarkable capacity (229.2 mAh g−1 at 3.4 A g−1) and excellent durability (85.9% capacity retention after 3000 cycles) are delivered by this Ni//Zn battery, outperforming most reported Ni//Zn batteries. Also, this Ni//Zn battery displays an admirable energy density of 407.8 Wh kg−1, together with a remarkable power density of 18.1 kW kg−1, which is of great significance for future electronic application. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnCo 2 O 4 nanoparticles with Fe surface doped is achieved by quenching treatment. • Quenching endows the ZnCo 2 O 4 electrocatalyst with an active Fe amorphous layer, a higher ratio of Co3+ states and more abundance oxygen vacancies. • The ZnCo2O4-0.01Fe electrocatalyst presents an enhanced OER activities. • This work paves an new route for the surface regulation of metal oxides and its application in the field of energy storage and conversion. Exploring cost-effective and high-performance electrocatalysts for oxygen evolution reaction (OER) is quite significant for utilizing renewable energies by converting them to green hydrogen energy. ZnCo 2 O 4 spinel oxide has drawn a wide attention in water electrolysis field owing to its earth abundance, low cost and eminent electrocatalytic activity. However, it still has a great room to boost its OER catalytic activity due to the low electrical conductivity and restricted active sites of ZnCo 2 O 4 catalyst. Herein, a facile, easy-scalable and environmental-friendly quenching method is exhibited to achieve surface Fe doped and oxygen vacancy generated ZnCo 2 O 4 by instantaneous cooling in Fe(NO 3) 3 solution. As a result, the quenched ZnCo 2 O 4 catalyst shows a vastly improved OER activity in alkaline electrolyte, only requiring an overpotential of 332 mV to reach 10 mA cm−2, which is much lower than that of un-quenched ZnCo 2 O 4 (405 mV). Our results manifest that quenching treatment can endow an active Fe amorphous layer, a higher ratio of Co3+ states and more abundance oxygen vacancies for ZnCo 2 O 4 spinel oxide, thus possessing a higher OER activity. Our work offers an effective path for the regulation of metal oxides and its application in energy catalysis field. [ABSTRACT FROM AUTHOR]

Manganese dioxide (MnO 2) is a promising cathode candidate for advanced rechargeable Zn-ion batteries (ZIBs) owing to its low cost, high theoretical capacity and high output voltage. However, the poor stability and low practical capacity has greatly hampered its commercialization. Herein, we demonstrate a crystal form modulation strategy to enhance the capacity and cycling durability of commercial γ-MnO 2 as robust ZIBs cathode material. By introducing new β-MnO 2 crystal form with compact (1 × 1) tunnel structure after simple calcination, the γ- and β- co-existed MnO 2 (denoted as m -MO) shows enhanced electrical conductivity and structural stability. Consequently, the m -MO cathode exhibits an excellent capacity of 273.6 mAh g–1 at 0.25 A g–1 with good cycle stability, much higher than the pristine γ-MnO 2 cathode (156.7 mAh g–1). Furthermore, an aqueous ZIBs based on m -MO cathode delivers a large peak energy density of 349.1 W h kg–1 at 0.322 kW kg–1 and power density of 4.77 kW kg–1 at 123.01 W h kg–1. This work presents an effective crystal form modulation strategy to construct high-performance ZIBs cathodes based on commercial MnO 2 , which is highly potential for further commercial applications. [Display omitted] • A new kind of γ- and β- co-existed MnO 2 (m -MO) is developed from commercial γ-MnO 2 via crystal form modulation strategy. • The introduction of β-MnO 2 enables m -MO electrode with enhanced capacity and reaction kinetics. • An aqueous rechargeable Zn// m -MO battery with high capacity (273.6 mAh g–1 at 0.25 A g–1) is constructed. [ABSTRACT FROM AUTHOR]

Carbon nanomaterials with remarkable capacitance are highly notable. Although electronic double‐layer capacitors exhibit high power density, their low energy density blocks the practical utility of these carbon materials. Herein, a type of porous‐carbon nanoarchitecture with significant capacitive performance is successfully synthesized using a ZnO template and KOH activation. Benefiting from its excellent conductivity, ultrahigh surface area, and porous architecture, the as‐prepared porous carbon delivers a high capacitance of 245.4 mF cm−2 at a current density of 2 mA cm−2 with impressive rate performance. Moreover, it shows superior cycling durability with more than 99% capacitance retention after 10 000 cycles. A cost‐effective, eco‐friendly, and promising strategy is proposed for the large‐scale preparation of porous‐carbon nanomaterial electrodes. [ABSTRACT FROM AUTHOR]