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The slow kinetics of battery-type anode materials for lithium-ion capacitors (LICs) hinder their matching with capacitive-type cathodes. Designing anode materials with greater capacity and improved rate performance is a key to solving this challenge. Here, we fabricated one-dimensional N, S co-doped carbon encapsulated Fe7S8 nanorods to realize fast lithium storage kinetics and stable cycling performance. The matched Fe7S8@C//AC LICs achieved an extraordinary energy density of 101 Wh kg-1 and a power density of 3927 W kg-1. [ABSTRACT FROM AUTHOR]

In order to cope with the global energy and environmental constraints, researchers are committed to the development of efficient and clean energy storage and conversion systems. Perovskite fluoride (ABF 3), as a novel kind of electrode material, has shown excellent results in recent years in the fields of nonaqueous Li/Na/K-ion storage, aqueous supercapacitors, aqueous batteries, aqueous supercabatteries, electrocatalysis and other related areas, showing promising potential in electrochemical energy storage and conversion. This paper mainly discusses the structure of perovskite fluoride to improve its electrochemical properties by means of elemental doping, morphology control, composite construction and defects modulation, etc., and it also focuses on the electrochemical reaction mechanisms in nonaqueous/aqueous charge storage or catalytic applications, and lastly makes some development suggestions based on the current research status of perovskite fluoride. [Display omitted] • Unfolding structure of ABF 3 with doping, vacancy, morphology and composite. • Showing performance of ABF 3 in electrochemical energy storage and conversion. • Unveiling mechanisms of ABF 3 in charge storage and electrocatalysis. • Proposing suggestions for ABF 3 to be better development in electrochemistry. [ABSTRACT FROM AUTHOR]

Rational synthesis of advanced anode materials is vital in developing high-performance sodium ion batteries. In this work, we report a facile hydrothermal strategy for construction of carbon fibre cloth (CFC) supported MoS2 nanosheet arrays. Interconnected NoS2 nanosheets of 5–10 nm are uniformly grown on the surface of CFC forming arrays structure. Good adhesion and high porosity are obtained in the CFC/MoS2 arrays. When evaluated as anodes of sodium ion batteries, the CFC/NoS2 arrays deliver a high specific capacity of 413 mAh g−1 at a current density of 0·5 A g−1, and 176 mAh g−1 at a current density of 3 A g−1. Additionally, good rate performance and cycling life are proven for the CFC/MoS2 arrays. The good performance is ascribed to the CFC network and arrays architecture. Our synthetic method can be used for fabrication of other advanced metal sulfides anodes for sodium ion batteries. Carbon fibre cloth (CFC) supported MoS2 arrays electrodes are synthesized via a hydrothermal method and exhibit a noticeable electrochemical performance as anode of sodium ion batteries. [ABSTRACT FROM AUTHOR]

Monophasic nanoceramics of calcium doped barium zirconate (BCZ) Ba 1-x Ca x ZrO 3 (x = 0.0, 0.05, 0.10, 0.15 and 0.20) have been manufactured via easy and cost effective metal organic precursor route at 1000 °C. The structural elucidations of the BCZ nanoparticles were confirmed by different analytical techniques i.e. SEM, TEM, XRD etc. Moreover, the elemental composition and detailed surface area were estimated through EDS/EDX and BET analysis. TEM particle sizes of Ba 1-x Ca x ZrO 3 (x = 0.0, 0.05, 0.10, 0.15 and 0.20) were found in the range of 75–42 nm. Mixed (spherical, hexagonal and cubic) morphology and shapes of the nanoceramics were established by SEM and TEM studies. The incorporation of calcium to BaZrO 3 host lattice confirmed by EDS/EDX studies. Very high specific surface area was achieved (233–271 m2 g−1) for Ba 1-x Ca x ZrO 3 (x = 0.0, 0.05, 0.10, 0.15 and 0.20) nanoceramics which is corroborated well with TEM particle size and pore (BJH and DA) size studies. Excellent dielectric properties of BCZ were found at room temperature in the frequency range of 20 kHz to 1 MHz. As the concentration of Ca2+ ion increased the values of dielectric constant were found to increase (48.1–284.7). High surface area and excellent porosity with high dielectric constant of BCZ could make it as an ideal material for energy devices. [ABSTRACT FROM AUTHOR]

Highlights • The NPCSs are successfully prepared by a facile hydrothermal strategy under the assistance of triblock copolymer F108. • The particle size can be tuned from 160 to 2000 nm by adjusting synthesis conditions. • The NPCSs present a high specific capacitance of 365 F g−1 at 0.5 A g−1 and good rate capability. Abstract Porous carbon spheres ranging in size from nanometer to micrometer have been attracting worldwide attention owing to their excellent performance and wide application. In this paper, nitrogen-doped porous carbon spheres (NPCSs) are successfully prepared by a facile hydrothermal strategy under the assistance of triblock copolymer F108 as soft template. The effect of the ethanol/water volume ratios, concentration of F108 and ammonia, and the alkyl chain of alcohol on the morphologies and particle size of the resulted NPCSs are investigated systematically. Results show that the particle size can be tuned from 160 to 2000 nm by adjusting the synthesis parameters. The obtained NPCSs exhibit a large specific surface area (1481 m2 g−1) and suitable nitrogen-doped concentration (2.4 at%). As electrode material for supercapacitors, the NPCSs present a high specific capacitance of 365 F g−1 at 0.5 A g−1 and outstanding cycling stability with 93.9% retention after 10 000 cycles. [ABSTRACT FROM AUTHOR]

High performance of lithium ion batteries (LIBs) largely relies on developing advanced cathode materials. In this work, we report integrated electrodes of graphene foam (GF) supported FeS2 with a novel atomic layer deposition-assisted sulfurisation method. Interestingly, cross-linked FeS2 nanoparticles of 20-40 nm are intimately coated on the preformed GF skeleton forming integrated composite electrodes. The GF/FeS2 electrodes are thoroughly characterised as the cathode of LIBs and proven with high specific capacities (625 mAh g-1 at 0.25 C and 417 mAh g-1 at 2 C), good rate capability and cycling life with a capacity retention of 79% at 0.1 C after 100 cycle. The GF supported binder-free structure is responsible for electrochemical enhancement with fast ions/electrons transportation and good contact between active FeS2 and electrolyte. Our results provide a new high-performance integrated electrode for advanced LIBs. [ABSTRACT FROM AUTHOR]

Looking towards the economical and efficient carbon dioxide (CO 2) utilization, metal-CO 2 batteries uphold a great potential to enhance the efficiency of CO 2 conversion to fuels. Pertaining to this, we have fabricated B, N-containing carbon with tubular morphology (C-BN@600) derived from ionic liquid (IL) and metal-organic framework (MOF) composite as cathode catalyst with Zn foil anode for aqueous rechargeable Zn-CO 2 battery. The C-BN@600 catalyst demonstrate a remarkable activity towards electrochemical CO 2 reduction to methanol with a Faradaic efficiency of 74% and a Yield rate of 2665 μg h−1 mg−1 cat.. The assembled battery consumes CO 2 continuously and electrochemically convert it to methanol during discharge and simultaneously produces electrical energy with a remarkable energy density of 330 Wh kg−1 and a power density of 5.42 mW cm−2 which is stable for more than 12 days (>300 h, 800 cycles) at 1 mA cm−2, providing a platform to serve a dual purpose of CO 2 reduction and energy storage. [Display omitted] • B and N-containing carbon (C-BN@600) was studied for the formation of a value-added product by e-CO 2 R. • CH 3 OH was obtained with a F.E. of 74% at − 0.45 V vs. RHE. • Zn-CO 2 battery exhibited and a high maximum power density of 5.4 mW cm−2. • It showed an excellent cycling durability of more than 300 h (800 cycles) at 1 mA cm−2. • The assembled battery showed remarkable energy density of 343 Wh kg−1 and energy efficiency of 57.5% @ 1 mA cm−2. [ABSTRACT FROM AUTHOR]

Nitrogen-doped porous carbon is synthesised from mineral-rich egg yolks. Pores are produced via successive chemical etching. As anode for sodium ion batteries, the as-prepared carbon showed an initial reversible capacity of 208 mAh g−1 and a high capacity retention of 86% after 200 cycles with good rate capability. [ABSTRACT FROM AUTHOR]

Tailored mesoporous carbon nanostructures (TMCNs) featuring distinctive and tunable morphologies have gained tremendous interest over the past decades. These materials, being ambulant, have broadened the application spectrum. This review aims to provide an authoritative reference regarding the synthesis pathways, potential applications, key challenges, opportunities and future research directions. Regulating the reaction parameters, such as carbonization temperature, precursors types and concentrations, and molecular weight of structural directing agents, was crucial in this context. This review critically evaluates various techniques used to prepare TMCNs such as (i) hard templating, (ii) soft templating, (iii) modified Stöber method, (iv) space confined assembly, and (v) spray pyrolysis with an emphasis on underlying mechanisms and the impact of synthesis methods on the properties of the final product. Considering the importance of TMCN textural properties in the application spectrum, particular focus has been given to their precise tuning to obtain delicate architectural designs. Then, the applications of TMCNs with pre-defined morphologies are discussed in energy storage and conversion, catalysis, adsorption, and biomedicine. Finally, a summary of key aspects and challenges has been provided to put them into a perspective. This review presents the important research needs to foster the controlled synthesis and applications of mesoporous carbon. [Display omitted] • Tailored mesoporous carbon nanostructures (TMCNs) yield desired properties for an innovative application. • Role of synthesis methods in dictating the properties and efficiency of TMCNs is critically evaluated. • Extended applications spectrum of TMCNs in energy, environment and biomedicine is highlighted. • Future research direction and associated challenges of TMCNs are provided. [ABSTRACT FROM AUTHOR]

The search of low cost, highly competent electrode material is the hot research area for various next-gen applications. Herein, cost effective nitrogen doped carbon quantum dots (N-CQDs) anchored in cobalt oxide (Co 3 O 4) nanocomposite was fabricated through a simple hydrothermal method. The fabricated N-CQDs/Co 3 O 4 nanocomposite showed high specific surface area (BET) of ~880 m2 g−1 with BJH pore size and volume of ~21 nm, 0.81945 cm3 g−1 respectively. The electrochemical performance through cyclic voltammetry (CV) in 3-electrode systems exhibited an improved specific capacitance of 1782 F g−1 at 5 mV s−1 in 6 M KOH electrolyte. Additionally, galvanostatic charge–discharge (GCD) analysis showed an improved capacitive performance with a specific capacitance of 1867 F g−1 at 1 A g−1 current density. The energy density was calculated 36.9 Wh kg−1 at the power density of 480 W kg−1. The capacitance retention graph demonstrates 96% stability through 500 GCD cycles. [ABSTRACT FROM AUTHOR]

• A novel nanoforests-like Ni 3 Se 2 consisting of nanosheets grown on nickel foam were successfully prepared. • The nanoforests-like Ni 3 Se 2 as free-standing electrode exhibited high specific capacitance of 600 μAh cm−2 at 3 mA cm−2. • The fabricated hybrid supercapacitor achieved outstanding cycling stability of 94.4% capacity retention over 6000 cycles at 20 mA cm−2. A unique electrode architecture consisting of Ni 3 Se 2 nanosheet-on-Ni 3 Se 2 -nanoforests grown on nickel foam was obtained by a simple one-step solvothermal method, which subsequently used as a free-standing electrode for supercapacitor. The Ni 3 Se 2 exhibited a high capacity of up to 600 μAh cm−2 at 3 mA cm−2, excellent rate capability and cycling stability at high cycling rates. Impressively, the optimized hybrid supercapacitor containing Ni 3 Se 2 cathode still released 94.4% of initial capacity for 505 μAh cm−2 after 6000 cycles at 20 mA cm−2. The results suggest that the Ni 3 Se 2 nanoforests developed electrode has great potential for practical applications in hybrid supercapacitors. [ABSTRACT FROM AUTHOR]

• We prepared unique Mo 3 N 2 NBs with ultra-long nanobelts and stable orthorhombic crystal structure. • Compared with other Mo-N compounds, the Mo 3 N 2 NBs both possessed better electrochemical properties. • More excellent conductivity of Mo 3 N 2 NBs was obtained. As a typical supercapacitor electrode material, the reported Mo-N compounds mostly own one part of outstanding electrochemical properties (specific capacitance (C sp), voltage window and cycling stability), and the well integration with three aspects was rare. Here using a novel MoO 3 precursor with ultra-long nanobelts (NBs) and stable orthorhombic crystal structure, we prepared unique Mo 3 N 2 NBs, which inherited the morphology and structure of the precursor greatly. Compared with other Mo-N compounds, the Mo 3 N 2 NBs both possessed the high C sp (220.3 F/g at 0.4 A/g), great cycling stability (98.3% C sp retention after 1500 cycles) and wide voltage window (0.95 V) due to the improved morphology, stable structure and excellent conductivity. [ABSTRACT FROM AUTHOR]

• A fcc Mo 2 N thin film electrode with porous nano-column array had been prepared by magnetron sputtering. • Electrochemical properties of Mo 2 N as lithium ion battery anode are evaluated. • The porous nano-column array micro-structure enable the Mo 2 N thin film electrode having fast charge transfer. A face-centered cubic Mo 2 N film is successfully prepared on Cu foil by reactive DC magnetron sputtering. The thickness of Mo 2 N film is about 1.5 μm with porous and nano-column array. The Mo 2 N film can be directly used as anode electrode for lithium ion batteries (LIBs) without additional conductive agent and binder. Electrochemical tests including cyclic voltammetry (CV), galvanostatic charge-discharge circulation and electrochemical impedance spectroscopy (EIS) show that the Mo 2 N film electrode exhibits high reversible capacity of 127 μAh/cm2 at a high current density of 1000 μA/cm2 and low charge transfer resistance due to the porous nano-column array. [ABSTRACT FROM AUTHOR]