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• BiOF micro/nanostructures with tunable morphologies were prepared. • NTA molecules was used as structure directing reagents. • The amount of NTA and pH value play vital roles in the reaction. • The photocatalytic activities of BiOF were studied by MG solution under UV light. BiOF with tunable morphologies (polygonal disk-shaped columns, polygonal flakes and square flakes) have been prepared via a facile hydrothermal route, in which nitrilotriacetic acid (NTA) was used as a structure directing reagent. It was found that the morphologies and crystalline structures of the as-obtained BiOF were dependent on the NTA dosage and the pH value. Based on the observation of the photocatalytic selectivity of typical polygonal disk-shaped columns of BiOF towards different types of organic dyes, we further investigated the photocatalytic activities of the BiOF with different morphologies by the degradation of malachite green (MG) solution under UV light irradiation. The results showed that disk-shaped columns of BiOF had the best photocatalytic activity, and the degradation rate of MG reached 95.34 % after 20 min of irradiation. The photocatalytic efficiency was much higher than those of other morphological BiOF micro/nanostructures. The results of this study strongly indicate that BiOF has a broad application prospect in the field of photocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ultrafine PtCo nanoparticles anchored on CNFs is fabricated by rapid heating method. • The obtained PtCo/CNFs-HHR displays outstanding ORR/OER catalytic activity. • PtCo/CNFs-HHR based ZAB exhibits a high peak power density and excellent durability. Herein, rapid heating strategy was introduced to synthesize ultrafine PtCo nanoparticles attached to carbon nanofibers (CNFs) by a high heating rate (HHR) up to about 50 °C s−1. This novel tactic is beneficial to the formation and the homogeneous distribution of ultrathin PtCo nanoparticles on CNFs. The acquired PtCo/CNFs-HHR exhibits a half-wave potential of 0.88 V for ORR, along with a low potential difference ΔE of 0.79 V. When used as the cathode catalyst of ZABs, PtCo/CNFs-HHR displays a high open circuit voltage of 1.454 V, large peak power density of 138.6 mW cm−2, and excellent charge–discharge cycle stability over 300 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mesoporous TiO 2 film was chlorinated by HCl solution and first applied in perovskite solar cells. • It is the first time that the properties of the interface layer between TiO 2 and perovskite are regulated by HCl solution. • The efficiency of C-PSCs based on HCl aqueous solution treated m-TiO 2 layer increased by 7.96 %. • The C-PSCs based on chlorinated TiO 2 have an excellent stability on a large square of 1 cm2. Printable HTM-free (HTM = hole-transporting material) mesoporous carbon-based perovskite solar cells (C-PSCs) are one of the most promising technologies. In this study, a high-quality chlorinated mesoscopic TiO 2 (m-TiO 2) film was obtained by hydrochloric acid (HCl) wet chemical process and applied in C-PSCs based on TiO 2 /ZrO 2 /(5-AVA) x (MA) 1-x PbI 3 /C structures. Experimental results show that the PCE of chlorinated m-TiO 2 C-PSCs greatly improved. Based on (5-AVA) x (MA) 1-x PbI 3 , C-PSCs with TiO 2 ETL treated with HCl aqueous solution achieved an average photovoltaic conversion efficiency of 9.36 %, which is an increase of 7.96 % in comparison with the efficiency of the device using unmodified TiO 2 ETL, while the V oc and the J sc were increased by 3.63 % and 2.63 %, respectively. In a 30-day aging test, C-PSCs based on (5-AVA) x (MA) 1-x PbI 3 and TiO 2 -HCl 1 exhibited excellent stability under ambient air conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • WO/CSE nanocomposites demonstrate exceptional photocatalytic hydrogen evolution, surpassing traditional catalysts. • Trace WO inclusion in WO/CSE significantly boosts photocatalytic efficiency, enhancing overall performance. • The S-scheme heterojunction in WO/CSE is confirmed theoretically, marking a breakthrough in sustainable energy research. Facing the global energy crisis, identifying impactful solutions is imperative. This research introduces the cutting-edge nanocomposites, WO 3 /CdS 0.25 Se 0.75 -Diethylenetriamine (Diethylenetriamine is abbreviated as DETA) with configurations of 20 %, 30 %, and 40 % WO 3 (denoted as 20-WO/CSE, WO/CSE, and 40-WO/CSE), highlighted by its innovative S-scheme heterojunction. WO/CSE nanocomposite stands out in the realm of solar energy materials, achieving a superior photocatalytic hydrogen evolution rate of 16.7 mmol g−1h−1. Additionally, it exhibits exceptional corrosion resistance, maintaining performance integrity over four 12-hour testing cycles. The strategic incorporation of WO 3 not only enhances the nanocomposite's photocatalytic efficiency but also underscores its potential in surpassing the capabilities of its individual constituents. Through theoretical calculations, the S-scheme heterojunction's effective charge transfer properties are confirmed, positioning this nanocomposite as a significant leap forward in addressing energy challenges through advanced solar energy materials and nanocomposites. [ABSTRACT FROM AUTHOR]

• For the first time, Co-metal was used for synthesis of carbon nanopearl chains. • A brand-new carbon nanostructure composed of nanospheres and nanofibers. • Growth based on liquid carbon droplets and Rayleigh's instability. Carbon nanopearl chains (CNPCs) consisted of carbon nanospheres and carbon nanofibers were prepared by chemical vapor deposition (CVD) method using benzene as the carbon source and Co particles on Si-substrate as the catalyst. The characterized results confirmed that the carbon nanospheres with a diameter between 80 nm and 300 nm have solid structure and wavy graphite layered surface, while the carbon nanofibers (diameter: 16 nm) showed amorphous structure and excellent flexibility. Therefore, these synthesized CNPCs can be potentially applied as the reinforcing matrix. Moreover, the growth mechanism of CNPCs has also been proposed by investigating the effects of Co catalyst, thiophene promoter and gas-flow during the growth process. [ABSTRACT FROM AUTHOR]

• MnO x /Ti 3 C 2 T x MXene/CNFs (carbon nanofibers) fiber film was prepared facilely. • MnO x provides high specific capacitance and alleviates the restacking of Ti 3 C 2 T x. • The fiber film electrode shows good electrochemical performance and flexibility. The restack of MXene nanosheets greatly affects its electrochemical performance and application, while electrospinning technique can spin two-dimensional MXene nanosheets into one-dimensional nanofibers, which can prevent the self-stacking of MXene nanosheets. Herein, MnO x /Ti 3 C 2 T x MXene/CNFs (carbon nanofibers) composite fiber films with good flexibility were prepared by combining an electrospinning technique and a carbonization treatment, in which the pseudo capacitive material MnO 2 mixed with carbon nanotube (CNT) was introduced into Ti 3 C 2 T x MXene. The synergistic effect of MnO x , Ti 3 C 2 T x MXene and CNFs improves the capacitance and flexibility of the composite fiber film, and the specific capacitance of the MnO x /Ti 3 C 2 T x MXene/CNFs fiber film electrode delivers 211.57 F·g−1 at a scanning rate of 2 mV·s−1. After 3000 cycles at a current density of 5 A·g−1, it can still maintain 95% of the initial capacitance. The results indicate that the MnO x /Ti 3 C 2 T x MXene/CNFs composite fiber films have great potential for flexible supercapacitors. [ABSTRACT FROM AUTHOR]

[Display omitted] • Self-O-doped Alpinia galanga stem-based carbon nanofiber succesfully synthesis. • The hierarchical porous carbon exhibit high specific surface area of 1065.58 m2/g. • The porous carbon was performed in solid-free binder form. • In 2-electrode system, supercapacitor possessed specific capacitance of 226F g−1. In this study, activated carbon with hierarchical pores and a nanofiber structure doped with oxygen was prepared using a pure biomass-based sustainable strategy involving integrated chemical impregnation and pyrolysis. Alpinia galangal stem was chosen as it functions as fast conductive network with abundant electrochemical active sites for high-grade electrode materials. The optimal precursor exhibited self-doping of oxygen ranging from 6.15 to 15.69 % with 1065.58 m2/g, which contributed to the redox reaction of the electrode material. When tested in a 2-electrode system, the porous carbon nanofibers showed a high specific capacitance of 226F g−1 at 1 A g−1 in 1 M H 2 SO 4 electrolyte, producing an energy density of 9.3483 Wh kg−1 with a coulombic efficiency of 89.01 %. The results showed that oxygen-doped hierarchical porous carbon nanofibers produced from Alpinia galangal stem biomass and designed to be solid-free of binders are highly promising as high-quality electrode materials that can improve sustainable supercapacitor performance. [ABSTRACT FROM AUTHOR]

• The NiFe-LDH nanosheets grow on the carbon nanofibers via an in-situ conversion strategy. • The CNF@NiFe-LDH interlayer can effectively restrict the diffusion of polysulfides. • The CNF@NiFe-LDH interlayer cells exhibit good cyclic and rate performances. • High initial discharge capacity of 799 mAh g−1 at 1 C with a low decay ratio of 0.045 % per-cycle over 500 cycles. To solve the shuttle effect of polysulfides and sluggish reaction kinetics in Li-S batteries, a functional interlayer added between the cathode and separator has been proven to be a very effective means. The pleasing interlayer is usually formed by the conductive skeleton and active components that have polysulfide adsorption and catalytic conversion abilities. In this paper, an electrospinning method assisted with in-site growth strategy has been developed to design a hierarchical functional film with NiFe-LDH nanosheets anchored on carbon nanofibers (CNF@NiFe-LDH). Structural characterizations and electrochemical measurements have been taken to indicate that the CNF@NiFe-LDH interlayer can effectively restrict the diffusion of polysulfides and accelerate the redox kinetics. [ABSTRACT FROM AUTHOR]

[Display omitted] • CC/NCNF/NiFe LDH composites are fabricated by CVD, N doping and electrodeposition. • OER activity of the CC/NCNF/NiFe LDH composites outperforms that of the IrO 2. • Synergy between NCNFs and NiFe LDHs contributes to OER activity of the composites. Nitrogen doped carbon nanofibers (NCNFs), which are grown on carbon cloth (CC) and loaded with NiFe layered double hydroxide (LDH) nanosheets, are synthesized by chemical vapor deposition, ammonia annealing and electrodeposition. The obtained three dimensional CC/NCNF/NiFe LDH composites demonstrate an overpotential of 220 mV at current density of 10 mA cm−2 and a small Tafel slope of 30 mV dec−1 for oxygen evolution reaction (OER), both of which are superior to those of the state-of-the-art iridium oxide catalysts. The excellent OER performances of the CC/NCNF/NiFe LDH composites may be attributed to collective contributions of large surface areas of CNFs, nitrogen doping and synergy between NCNFs and NiFe LDHs. [ABSTRACT FROM AUTHOR]

• A facile method was reported by us to sustainably obtain 3D and defective nanocarbon from waste RS residue. • The key role of bacterial played in the formation of RS residue with unque structure and composition was revealed. • The underlying pyrolysis mechanism of RS residue is explored. • The obtained bio-char was demonstrated as a promising candidate for supercapacitor. Defective carbon nanomaterials with three-dimensional (3D) structure are showing great potential for advanced electrochemical storage and conversion devices, but its application is restricted by the synthesis, which is usually involved with complicate and energy-intensive processes. Herein, pyrolysis of rice straw (RS) residue, of which is collected from the bacterial assisted hydrolysis, is proposed by us here, and the obtained bio-char is defective with 3D structure and rich in oxygen-containing functional groups. Compared to the pristine one, specific surface area of the representative RS carbon (RSC2) was increased from 428.8 to 1131.7 m2 g−1. The assembled supercapacitor with RSC2 showed a high specific capacitance of 331F g−1 at a charge–discharge current density of 0.5 A g−1, and a capacity retention of 97.6% was maintained at 5 A g−1 even after 10,000 cycles. [ABSTRACT FROM AUTHOR]

• SnO 2 nanoparticles are encapsulated in nanofibers by electrospinning. • The nanofiber structure facilitates the passage of charges through the channel. • Such nanochannels reduce the effect of large volume changes during the cycle. • SnO 2 @CNFs-0.35 show outstanding cyclic performance and reversible capacity. With the improvement of energy demand, the requirements for energy storage systems are becoming increasingly high, such as high capacity and environmental friendliness. Therefore, it is necessary to develop new electrode materials to meet the requirements. Tin is a low-cost electrode with low working potential and high volume to mass ratio. However, in the first circulation of lithium battery, large volume changes are likely to cause capacity loss. Thus, we designed the use of electrospinning to encapsulate SnO 2 in nanofibers, forming channels that facilitate charge passage and reducing the impact of significant volume changes during cycling. The results show that the capacity of SnO 2 @CNFs-0.35 can still reach 197.6 mA h g−1 after 3000 charge–discharge cycles at 1A g−1 current density, and the capacity retention rate can still reach nearly 99% after 3000 cycles. It shows outstanding cycling stability and high reversible capacity. The simple synthesis method and good electrochemical performance make SnO 2 @CNFs-0.35 an ideal candidate material for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• SiO@C composite materials are constructed with phenolic resin pyrolysis method. • SiO@C has an outer rigid carbon coating that effectively alleviates large volume changes. • High durability of the core–shell structure improves the cycling stability of anode. • SiO@C-20 exhibits a discharge capacity of 603 mAh·g−1 after 100 cycles. Silicon monoxide (SiO) is suggested as anode for LIBs with excellent theoretical capacity. Unfortunately, the low electrical conductivity and volume expansion limit its practical application. The preparation of SiO@C composites can effectively solve these problems. SiO@C composite materials are constructed with phenolic resin pyrolysis method. Experimental data indicate that SiO@C-20 with carbon content of 20 wt% possesses a high discharge capacity and superior initial coulombic efficiency (74.81 %) compared to others. The superior performance can be attributed mainly to carbon ratio with adjusting phenolic resin. [ABSTRACT FROM AUTHOR]

• TiO 2 /carbon nanofibers with in-situ Fe-doping was successfully prepared. • Fe-TiO 2 /carbon nanofibers could deliver a capacity of 140 mAh/g at 30 C. • Fe-TiO 2 /carbon nanofibers could achieve 98% capacity retention after 3000 cycles. TiO 2 is recognized as a promising anode material for sodium-ion batteries (SIBs) due to its low-cost and high structural stability, but it suffers from intrinsically poor electrical conductivity and low electrochemical activity at high rates. Herein, an in-situ Fe-doping strategy is designed to increase sodium-ion storage performance of TiO 2 /carbon nanofibers by a simple electrospinning method. The combination of Fe-doping with one-dimensional carbon structure could enable fast electron and Na+ ion transport of TiO 2. As a result, the Fe-TiO 2 /carbon nanofiber electrode exhibits high specific capacity (283 mAh g−1 at 0.5 C), excellent rate capability (140 mAh g−1 at 30 C) and long cycling stability (98% retention after 3000 cycles), which is obviously superior to pure TiO 2 /carbon nanofiber and other TiO 2 -based anodes reported in the literatures. These results indicates the powerful effect of in-situ Fe-doping for enhancing the Na-storage property of TiO 2. [ABSTRACT FROM AUTHOR]

• Photo-anodes based on TiO 2 nanofibers decorated with carbon dots. • High enhancement of photo-electrochemical properties in the presence of carbon dots. • Application in the field of hydrogen evolution. Wide band-gap semiconductor TiO 2 is an efficient anode material for photo-electrocatalytical (PEC) applications. Its light-sensitivity is limited to the UV but can be extended to the visible by chemical doping or chromophore sensitization. Moreover, its conductivity can be enhanced by coupling with carbon materials, which should limit back electron-hole recombination. In this context, we prepared hetero-nanostructures based on TiO 2 nanofibers supported on Ti sheet and impregnated with carbon dots (CDs), and used them as photo-anodes in photo-electrochemical cells. They showed a higher photocurrent than non-CD-impregnated photo-anodes, underlining the importance of CDs for water-splitting processing. [ABSTRACT FROM AUTHOR]

• Energy storage mechanism is closely related to electrode morphology. • "ESize" can significantly improve more "real" capacitive part than "EArea". • LFS/C-Fiber shows excellent physical and interfacial stability. Powdered and fibrous Li 2 FeSiO 4 /C (LFS/C) composites with similar carbon content were synthesized by traditional solid-state route and electrospinning technique, respectively, for investigating initial aqueous super-capacitive mechanisms. The relationship between the scan rate and response current revealed their storage mechanisms, indicating that the LFS/C-Fiber displays more capacitive contribution to the total energy compared to that of LFS/C-Powder. The improved capacitive contribution is attributed to the morphological characteristics that partially increased the insertion contribution compared to that of the capacitive one. Furthermore, compared to the "Area Effect (E Area)", the "Size Effect (E Size)" significantly increased the "real" capacitive part. Consequently, for the development of a high-rate and quick charge/discharge device, the morphological characteristic of synthesized composites should be considered as an essential factor. [ABSTRACT FROM AUTHOR]

The typical experimental flowchart of Ni 3 (VO 4) 2 nanofibers by electrospinning and schematic illustration of photoelectron-hole pair separation mechanism. • Superfine Ni 3 (VO 4) 2 nanofibers are rational designed by an electrospinning strategy. • The band structure and density of states of Ni 3 (VO 4) 2 are simulated via VASP. • 1D superfine Ni 3 (VO 4) 2 nanofibers possess the excellent photoelectric performance. One-dimensional superfine Ni 3 (VO 4) 2 nanofibers with diameter about 60 ± 5 nm have been successfully synthesized by simple and efficient electrospinning process. The construction and photoelectrochemistry performance of photocatalysts are characterized in detail. The relationships between the structures and photocatalytic activities are also discussed detailedly. Compared with Ni 3 (VO 4) 2 powders, superfine Ni 3 (VO 4) 2 nanofibers possess the excellent photoelectric properties, which could be attributed to the specific dimensional effect and large surface area. Moreover, the energy band structure, density of states and free energy of different crystal planes of Ni 3 (VO 4) 2 nanofibers have been simulated by density functional theory and explained in detail. [ABSTRACT FROM AUTHOR]

• Porous carbon nanofibers were prepared by one-step method with ZnCl 2. • The structures of the porous carbon nanofibers were investigated systematically. • PCF-5 presented excellent MA due to the dielectric loss and multiple reflections. In this research, 1D porous carbon nanofibers (PCFs) were prepared by electrospinning and annealing process. The PCFs with excellent microwave absorption (MA) performance were prepared by a simple one-route method by mixing with different amount of ZnCl 2 in the precursors. During the process of annealing, ZnCl 2 can promote the formation of porous structures and ZnO or Zn complexes by gasifying at high temperature. The porous structures can enhance the multiple reflections and the ZnO or Zn complexes can enhance the dielectric loss. The obtained PCFs were characterized by SEM, TEM, XRD, Raman and XPS. The PCFs with 5 wt% ZnCl 2 exhibit excellent microwave absorption properties with a minimum reflection loss (RL min) of −51 dB at 9.1 GHz and the effective band under −10 dB ranges from 8 to 11 GHz with a width of 3 mm. It is believed that this method would be a facile approach for preparing porous carbon fibers as lightweight microwave absorption materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Direct synthesis of fractal-like carbon nanoparticles derived from candle soot. • Carbon nanoparticles decorated carbon nanofiber hybrid structure as a flexible anode. • The binder-free anode delivered a high initial discharge capacity of 1030 mAh g−1 at 0.05 A g−1. • Good rate capability and high stability at a high current rate. This work demonstrates a unique fractal-like candle soot-derived carbon nanoparticles (CSC) decorated onto nitrogen-doped carbon nanofibers (CSC@N-CNFs) by a one-step electrospinning process as a self-standing flexible anode for lithium-ion battery (LIB). The CSC nanoparticles exhibit a short-range ordered structure with large interlayer spacing for enhanced Li ion storage. In addition, the N-CNFs provide flexibility and stability to prevent volume expansion during electrochemical reactions. The synergistic impact of the hybrid structure provides the flexible anode with a high initial discharge capacity of 1030 mAh/g at 0.1C with an outstanding coulombic efficiency of ∼100% at 30C (5 A/g). The enhanced performance is due to the increased electrical conductivity from N-doping from CNFs, the hard carbon morphology of CSC nanoparticles, the 3D interconnected nanofiber framework, and the binder-free flexible nature. [ABSTRACT FROM AUTHOR]

• Series of Cu x NiCo 2−x O 4 synthesized by Microwave hydrothermal method. • The average grain size is in the range of 30–55 nm. • Highest Specific capacitance, C sp = 250.66 Fg−1 is observed for x = 0.06 sample. • Highest E = 22.22 Whkg−1 and P = 757.80 Wkg−1 were observed for x = 0.06 sample. A series of NiCu x Co 2-x O 4 with x = 0, 0.02, 0.04, 0.06, 0.08 and 0.10 samples were synthesized using microwave hydrothermal method (MH). The structural, microstructural, and spectroscopic characterizations were carried out using X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). All the samples are in Cubic phase with space group Fd3m. The samples x ≥ 0.08 shows some impurity phases. The average grain size for all the samples is in the range of 30–55 nm. The specific capacitance (C sp) 250.66 Fg−1, energy density (E) 22.22 Whkg−1 and power density (P) 757.80 Wkg−1 was observed for x = 0.06 with a mass loading of 7 mgcm−2 and in 2 M aqueous KOH electrolyte solution at a current density of 1 Ag−1. Therefore, the Cu doping with x = 0.06 shows good redox activities and hence can be used in electric batteries and supercapacitors. [ABSTRACT FROM AUTHOR]

• Sn/RGO/CNF are newly designed to broaden the variety of the Sn/C composites. • The introduction of RGO and CNF prevents the agglomeration of nanosized Sn. • Sn/RGO/CNF have displayed a reversible capacity of 643 mAh g−1 after 90 cycles. • The integration of nanosized Sn, RGO and CNF results in synergetic effect. Novel Sn/reduced graphene oxide/carbon nanofibers ternary hybrids have been designed via a facile one-step synthesis process. In the hybrids, Sn nanoparticles, uniformly sandwiched in the layers of reduced graphene oxide, are in good contact with carbon nanofibers. The ternary hybrids have demonstrated superior lithium storage performance to the Sn/reduced graphene oxide and Sn/carbon nanofibers binary hybrids. The reversible capacity of the ternary hybrids is 643 mAh g−1 after 90 cycles. Importantly, electrochemical impedance spectroscopy measurements confirm that the integration of Sn, reduced graphene oxide and carbon nanofibers can reduce the charge transfer resistance effectively. [ABSTRACT FROM AUTHOR]

Highlights • BCNT/CNF composites were synthesized by a single step method. • BCNT/CNF-based supercapacitors exhibit very high specific capacitance. • BCNT/CNF-based supercapacitors deliver an energy density of 63.7 Wh kg−1. Abstract We describe the in situ synthesis of branched carbon nanotubes/carbon nanofibers (BCNT/CNF) nanocomposite by a simple chemical vapor deposition method. Electrochemical characterization indicated that the BCNT/CNF based supercapacitors carried a high value of specific capacitance up to 207 F g−1 at a charge/discharge rate of 1 A g−1, which is much higher than branched carbon nanotubes (BCNT) in H 2 SO 4 electrolyte. The supercapacitor showed a very good cycling stability of 95.6% after 5000 charge/discharge cycles at a very high current density of 20 A g−1, and high energy density of 63.7 Wh kg−1 in EMIBF 4 organic electrolyte. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • FeCoNi ternary alloy embedded mesoporous carbon nanofibers has been fabricated. • FeCoNi-CNF shows excellent electrocatalytic activities for OER. • Zn-air battery with FeCoNi-CNF exhibits high power density and a long-term stability. Abstract FeCoNi alloy embedded mesoporous carbon nanofiber (FeCoNi-CNF) has been prepared via electrospinning and subsequent carbonization. Benefiting from the unique FeCoNi alloy composition and porous 1D carbon structure, FeCoNi-CNF presented an overpotential of 220 mV at 10 mA cm−2 and a Tafel slope of 57 mV dec−1 as an OER catalyst. It also exhibited a low discharge–charge voltage gap (0.88 V, at 20 mA cm−2), higher power density (73 mW cm−2, at 80 mA cm−2) and long-term stability when testing for Zn-air battery. [ABSTRACT FROM AUTHOR]

Highlights • A facile strategy is used to construct 3D freestanding VN-NCNFs current collector. • VN-NCNFs are directly used as current collector without addition of conductive additives or polymer binder. • VN-NCNFs with multichannel structure are beneficial to S species utilization, and volume accommodation. • VN has catalytic effect to enhance the redox kinetics of S species. Abstract In the present study, a facile strategy to construct 3D vanadium nitride (VN)-decorated lotus root-like N-doping carbon nanofibers (VN-NCNFs) as current collector with stable electrochemical performance for Li-S batteries was described. The polar conductive VN with catalytic property provides chemical adsorption to trap lithium polysulfides (LiPSs) and enhances the transformation of LiPSs. The Li-S batteries with as-prepared VN-NCNFs current collector display stable cycling performance with a capacity of 700 mAh g−1 after 500 cycles at 0.2 C. [ABSTRACT FROM AUTHOR]

Highlights • SnS 2 nanoparticles impregnated in carbon nanofibers was prepared by electrospinning. • The CNFs skeleton improves the electronic conductivity and structural stability. • SnS 2 @CNFs anode exhibits excellent electrochemical performance. Abstract To solve the problems of insufficient conductivity and volume expansion of SnS 2 during cycling when applied as anode for sodium-ion batteries (SIBs), we designed flexible and self-standing SnS 2 /carbon nanofibers (SnS 2 /CNFs) film by electrospinning technology and post sulfuration, in which the ultrafine SnS 2 nanoparticles (∼5 nm) are preganated in the carbon nanofibers. The three-dimensional carbon nanofibers serve as flexible scaffold with high electrical conductivity to buffer the aggregation and pulverization of SnS 2 particles. The obtained flexible SnS 2 /CNFs film can be directly used as anode for SIBs without adding binder and carbon additive, and exhibits excellent electrochemical performance. The SnS 2 /CNFs delivers a high capacity of 570.8 mAh g−1 at 0.2 A g−1. Even at a high rate of 5 A g−1 , a high capacity of 247.1 mAh g−1 is still achieved. It also maintains 378.9 mAh g−1 after 100 cycles at 0.5 A g−1. [ABSTRACT FROM AUTHOR]

Highlights • Na 3 V 2 (PO 4 ) 3 /C nanofibers are prepared by electrospinning and heat treatment. • The as-obtained Na 3 V 2 (PO 4 ) 3 /C nanofibers can be used as self-standing cathodes. • The NVP particles were embedded in uniform porous carbon nanofibers to form a flexible 3D network structure. • Even at a rate of 30 C, the discharge capacity was up to 30 mA h g−1. Abstract A facile and simple electrospinning method was adopted to prepare a 3D network of Na 3 V 2 (PO 4 ) 3 /C flexible fiber membrane as self-standing cathodes for sodium ion batteries. The physical and electrochemical performances are investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and electrochemical tests. The Na 3 V 2 (PO 4 ) 3 /C nanorods displayed an excellent sodium storage performance. For example, it showed an initial capacity of 107 mA h g−1 at a current density of 0.1 C and retained almost 100% of the initial capacity at the 100th cycle. Moreover, the discharge capacity was up to 30 mA h g−1 at 30 C, suggesting a high rate capability. [ABSTRACT FROM AUTHOR]

Nitrogen-doped micropores-contained carbon nanofibres (NMCNFs) were prepared by carbonizing ZIF-8 grown in liquid-phase along with electrospinning. When NMCNFs act as sulphur host materials in lithium–sulphur batteries, NMCNFs can retard the shuttle effect and dissolution of polysulfides through the synergic action of effective physical confinement to micropores and nitrogen surface chemical absorption. NMCNFs show a capacity up to 636 mAh g −1 after 500 cycles against Li anode. [ABSTRACT FROM AUTHOR]

Freestanding membrane built from interwoven carbon fibers with encapsulated liquid gallium (Ga) nanodroplets has been demonstrated via the ultrasonic cell disrupting and electrospinning approaches along with a subsequent annealing process. Employing this membrane as a freestanding anode for lithium storage, the severe volume changes of Ga can be effectively accommodated due to the unique encapsulated 3D network structure. As a result, the membrane exhibits superior electrochemical performance, including high reversible capacity (450 mAh g −1 ), enhanced cycling stability (247 mAh g −1 at 0.65 A g −1 over 250 cycles), as well as good rate performance (200 mAh g −1 at 2 A g −1 ). [ABSTRACT FROM AUTHOR]

Composite of two metal oxides, SnO 2 and TiO 2 , is synthesized as 3D nanoflowers in large quantities by electrospinning technique. They show superior energy storage properties and photocatalytic performance than their components or conventional electrospun 1D nanofibers. [ABSTRACT FROM AUTHOR]

A novel mesoporous carbon nanofibers (MCNF) have been successfully prepared as host materials for lithium-sulfur batteries by electrospinning method. The unique mesoporous and fiber structure not only minimizes polysulfides dissolution but also substantially buffers the volume expansion of sulfur during cycling as well as improving conductivity. As a result, the mesoporous carbon nanofibers sulfur (MCNF/S) composites exhibit excellent cycle performance. The MCNF/S composite electrodes deliver a high initial capacity of 1015 mAh g −1 and maintain 721 mAh g −1 after 500 cycles at 1 C. [ABSTRACT FROM AUTHOR]

• The ZnO/Ni 3 ZnC 0.7 /NCNF nanofibers are prepared by a simple and fast method. • The ZnO/Ni 3 ZnC 0.7 /NCNF anodes exhibit outstanding electrochemical performance. • The reaction processes are controlled by both diffusion and capacitance behavior. Transition metal oxides (TMOs) have the advantages of high theoretical capacities, environmental benignity, low cost and abundant supply. However, their applications as anodes for lithium-ion batteries are seriously limited for the intrinsically poor conductivity and inevitable volume variation. To solve such problems, ZnO/Ni 3 ZnC 0.7 /NCNFs composite nanofibers are designed through electrospinning and subsequent thermal treatment. Herein, ZnO/Ni 3 ZnC 0.7 nanoparticles are uniformly distributed in N-doped carbon nanofibers, which can greatly improve the conductivity and stability of active materials. When applied as anode materials, ZnO/Ni 3 ZnC 0.7 /NCNFs prepared at 600 °C shows the optimal electrochemical performance with the reversible specific capacity of 739.3 mA h g−1 after 150 cycles. [ABSTRACT FROM AUTHOR]

As catalytic active sites of nitrogen (N)-doped carbon nanomaterials (CNMs) for oxygen reduction reaction (ORR) are always under debate, synthesis of high purity pyridinic-N dominated CNMs is an effective approach to study the relation between pyridinic-N and active sites, as well as catalytic mechanism for ORR. Herein, the carbon nanofibers (CNFs) etched by hydrofluoric (HF) acid can be used to synthesize pure pyridinic-N, suggesting that the exposed edge-patterned surface facilitates to synthesize pure pyridinic-N. Moreover, it reveals that the carbon atoms adjacent to pyridinic-N could be the catalytic active sites for ORR. [ABSTRACT FROM AUTHOR]

In this study, the SnO 2 -graphene-carbon (SnO 2 -G-C) nanofibers are synthetized via an electrospinning method and employed as potential KIB anodes. The SnO 2 -G-C anodes exhibit a great cycling stability of 202.06 mA h/g over 100 cycles at the current density of 100 mA/g, as well as the high rate capacity of 114.81 mA h/g at 1 A/g. The enhanced electrochemical properties of SnO 2 -G-C comparing to SnO 2 -carbon (SnO 2 -C) counterpart can be ascribed to the dispersive graphene inside the carbon nanofibers, which offers flexible buffer matrix and protects the active materials from destruction. Meanwhile, the graphene facilitates the electrons transportation, leading to the good rate capability. [ABSTRACT FROM AUTHOR]

A novel porous and magnetic Fe/FeN X composite fibers for Cr (VI) ions adsorbent were prepared by electro-blown spinning technology coupled with high temperature nitrided way. The X-ray Diffraction (XRD) and Differential Scanning Calorimetry-Thermo Gravimetric Analyzer (DSC-TGA) revealed metallic iron and FeN X mainly existed in these fibers. Furthermore, the effect of spinning voltage, air pressure and solution concentration on the morphology for the as-spun fibers were investigated. Meanwhile, the effect of calcination temperature on morphology and structure, crystalline property and hysteresis loop also were discussed. The obtained fibers had a uniform morphology and structure, and a high specific surface area (151 m 2  g −1 ) during the calcination temperature of 800 °C. The Fe/FeN X fibers showed effective sorption affinity for Cr (VI) ions, achieving maximum adsorption capacities of 79.21 mg/g at 25 °C. It mainly was ascribed to the existence of metallic iron in the obtained fibers. Meanwhile, the FeN X contents in the fibers were extremely beneficial to the adsorbent recovery. [ABSTRACT FROM AUTHOR]

We report a carbon-sulfur nanostructure by impregnating sulfur into activated N-doped hollow carbon nanofibers (ANHCNFs) with a high Brunauer-Emmett-Teller (BET) specific surface area of 608 m 2 g −1 and a total pore volume of 0.8 cm 3 g −1 . As a cathode, this material with 50 wt% sulfur shows a reversible capacity of 1230 mAh g −1 and maintains ∼920 mAh g −1 after 100 cycles at 0.2 C (1 C = 1675 mA g −1 ). These results show that the ANHCNFs-S could be a superior cathode material for Li-sulfur battery. [ABSTRACT FROM AUTHOR]

Mechanically flexible electrospun carbon nanofiber (ECNF) mats were prepared by electrospinning mixtures containing hydrothermal liquefaction (HTL) derived biochar and polyacrylonitrile (PAN) into precursor nanofiber mats followed by stabilization in air and then carbonization in argon. The resulting ECNF mats well retained the overall morphological structures of their precursors ( i.e. , biochar/PAN composite nanofiber mats), and the carbon nanofibers showed the enlarged specific surface area upon the increase of biochar loading amount in precursor nanofibers. The ECNFs (4/10), which were derived from composite nanofibers with the biochar/PAN weight ratio being 4/10, had the fiber diameters of ∼350 nm and the BET specific surface area of 30.12 m 2 ·g −1 ; and these ECNF mats exhibited the highest gravimetric capacitance of 37.60 F·g −1 at the current density of 500 mA·g −1 . Hence, the prepared ECNF mats could potentially be utilized for energy related ( e.g. , supercapacitor) applications. [ABSTRACT FROM AUTHOR]

A prospect of using metal dusting as an approach to synthesize self-organizing Ni-based catalysts for production of bimodal carbon materials has been discussed. Forced metal dusting of bulk Ni-M alloys driven by decomposition of chlorinated hydrocarbons led to a rapid and full disintegration of alloyed Ni-M precursors with spontaneous formation of active catalytic particles responsible for the growth of carbon filaments. Self-organizing catalysts were shown to be effective for utilization of organochlorine waste, processing of freons and various hydrocarbons into carbon nanomaterials. Secondary disintegration of metal particles resulted in the appearance of bimodal structures. The structural and morphological peculiarities of carbon nanomaterials obtained have been described. [ABSTRACT FROM AUTHOR]

Silicon/graphene/carbon composite nanofibers (Si@RGO@C NFs) with a hierarchical structure are prepared by encapsulating graphene coated Si nanoparticles in the interconnected carbon nanofibers based on an electrospinning technology. For the hierarchical structure, Si nanoparticles are embedded in the graphene and the core-shell structure formed, which is further wrapped by the carbon nanofibers. As lithium ion battery anode, the well-defined Si@RGO@C NFs demonstrates a reversible capacity of 1228 mAh g −1 and a capacity retention of 72% after 100 cycles with a current density of 800 mA g −1 . With the current density gradually increasing to 4000 mA g −1 , the electrode displays a specific capacity of 954 mAh g −1 , exhibiting superior rate capability compared to the Si nanoparticles. These excellent electrochemical properties are attributed to the hierarchical core shell structure and cross linked network for Si@RGO@C NFs. [ABSTRACT FROM AUTHOR]

• The TiO 2 nanoparticles are formed on the pre-oxidized PAN nanofibers in ScCO 2. • Activation heat treatment improves the adsorption and photocatalysis of fibers. • TiO 2 /ACNF has the best degradation effect on methyl orange solution. Polyacrylonitrile (PAN)-based activated carbon nanofibers were used as a photocatalyst carrier and framework due to its large specific area and can adsorb organic pollutants. In this paper, the supercritical carbon dioxide was used to deposit TiO 2 on the surface of pre-oxidized PAN nanofibers, and the fibers were activated by heat treatment to prepare activated carbon nanofibers-TiO 2 (TiO 2 /ACNF). The morphology, structure and specific surface area of the modified nanofibers were analyzed, and the degradation test of methyl orange was carried out. The results showed that TiO 2 nanoparticles can be uniformly loaded on the surface of pre-oxidized PAN nanofibers after supercritical treatment. The specific surface area of the TiO 2 /ACNF after activated heat treatment can reach 422.8 m2/g, having higher adsorption and photocatalytic degradation performance. [ABSTRACT FROM AUTHOR]

• The PANI decorated activated carbon nanofibers (PANI/CNF-A) were prepared. • The symmetric supercapacitor device was fabricated using PANI/CNF-A. • The fabricated device showed a good energy density of 13.3 Wh kg−1. • The device showed a remarkable cyclic stability of nearly 100% after 5,000 cycles. Polyaniline (PANI) decorated salt-activated phenolic resin (PR)/polyacrylonitrile (PAN)-based carbon nanofibers (PANI/CNFs) were fabricated by the consecutive solution electrospinning, salt activation and PANI electrodeposition methods for supercapacitor applications. The electrochemical energy storage properties of the PANI-decorated activated PANI/CNFs (activated PAN: CNF-A, activated PR/PAN28 (weight ratio of PR and PAN is 2:8): CNF28-A) were evaluated by assembling the electrodes into a symmetric supercapacitor (SSC) device. The specific capacitance of the device was ca. 336F g−1 at the current density of 1 A/g. The device possessed an energy density of 13.33 Wh kg−1 at a power density of 200 W kg−1 with a retention life of nearly 100 % after 5,000 cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu 0.95 Co 2.05 O 4 /Metal/NF exhibited relatively excellent performance. • The performance of Cu 0.95 Co 2.05 O 4 /Au/NF is good due to the close lattice spacing. • The metal buffer layer can effectively reduce the transfer resistance. The method of forming Cu or Au buffer layer on nickel foam (NF) by magnetron sputtering technology to enhance the energy storage capacity of following prepared supercapacitor anode material of Cu X Co 3-X O 4 was carried out in this paper, and the feasibility of surface treatment to improve the performance of supercapacitors was discussed. The buffer layer of Cu or Au can attenuate the lattice mismatch between NF and Cu X Co 3-X O 4 , and thus greatly reducing the transfer resistance and improving the electrochemical performance of the electrode material. The effect of Au is more obvious than Cu. The transfer resistance could be decreased effectively from 1.213 Ω to 0.012 Ω after Au sputtered, and the specific capacity increased spontaneously from 442.1C/g to 744.5C/g at a current density of 1A/g. The asymmetric supercapacitor (ASC) based on the modified anode material can achieve an energy density of 51.04Wh/kg when the power density is about 800 W/kg, and 93.9 % capacity retention rate after 4000 cycles. [ABSTRACT FROM AUTHOR]

• Hierarchical conductive network improves the overall electrochemical performance. • Continuous composite carbon nanofiber coated exhibits favorable flexibility. • The fiber structure is well compatible with high active material load and high flexibility. In spite of its wonderful mechanical flexibility and conductivity, the highly oriented and continuous carbon nanofibers (CNFs) fabric has been hindered from widespread use, due to the low energy density. This work proposes a high SiO loading and free-standing N -doped composite nanofiber fabric by hybrid electrospinning, carbonization and gel solution impregnation. The 3D hierarchical conductive network enhances the conductivity of both the electrons and ions, and protects the SiO from structure collapse. The composite gains bending resistance and a high specific capacity of ∼670 mAh·g−1 at 160 mA·g−1 after 95 cycles. The composite conductive gel-coated SiO/CNFs fabric provides an effective strategy for flexible lithium-ion batteries. [ABSTRACT FROM AUTHOR]

• Substrate free Cu-CNFs were synthesized by CVD technique from Cu-tartrate. • Fe 3 O 4 NPs were distributed onto Cu-CNFs uniformly and homogeneously. • The material was characterized using analytical and spectroscopic techniques. • The material exhibited excellent crystal violet adsorption capacity at high solution pH. Herein, we demonstrate a substrate free synthesis route for Cu-carbon nanofibers (Cu-CNFs) from Cu-tartrate. Optimization of the reduction temperature of Cu-tartrate by temperature programmed reduction (TPR) analysis is found to be crucial for the successful growth of Cu-CNFs. Magnetite (Fe 3 O 4) NPs are further incorporated onto Cu-CNFs by wet-impregnation technique. Physico-chemical properties of the materials are evaluated using various analytical and spectroscopic techniques. The material is further tested for its adsorption efficacy towards crystal violet dye. A high adsorption capacity (260 ± 5 mg/g at pH value of 11 measured by Langmuir model) may be attributed to the combined effects of negative surface charge, hydrophilic characteristic, and high surface area of the material. In its dual role, Fe 3 O 4 NPs facilitates the adsorption of CV onto the adsorbent and also separates the adsorbent efficiently from the aqueous mixture using an external magnet. The synthesized material may also be utilized for the adsorptive removal of other cationic dyes from wastewater. [ABSTRACT FROM AUTHOR]

The combination of graphene nanoplatelets and carbon nanofibers were successfully fabricated by utilizing a one-step solution based on the electrospinning technique. A distinctive morphology was observed in which the platelets were suspended between the fibrous structure that significantly improved the specific capacitance of the nanofiber to 86.11 F g −1 , twice the increment from its original structure. Furthermore, all of the graphene nanoplatelets-reinforced samples recorded an optimal performance of over 90% capacitive retention after 1000 continuous charge/discharge cycles, regardless of the GnP concentration. These findings indirectly reflect the potential of CNF as the electrode material in the fabrication of high performance supercapacitor devices. [ABSTRACT FROM AUTHOR]

In this study, a pulse-mode electrochemical deposition technique was employed to deposit dense and homogeneous Ni nanoparticles on the three-dimensional graphene network (3DGN) as the catalysts for growing the vertical aligned one-dimensional carbon nanofibers (CNFs) to fabricate the full-carbon hybrid nanoarchitecture of CNFs/3DGN for the supercapacitors. When tested as electrode for a supercapacitor, the CNFs/3DGN hybrid nanoarchitecture demonstrated to possess a large surface area and showed an excellent specific capacitance of 59.28 F g −1 at a current density of 0.17 mA cm −2 , also displayed good cycle stability with capacitance retention of 93.9% after 10,000 cycles in 6 M KOH electrolyte. [ABSTRACT FROM AUTHOR]

A new kind of porous carbon nanofiber networks has been synthesized via electrospinning technique by using polyacrylonitrile and asphalt as carbon sources and Pluronic F127 as soft template. After stabilization and carbonization treatment, the obtained fabrics were directly utilized as self-supported anode materials for sodium-ion batteries. This kind of porous carbon nanofiber exhibits excellent sodium-ion storage properties, with a reversible capacity of 210 mA h g −1 at current density of 500 mA g −1 after 1000 cycles. [ABSTRACT FROM AUTHOR]

Porous N-doped carbon nanofibers derived from polydopamine are fabricated by a facile carbonized technique and a subsequent template-removing process. Superior to the other porous carbon nanomaterials that voids are directly exposed in the electrolyte, the nanopores in our designed nanofibers are confined by the inner carbon walls and outer carbon shells. The prepared porous N-doped carbon nanofibers electrode shows high reversible capacities of 1324 mAh g −1 after 150 cycles at 0.2 A g −1 and 780 mAh g −1 after 500 cycles at 1 A g −1 . [ABSTRACT FROM AUTHOR]

The great demand for high-power lithium-ion batteries (LIBs) has spurred extensive research on carbonaceous electrode materials. In this work, a novel high nitrogen-doped helical carbonaceous nanofiber derived from pyrolytic resins was fabricated. Helical m-phenylenediamine-formaldehyde resin nanotubes were prepared via a sol-gel duplication method using a chiral amphiphile as the template. Then, the obtained resin nanotubes were subject to carbonize at 600 °C under Ar atmosphere, forming helical carbonaceous nanofibers with N content of 12.4 wt%. The inner tunnels were disappeared owing to the thermal contraction. Wide angle X-ray diffraction and Raman spectrum analysis verify that the obtained nanofibers were amorphous carbon predominantly. The electrochemical characterization reveals that the in-situ nitrogen-doped carbonaceous nanofibers exhibit high specific capacity, together with long cycle time and excellent rate capability. [ABSTRACT FROM AUTHOR]

The ultimate goal of this study was to further improve tensile properties of continuous bundles of highly aligned carbon nanofibers. The hypothesis was that adopting moderate tension during carbonization could improve the formation and orientation of graphite crystallites, leading to increased tensile properties of carbon nanofibers. In this study, bundles consisting of highly aligned PAN copolymer nanofibers were first prepared by electrospinning and collected via a flowing water bath, followed by 3-time stretching and oxidative stabilization. The stabilized PAN nanofibers were then carbonized under tensions of 10–50 cN which corresponding to 254.7–1273.5 MPa, respectively. The effects of carbonization tension on structural and tensile properties of carbon nanofibers were investigated by WAXD, Raman spectroscopy and filament specimen methods. The results indicated that the orientation of graphite crystallites in carbon nanofibers could be improved by increasing carbonization tensions from 254.7 MPa to 509.4 MPa; and the highest tensile strength and modulus of carbon nanofibers could reach 1115 MPa and 194.5 GPa, respectively. [ABSTRACT FROM AUTHOR]

Cellulose acetate (CA), with an easily controlled morphology in the production of nanofibers, requires deacetylation to produce carbon nanofibers (CFs). In this study, electrospun CA nanofibers were deacetylated by fluorination. In mild fluorination, CA nanofiber and fluorinated CA nanofibers had similar fiber morphologies. However, in extreme fluorination conditions, CA nanofibers were aggregated. Fluorination caused deacetylation and introduced fluorine functional groups to the CA nanofibers. Deacetylation of the CA nanofibers prevented the fibers from melting during the carbonization process. The introduced fluorine functional groups increased the thermal stability and carbonization yield of the CA nanofibers. These results suggest that fluorination is an effective deacetylation method for CFs from CA nanofibers. [ABSTRACT FROM AUTHOR]

• CoNi 2 S 4 -CNF composite has been prepared via a novel one-pot synthetic strategy. • The introduction of CNF prevents the agglomeration of CoNi 2 S 4 and CNF. • The capacitance retention of the hybrid supercapacitor is 76.6% after 5000 cycles. • The enhanced capacitive performance is ascribed to the unique heterostructure. A novel CoNi 2 S 4 nanoparticle-loaded carbon nanofiber (CoNi 2 S 4 -CNF) composite has been prepared via a facile one-pot synthetic strategy. In the composite, CoNi 2 S 4 nanoparticle is intimately contact with CNF, which is beneficial for improving the electrochemical performance. The specific capacitance of CoNi 2 S 4 -CNF is 1053.3, 968.7, 893.4 and 841.7F g−1 at 4, 6, 8, 10 A g−1, respectively, which is higher than CoNi 2 S 4. Electrochemical impedance spectroscopy result indicates that the combination of CoNi 2 S 4 and CNF can decrease the electrochemical reaction resistance efficiently. Moreover, the hybrid super-capacitor assembled by the CoNi 2 S 4 -CNF cathode and the activated carbon anode demonstrates a specific capacitance of 111.1F g−1 at 0.5 A g−1. [ABSTRACT FROM AUTHOR]