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In this study, nano-sized SnO2 decorated on carbon cloth (SnO2/CC) is prepared through a simple and facile solid method. The nano-sized SnO2 is uniformly distributed on the surface of carbon fibers in carbon cloth, providing sufficient free space to relieve volume expansion and reduce electrode pulverization during cycling. The as-prepared SnO2/CC as a flexible, self-supporting and additive-free anode electrode for sodium-ion/lithium-ion batteries (SIBs/LIBs) can demonstrate outstanding electrochemical performance. SnO2/CC after annealing at 350 °C (SC-350) as an anode for SIBs can deliver a reversible capacity of 0.587 mA h cm−2 at the current density of 0.3 mA cm−2 after 100 cycles. In addition, when cycling at 1.5 mA cm−2, SC-350 can maintain 1.69 mA h cm−2 after 500 cycles when used as LIB anode. These results illustrate that the as-prepared SnO2/CC can be a promising flexible anode material for flexible SIBs/LIBs and provide a simple and practical method for designing new flexible electrode materials.

Achieving fast-charging/discharging (FCD) performance for sodium-ion batteries (SIBs) has always been a great challenge, because of their slow reaction kinetics and the difficulty in ensuring the stability of the electrode during sodiation/desodiation. In this study, a hypoxic graphene (HG) is rationally designed and prepared using a simple high temperature treatment process. It is confirmed that the hypoxic surface is more conducive to the rapid conduction of electrons and forming a high quality SEI film in the first cycle to avoid irreversible side reactions. Furthermore, a versatile electrolyte suitable for improving the FCD performance of different carbon materials is screened and used in this system. As a result, the best sample of HG-1300 shows almost full pseudocapacitive behavior as an anode material for SIBs, and exhibits a super FCD performance (110 mA h g−1 at an ultrahigh current density of 200 A g−1, only 4 seconds per cycle) and ultralong lifespan (90.7% capacity retention over 100 000 cycles at 20 A g−1), even surpassing supercapacitors.

The graphite material from exhausted Li-ion batteries (LIBs) is reused as a favorable anode for Na-ion batteries (NIBs) and K-ion batteries (KIBs) through a recycling treatment. The optimized electrode delivers improved electrochemical performance, such as 162 mA h g−1 in NIBs at 0.2 A g−1 and 320 mA h g−1 in KIBs at 0.05 A g−1. In addition, the insights into Na/K-ion de-/intercalation model evolution and corresponding electrochemical analysis are conducted through in operando X-ray diffraction and a series of other characterization methods, discovering a visible transitional stage for NIBs and an irreversible initial cycle phase transformation for KIBs. In a word, we not only provide a new recycling concept for waste graphite anodes but also carry out a series of significant intercalation mechanism studies, which contribute to anode recycling and shed light on the development of graphite material for promising alternative ion batteries.

Owing to the high de/intercalation potential of anions on graphite cathode, dual-ion battery (DIB) has attracted much attention for advanced energy storage. Among various DIBs, Li//graphite (Li//G)...

Due to the Earth’s scarcity of lithium, replacing lithium with earth-abundant and low-cost sodium for sodium-ion batteries (SIBs) has recently become a promising substitute for lithium-ion batterie...

In order to ascertain the effect of carbon networks with various dimension on the Li-storage properties of Fe 3 O 4 anode material, three Fe 3 O 4 -based nanocomposites with different dimensional carbon networks, including zero-dimensional C/Fe 3 O 4 (0D-C/F), one-dimensional carbon nanotubes/Fe 3 O 4 (1D-CNTs/F) and two-dimensional graphene/Fe 3 O 4 (2D-G/F) nanocomposites, are successfully prepared via precisely controlling the preparation processes and parameters. Their morphology, conductivity, reaction kinetics, and electrochemical properties are discussed in detail. The results show that the addition of 1D-CNTs or 2D-G in the Fe 3 O 4 results in a smaller size of Fe 3 O 4 particles, which shortens the diffusion distance of Li + , and provides a faster electron conduction pathways, as well as the flexible carbon networks will effectively relieve the internal strain during charge and discharge processes. Most importantly, it is revealed that 2D-G/F with the large surface area leads to a faster electrochemical reaction kinetic which is mainly controlled by pseudocapacitive behavior, while the electrochemical reaction kinetic of 1D-CNTs/F is dominated by the slow Li + insert process. As a result, 2D-G/F shows the best Li-storage performance with a reversible capacity of 1014 mAh g −1 in the first cycle at 0.1 C and even at a high rate of 5 C, the reversible capacity is still 513.5 mAh g −1 . Furthermore, after 100 cycles at 0.5 C, it still delivers a reversible capacity of 1125.6 mAh g −1 without capacity decay.

As a promising anode candidate for lithium ion batteries (LIBs), MnO has attracted wide attentions owing to its theoretically high Li-storage capacity, lower working voltage and polarization than other oxides, low cost, environmental friendliness, and abundant resources. Herein, we develop a facile and low-cost strategy to fabricate a unique porous MnO@N-doped carbon (MnO@N-C) nanotube and demonstrate its outstanding Li-storage properties as anode material for LIBs. Benefiting from its unique 1D porous features, the prepared MnO@N-C electrodes exhibit high reversible specific capacity (971.8 mAh g−1 at 0.1 A g−1), superb high-rate capability (359.5 mAh g−1 at 30 A g−1) and remarkable cycling stability (441.5 mA h g−1 after 3500 cycles at 10 A g−1). Such superior electrochemical performance should be due to the high conductivity and protection effects of N-doped carbon layer, and adequate internal voids in the MnO@N-C to effectively accommodate the volume changes of MnO during cycling. In addition, it is also disclosed that the high capacity contribution arises from the pseudocapacitive charge storage.

A novel core–shell Fe3O4@FeS composed of Fe3O4 core and FeS shell with the morphology of regular octahedra has been prepared via a facile and scalable strategy via employing commercial Fe3O4 as the precursor. When used as anode material for sodium-ion batteries (SIBs), the prepared Fe3O4@FeS combines the merits of FeS and Fe3O4 with high Na-storage capacity and superior cycling stability, respectively. The optimized Fe3O4@FeS electrode shows ultralong cycle life and outstanding rate capability. For instance, it remains a capacity retention of 90.8% with a reversible capacity of 169 mAh g–1 after 750 cycles at 0.2 A g–1 and 151 mAh g–1 at a high current density of 2 A g–1, which is about 7.5 times in comparison to the Na-storage capacity of commercial Fe3O4. More importantly, the prepared Fe3O4@FeS also exhibits excellent full-cell performance. The assembled Fe3O4@FeS//Na3V2(PO4)2O2F sodium-ion full battery gives a reversible capacity of 157 mAh g–1 after 50 cycles at 0.5 A g–1 with a capacity retention of...

In this article, an effective strategy (viz., constructing multiple heterointerfaces) is proposed to develop superior electrode materials for sodium-ion battery (SIB), which is the most promising alternative to market-dominant lithium-ion battery for stationary energy storage. In the as-prepared heterogeneous-SnO2/Se/graphene (h-SSG) composite, there exists multiple phase interfaces, including heterointerfaces between tetragonal and orthorhombic SnO2 (t-/o-SnO2) in the heterogeneous SnO2 nanojunctions and two phase interfaces between t/o-SnO2 and amorphous Se. These multiple phase interfaces promise the much improved Na storage properties of h-SSG when compared to four controls without such multiple heterointerfaces because the multiple built-in electric fields at the heterointerfaces can significantly boost the surface reaction kinetics and facilitate charge transport as demonstrated by kinetics analyses, theoretical calculations and contrastive electrochemical tests. Moreover, h-SSG also exhibits superior Na-ion full cell performance when coupled with a high-voltage Na3V2(PO4)2O2F cathode. In view of the universality of the heterointerface-based enhancement effect on surface reaction and charge transport kinetics and the facile preparation procedures, the present strategy should be universal to develop other superior electrode materials for high-performance SIBs and other batteries for future energy storage applications.

In this study, the double transition metal selenide Ni1.5CoSe5 with cube-like nanoaggregate morphology was successfully embedded into a three-dimensional (3D) dual N-doped carbon network, developing an advanced anode material for sodium-ion batteries (SIBs). In the prepared composite, Ni1.5CoSe5 nanoparticles were first coated by N-doped carbon (NC), which further aggregated to form nanocubes, and finally embedded into interconnected N-doped reduced graphene oxide (rGO) nanosheets; hence, the material was abbreviated as Ni1.5CoSe5@NC@rGO. It delivered a reversible Na-storage capacity of 582.5 mA h g−1 at a low current density of 0.05 A g−1 and exhibited ultra-fast rate properties (e.g., with the specific capacities of 180.8 and 96.3 mA h g−1 at high current densities of 30 and 50 A g−1, respectively). The much enhanced Na-storage properties were ascribed to the highly conductive 3D network constructed by dual N-doped carbonaceous materials, which acted not only as a highway for ultrafast charge transfer but also as an effective protector for the active Ni1.5CoSe5 material and cube-like nanoaggregates with nanometer-sized primary particles. More significantly, the Ni1.5CoSe5@NC@rGO electrode also exhibited superior energy storage performance in sodium-ion full cells when coupled with a high-voltage Na3V2(PO4)2O2F cathode, making it a promising anode material for practical SIBs.

Recently, sodium-ion batteries (SIBs) have been considered as the promising alternative for lithium-ion batteries. Although layered P2-type transition metal oxides are an important class of cathode materials for SIBs, there are still some hurdles for the practical applications, including low specific capacity as well as poor cycling and rate properties. In this study, the electrochemical properties of layered Mn-based oxides have been effectively improved via Al doping, which cannot only promote the formation of layered P2-type structure in the preparation processes but also stabilize the lattice during the successive Na-intercalation/deintercalation due to suppression of the Jahn-Teller distortion of Mn3+. Among the as-prepared series of Na2/3Mn1-xAlxO2 (x = 0, 1/18, 1/9, and 2/9), Na2/3Mn8/9Al1/9O2 with x = 1/9 exhibits the optimal doping effect with the best electrochemical properties, in terms of the highest specific capacity of 162.3 mA h g−1 at 0.1 C, the highest rate capability, and the best cycling stability in comparison to the undoped Na2/3MnO2 and the other two materials with different Al-doped contents. Both cyclic voltammetry at varied scan rates and galvanostatic intermittent titration technique disclose the optimal electrode kinetics (the highest Na-diffusion coefficient) of the best Na2/3Mn8/9Al1/9O2.

Metallic lithium protection plays a crucial role on improving the electrochemical properties of Li-anode-based batteries. Herein, for an advanced Li//graphite dual-ion battery, constructing a robust and conductive film of carbon nanofibers on a Li anode effectively achieves dendrite-free Li growth and hence significantly enhances the long-life cyclic stability.

With the rapidly increasing use of lithium ion batteries (LIBs), the corresponding spent materials will eventually lead to severe environment pollution and resource waste if they cannot be recycled...

An advanced hierarchically porous nanosheets-constructed three-dimensional (3D) carbon material (HPNSC) is prepared by using low-cost agricultural waste-nelumbium seed-pods as the precursor, and potassium hydroxide (KOH) as the activator. The as-prepared HPNSC material has a hierarchically porous nanosheets-constructed structure with 3D carbon nanosheet network morphology, which can enable fast and efficient transfer of Li+/Na+/H+ during charge-discharge process. The assembled HPNSC//HPNSC symmetric supercapacitors exhibit an improved energy density of 41.3 W h kg-1 with a power density of 180 W kg-1 in 1 mol l-1 Na2SO4 electrolyte. The energy density can still be maintained at 16.3 W h kg-1 even if the power density is increased to 9000 W kg-1. When acting as the reversible electrode for lithium ion batteries, this HPNSC material can achieve a high specific capacity of 1246 mA h g-1 at 0.1 A g-1. Moreover, sodium ion battery with HPNSC electrode exhibits excellent cycling performance of 161.8 mA h g-1 maintained even after being cycled 3350 times. The electrochemical performances clearly indicate that the HPNSC developed in this work is a very promising energy storage electrode material, and can further provide new insights for designing and developing highly porous materials for energy storage in other fields.

In order to develop promising anode materials for lithium-ion batteries (LIBs), a unique nanocomposite abbreviated as G⊥FP@C-NA, in which a carbon-coated FeP nanorod array (FP@C-NA) is vertically grown on a conductive reduced graphene oxide (G) network, has been successfully prepared via a scalable strategy. Benefiting from the distinctive structure, G⊥FP@C-NA exhibits much improved conductivity, structural stability and pseudocapacitance-boosted ultrafast electrochemical kinetics for Li storage. As a result, the G⊥FP@C-NA delivers a high Li-storage capacity (1106 mA h g-1 at 50 mA g-1), outstanding rate capability (565 mA h g-1 at 5000 mA g-1) and long-term cycling stability (1009 mA h g-1 at 500 mA g-1 after 500 cycles and 310 mA h g-1 at 2000 mA g-1 after 2000 cycles) when used as an anode material for LIBs. As expected, this kind of nanoarray structure is attractive and can also be extended to other electrode materials for various energy storage systems.

In this work, the low-cost hierarchically porous nitrogen-doped carbon nanosheets (PNCNs) were prepared via one-step carbonization and KOH activation process of grapefruit peels. The prepared PNCNs exhibit higher specific surface area due to the inducement of the KOH-assisted carbonization compared to directly carbonized grapefruit peels (DCGPs). The PNCNs exhibit excellent electrochemical performances with high specific capacitance up to 311 F g−1, superior cycling stability over 10000 cycles with only 5.95 % capacitance degradation, high energy density of 17.7 W h kg−1 and power density of 1100 W kg−1 in 1 mol L−1 H2SO4 electrolyte. All these electrochemical data are significantly better than the comparative DCGPs material. Moreover, the assembled symmetric supercapacitor in 1 mol L−1 Na2SO4 aqueous electrolyte exhibits a high energy density of 34.05 W h kg−1 at a power density of 180 W kg−1 and retains 14.25 W h kg−1 even at 5400 W kg−1.

Dual-carbon enhanced Si-based composite (Si/C/G) has been prepared via employing the widely distributed, low-cost and environmentally friendly Diatomite mineral as silicon raw material. The preparation processes are very simple, non-toxic and easy to scale up. Electrochemical tests as anode material for lithium ion batteries (LIBs) demonstrate that this Si/C/G composite exhibits much improved Li-storage properties in terms of superior high-rate capabilities and excellent cycle stability compared to the pristine Si material as well as both single-carbon modified composites. Specifically for the Si/C/G composite, it can still deliver a high specific capacity of about 470 mAh g−1 at an ultrahigh current density of 5 A g−1, and exhibit a high capacity of 938 mAh g−1 at 0.1 A g−1 with excellent capacity retention in the following 300 cycles. The significantly enhanced Li-storage properties should be attributed to the co-existence of both highly conductive graphite and amorphous carbon in the Si/C/G composite. While the former can enhance the electrical conductivity of the obtained composite, the latter acts as the adhesives to connect the porous Si particulates and conductive graphite flakes to form robust and stable conductive network.

Due to the Earth's scarcity of lithium, replacing lithium with earth-abundant and low-cost sodium for sodium-ion batteries (SIBs) has recently become a promising substitute for lithium-ion batteries. However, the shortage of appropriate anode materials limits the development of SIBs. Here, a dual-carbon conductive network enhanced GeP

In order to develop promising anode materials for sodium-ion batteries (SIBs), a novel pie-like FeS@C (P-FeS@C) nanohybrid, in which all ultrasmall FeS nanocrystals (NCs) are completely embedded into the carbon network and sealed by a protective carbon shell, has been prepared. The unique pie-like structure can effectively speed up the kinetics of electrode reactions, while the carbon shell stabilizes the FeS NCs inside. Studies show that the electrochemical reaction processes of P-FeS@C electrodes are dominated by the pseudocapacitive behavior, leading to an ultrafast Na+-insertion/extraction reaction. Hence, the prepared P-FeS@C nanohybrid exhibits superior Na-storage properties especially high rate capability in half cells. For example, it can deliver reversible capacities of 555.1 mA h g−1 at 0.2 A g−1 over 150 cycles and about 60.4 mA h g−1 at 80 A g−1 (an ultrahigh current density even higher than that of the capacitor test). Furthermore, an advanced P-FeS@C//Na3V2(PO4)2O2F full cell has been assembled out, which delivers a stable specific capacity of 441.2 mA h g−1 after 80 cycles at 0.5 A g−1 with a capacity retention of 91.8%.

In recent years, graphene-incorporated micro-/nanocomposites represent one of the hottest developing directions for the composite materials. However, a large number of active nanoparticles (NPs) are still in the unprotected state in most constructed graphene-containing designs, which will seriously impair the effects of the graphene additives. Here, a fully protected Fe3O4-based micro-/nanocomposite (G/Fe3O4@C) is rationally developed by carbon-boxing the common graphene/Fe3O4 microparticulates (G/Fe3O4). The processes and results of full protection are tracked in detail and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and nitrogen absorption–desorption isotherms, as well as scanning and transition electron microscopy. When used as the anode for lithium-ion batteries, the fully protected G/Fe3O4@C exhibits the best lithium-storage properties in terms of the highest rate capabilities and the longest cycle life compared to the common G/Fe3O4 composites and commercial Fe3O4 products. These much improved properties are mainly attributed to its novel structural features including complete protection of active Fe3O4 nanoparticles by the surface carbon box, a robust conductive network composed of nitrogen-doped graphene nanosheets, ultra-small Fe3O4 NPs of 4–5 nm, abundant mesopores to accommodate the volume variation during cycling, and micrometer-sized secondary particles.

Although a wide variety of biomass, such as human hair, chicken eggshells and ox horns, have been used to prepare carbon electrode materials for energy storage, most of them have very limited production, which restricts their large-scale application. Herein, the very prolific biomass of chitosan is employed as an abundant raw material to successfully prepare one porous N-doped carbon material (PNCM). Structural characterizations demonstrate that this PNCM is hierarchically porous with abundant macro/micropores and 4.19% N-doping. The electrochemical properties of the PNCM as electrode materials for both supercapacitors and lithium ion batteries are also studied. When used in a supercapacitor, the optimized PNCM synthesized at 700 °C can store electrical energy with a specific capacitance of up to 220 F g−1 in 1 mol L−1 H2SO4 electrolyte, exhibit excellent cycle stability with only 1.3% capacitance decay over 11 000 cycles, and deliver high power and energy densities in both aqueous and organic electrolytes. In addition to supercapacitors, the PNCM also exhibits excellent Li-storage properties in terms of high specific capacity (above 460 mA h g−1 at 50 mA g−1) and superior cycle stability (without any capacity decay even after 1100 cycles) when used as an anode material for lithium ion batteries.

Among the transition metal oxides as anode materials for lithium ion batteries (LIBs), the MnO material should be the most promising one due to its many merits mainly relatively low voltage hysteresis. However, it still suffers from inferior rate capabilities and poor cycle life arising from kinetic limitations, drastic volume changes and severe agglomeration of active MnO particulates during cycling. In this paper, by integrating the typical strategies of improving the electrochemical properties of transition metal oxides, we had rationally designed and successfully prepared one superior MnO-based nanohybrid (MnO@C/RGO), in which carbon-coated MnO nanoparticles (MnO@C NPs) were electrically connected by three-dimensional conductive networks composed of flexible graphene nanosheets. Electrochemical tests demonstrated that, the MnO@C/RGO nanohybrid not only showed the best Li storage performance in comparison with the commercial MnO material, MnO@C NPs and carbon nanotube enhanced MnO@C NPs, but also exhibited much improved electrochemical properties compared with most of the previously reported MnO-based materials. The superior electrochemical properties of the MnO@C/RGO nanohybrid included a high specific capacity (up to 847 mA h g−1 at 80 mA g−1), excellent high-rate capabilities (for example, delivering 451 mA h g−1 at a very high current density of 7.6 A g−1) and long cycle life (800 cycles without capacity decay). More importantly, for the first time, we had achieved the discharging/charging of MnO-based materials without capacity increase even after 500 cycles by adjusting the voltage range, making the MnO@C/RGO nanohybrid more possible to be a really practical anode material for LIBs.

Hard carbon is regarded as a promising anode material for sodium-ion batteries (SIBs). However, it usually suffers from the issues of low initial Coulombic efficiency (ICE) and poor rate performance, severely hindering its practical application. Herein, a flexible, self-supporting, and scalable hard carbon paper (HCP) derived from scalable and renewable tissue is rationally designed and prepared as practical additive-free anode for room/low-temperature SIBs with high ICE. In ether electrolyte, such HCP achieves an ICE of up to 91.2% with superior high-rate capability, ultralong cycle life (e.g., 93% capacity retention over 1000 cycles at 200 mA g-1 ) and outstanding low-temperature performance. Working mechanism analyses reveal that the plateau region is the rate-determining step for HCP with a lower electrochemical reaction kinetics, which can be significantly improved in ether electrolyte.

To discuss the surgical option and the treatment of complications of pancreatic cystic tumors.From January 1997 to December 2009, 32 patients with pancreatic cystic tumors in our center were reviewed retrospectively. There were 6 male and 26 female, aging from 24 to 76 years. Of the 32 patients, 16 patients had serous cystadenoma, 9 patients had mucinous cystadenoma; 1 patients had mucinous cystadenocarcinoma; 4 patients had intraductal papillary mucinous neoplasms and 3 patients had pancreatic solid pseudopapillary neoplasms. Tumor located in pancreatic head in 12 patients and in pancreatic body and tail in 20 patients.All patients received surgical treatment and there was no perioperative death. Pancreato-duodenectomy was performed in 10 patients, duodenum-preserving pancreatic head resection in 1 patient, distal pancreactomy in 13 patients, including laparoscopic distal pancreactomy in 2 patients, pancreatic tumor resection in 3 patients, middle segmental resection in 4 patients; 1 patients with mucinous cystadenocarcinoma received palliative surgery. Complication included gastroparesis in 3 patients and pancreatic fistula in 5 patients, and all recovered by conservative treatment. These 29 patients were followed up 4 - 120 months, 3 patients died from tumor metastasis or other disease within 4 to 34 months after surgery. Others were alive and there was no tumor recurrence or metastasis.CT scan should be the first choice of non-invasive examination for cystic pancreatic diagnosis. Positive and timely operation should be performed in the patient with cystic pancreatic tumor, and it acts as a cancer preventive treatment. The selection of surgical approach should be individualized, the principal of damage control surgery should be followed. Complications such as gastroparesis and pancreatic fistula should be paid more attention.

To evaluate the clinical value of perioperative adjuvant chemotherapy in prevention of tumor recurrence and improvement of patient survival after liver transplantation for advanced hepatocellular carcinoma (HCC).Twenty patients with advanced HCC (pTNM stages III and IV a) receiving liver transplantation with preoperative transcatheter arterial chemoembolization (TACE) and postoperative adjuvant chemotherapy (ADM+5-Fu+CDDP) were retrospectively reviewed in comparison with 16 patients receiving liver transplantation only for tumor recurrence, cumulative and tumor-free survivals. The feasibility and side-effects of the treatments were also studied.The recurrence rate was lower in the perioperative treatment group than in non-treatment group (12/20, 60.0% vs 11/16, 87.5%, P0.05). The 1- and 2-year overall survival rates were 70.8% and 47.1% for the chemotherapy group and 43.8% and 20.5% for the non-chemotherapy group respectively, showing significant differences between them (P0.05). The 1- and 2-year tumor-free survival rates were 60.6%, 40.5% and 33.6%, 15.6% in the two groups, respectively, with also significant differences (P0.05).Perioperative adjuvant treatment may significantly decrease the likeliness of tumor recurrence and prolong the survival of patients with advanced HCC after liver transplantation. Chemotherapy with ADM+5-Fu+CDDP can be effective and safe with only mild side-effects.

To evaluate the effect of perioperative HLA antibody changes on acute allograft rejection in cadaveric liver transplantation.Totally 134 patients received modified piggyback liver transplantation and enzyme-linked immunosorbent assay was performed for HLA antibody detection before and the 1, 7, 14 and 30 days after operation. B ultrasound-guided liver biopsy was employed for diagnosis of acute allograft rejection, and the perioperative changes of HLA antibodies were evaluated for their effect on allograft acute rejection.Of the 44 recipients with preoperative positivity for HLA antibodies, acute rejection occurred in 56.8% of the patients, as compared with 25.9% in those negative for HLA antibody (P=0.001). The patients who became positive for HLA antibody postoperatively had a rate of acute rejection of 60%, which was significantly higher than that in those persistently negative for HLA antibody (18.6%, P=0.003).HLA antibody positivity before transplantation may contribute to acute rejection episode in liver transplantation, and persistent posttransplant HLA antibody positivity is closely associated with the occurrence of acute rejection.