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The development of advanced cathode materials with high operational voltage and high reversible capacity is crucial for facilitating the practical realization of sodium-ion battery (SIB) technology. Herein, O3-type Na0.9Ca0.035Cr0.97Ti0.03O2 is designed by co-substitution of Ca and Ti into O3-type NaCrO2, and proposed as a new cathode material for high-energy and practical SIBs. On the basis of the stoichiometry, alkali earth metal ions successfully incorporate into the NaO6 octahedron of NaCrO2 by substituting a single Ca2+ per two Na+, while Ti4+ ions are substituted with Cr3+ ions into the CrO6 octahedral site, resulting in formation of Na+ vacancies in the Na+ layer for the charge compensation. This co-substitution strategy reinforces the structural stability of the O3-type Na0.9Ca0.035Cr0.97Ti0.03O2 cathode, induced by the stronger Ti–O bond than Cr–O bond and presence of immobile Ca2+ ions between the CrO6 slabs. These structural features suppress the irreversible phase transition and provide excellent Na+ ion-diffusion kinetics in a wide operation voltage window of 1.5–3.8 V, allowing the cathode to deliver the high initial Coulombic efficiency of 95% and retain the 90% of its initial capacity after 1000 cycles at a 10 C rate. Moreover, the cathode guarantees the practical applicability with long-term cycling in a pouch-type full cell using a hard carbon anode, as well as with durability against water.

The origin of parasitic reaction formed/dissolved during the electrochemical reaction at the interface and the conformity role of H+/H2O carrier during electrochemical reaction in aqueous Zn salt electrolyte medium of aqueous rechargeable zinc-ion batteries (ARZIBs), is almost recognized halfway; albeit the consequence of this side reaction is not established yet. Through operando X-ray diffraction analyses in two different electrolytes, the parasitic phases and the dual carriers are recognized in a hyper non-stoichiometry layered oxide of V6O13+x.nH2O as cathode. Indeed, galvanostatic intermittent titration (GITT) and operando potentiostatic electrochemical impedance spectroscopy (PEIS) techniques are utilized to clearly show the parasitic phase of thick ZBS (zinc basic sulfate) layer negatively influence the reaction kinetics at the interface in ZnSO4 electrolyte and hence the performance, especially at low current surges. Thus, the layered cathode demonstrated exceptional stability especially in Zn (CF3SO3)2 electrolyte. For example, in a 1 M ZnSO4/1 M Zn (CF3SO3)2 aqueous electrolyte, nearly 80/65% capacity retention over 2,000/5000 cycles at 15 C is exhibited. Comparative GITT investigations on the overpotential and electrochemical kinetics in ZnSO4 and water electrolytes offer strong evidence for the continuous and reversible co-intercalation of dual carriers of Zn2+and H+/H2O.

The development of new battery technologies requires to be well established in the same era of lithium ion batteries (LIBs), a well commercialized technology, and the merits should surpass over oth...

Package structures are continually becoming more complicated to achieve high-performance devices. Thus, the 2D structure of package needs to be modified to a 2.5D or 3D structure. Therefore, standoff properties at the solder joint are required to prevent Si chip damage and electrical shorts when the solder joint is located between the substrate and interposer. Cu-core solder balls (CCSB) are the most popular interconnection choice for a 2.5D package because they have better standoff properties than the general SAC solder. The mechanical properties of CCSBs were evaluated by ball shear tests and measuring bump height as compared with Sn–3.0 wt.%Ag–0.5 wt.% Cu solder. The bump heights of CCSBs and Sn–3.0 wt.%Ag–0.5 wt.% Cu were measured under several compressive pressure conditions at room temperature, 175 °C and 235 °C. The stand-off height of the CCSBs dramatically better than that of Sn–3.0 wt.%Ag–0.5 wt.% Cu solder under high pressure and temperature. The shear strength of the CCSBs was stronger than that of SAC solder at all multiple reflows due to the finer microstructure and higher stacking of dislocations at the interface of the Cu core ball surface.

Transition-metal sulfides are of significant interest as rechargeable battery anodes owing to their low cost, wide availability, eco-friendliness, and high theoretical capacities. However, extraordinary structural changes in these materials cause pulverization of the electrode, thereby limiting their practical electrochemical abilities. Herein, a simple one-pot polyol refluxing method is used for fabricating a manganese sulfide (MnS) electrode composited with nitrogen and sulfur co-doped carbon (MnS@NS-C) for high-power lithium-ion batteries. This electrode exhibits unique spherical particle morphology with optimized average particle size (300 < x < 500 nm) and porous features. Owing to its nanostructure, porous nature, and an electrically conducting carbon network co-doped with heteroatoms, the composite electrode overcomes the strong structural variations to afford high practical storage capacities, long-term cycle stability, and outstanding rate capability. The MnS@NS-C electrode demonstrated high reversible storage capacities of 999 mA h g−1 at 0.1 A g−1, the highest reversible capacity of 761 mA h g−1 at 2 A g−1 for over 300 cycles, and average rate capacities of 453 mA h g−1 at 10 A g−1. In situ synchrotron X-ray diffraction investigations indicated a uniquely combined intercalation-cum-conversion reaction mechanism leading to β-Li2(1−x)MnS, Li2S, and Mn discharge products. The results of this study can provide deep insights into understanding intriguing reactions and motivate further study of transition-metal sulfides for prospective high-energy battery applications.

Sodium-ion batteries (SIBs) have attracted great attention for day-to-day applications as a replacement for lithium-ion batteries (LIBs) that deliver high voltage and high energy because of the low battery-preparation cost and vast availability of sodium resources. The recent exploration of Na+ superionic conductor or NASICON-type Na4VMn(PO4)3 (NVMP) cathodes for SIBs is a pioneering approach because of the high working voltage, high theoretical capacity, and stable three-dimensional framework of the NVMP cathodes. However, the inherently low electronic conductivity results in mediocre rate outputs and poor exploitation of the active material. Herein, we report, for the first time, the preparation of a cotton candy-like carbon-coated Cu-doped NVMP or Na4VMn0.9Cu0.1(PO4)3 (NVMCP/C/CC) cathode by a facile and ultrafast pyro-synthetic method. The robust structure of the NVMCP/C/CC and the highly reversible two-phase reaction upon Na-ion insertion/extraction were systematically revealed by the in situ synchrotron XRD and GITT studies, while the DFT calculations established the crucial reasons behind the enhanced electronic conduction of the NVMCP/C/CC. The superior electrochemical properties of the NVMCP/C/CC cathode at low (79 mA h g−1 after 450 cycles at 1.5C) and high current rates (68 mA h g−1 after 3000 cycles at 30C) demonstrate that the combination of a three-dimensional nanoarchitecture, uniform carbon-coating, and Cu-doping is favorable for improving the electrochemical properties of the NVMP cathodes.

Polyamidoamine (PAMAM) dendrimer is one of the cationic polymers widely used in nonviral vector-based gene therapy. As PAMAM comprises biodegradable peptide bonds, it shows biocompatibility and relatively low cytotoxicity. In comparison with polyethylenimine (PEI, 25 kDa) that shows high transfection efficiency, the native PAMAM dendrimer has limitations as a gene carrier. To improve the gene expression efficiency, we introduced KRTR peptides derived from the influenza B virus nucleoprotein, known as a nuclear localization signal (NLS), to PAMAM generation 3. We synthesized PAMAM-RTRK and PAMAM-HRTRK and evaluated the effects of the histidine residue on cytotoxicity. The transfection efficiency of PAMAM-RTRK and PAMAM-HRTRK was similar to that of PEI in HepG2 cells, while their gene expression capacities were much higher than capacity of PEI in A549 cells. PAMAM-HRTRK showed relatively lower cytotoxicity than PAMAM-RTRK in the two cell lines, but the transfection capacity was similar for the two polymers. These results imply that the combination of histidine and KRTR peptide may potentially result in a novel PAMAM-based vector that could be used for prolonged gene therapy through the reduction in cytotoxicity and enhancement of gene expression.

Aqueous rechargeable zinc-ion batteries (ARZIBs) have drawn enormous attention because of their low-cost and eco-friendly cell components. However, designing high-performance cathode materials towards practical application of ARZIBs remains a major challenge. Therefore, in this contribution, a comprehensive study on K+ intercalated V2O5 (KVO) nanorods with exposed facets as a high-performance cathode for ARZIBs is presented. The KVO cathode exhibits remarkable discharge capacities of 439 and 286 mAh g−1 at current densities of 50 and 3000 mA g−1, respectively. Furthermore, it recovers 96% of the capacity after 1500 cycles at 8000 mA g−1. Impressively, the Zn/KVO battery offers a specific energy of 121 W h kg−1 at high specific power of 6480 W kg−1. The storage mechanism of the KVO cathode in an ARZIB is systematically elucidated using in operando synchrotron X-ray diffraction, ex situ synchrotron X-ray absorption spectroscopy, ex situ TEM analyses and first-principles calculations. The superior performance of the cathode is attributed to its unique exposed layer structure with high surface energy, high conductivity and low migration barrier for Zn2+ migration. This study provides insight into designing high-performance cathode materials for ARZIBs and other electrochemical systems.

Manganese (Mn)‐based cathode materials have garnered huge research interest for rechargeable aqueous zinc‐ion batteries (AZIBs) due to the abundance and low cost of manganese and the plentiful advantages of manganese oxides including their different structures, wide range of phases, and various stoichiometries. A novel in situ generated Mn‐deficient ZnMn2O4@C (Mn‐d‐ZMO@C) nanoarchitecture cathode material from self‐assembly of ZnO‐MnO@C for rechargeable AZIBs is reported. Analytical techniques confirm the porous and crystalline structure of ZnO‐MnO@C and the in situ growth of Mn deficient ZnMn2O4@C. The Zn/Mn‐d‐ZMO@C cell displays a promising capacity of 194 mAh g−1 at a current density of 100 mA g−1 with 84% of capacity retained after 2000 cycles (at 3000 mA g−1 rate). The improved performance of this cathode originates from in situ orientation, porosity, and carbon coating. Additionally, first‐principles calculations confirm the high electronic conductivity of Mn‐d‐ZMO@C cathode. Importantly, a good capacity retention (86%) is obtained with a year‐old cell (after 150 cycles) at 100 mA g−1 current density. This study, therefore, indicates that the in situ grown Mn‐d‐ZMO@C nanoarchitecture cathode is a promising material to prepare a durable AZIB., A novel battery consisting of zinc anode and Mn deficient ZnMn2O4@C cathode has been developed by immersing ZnO‐MnO@C electrode in 2 m ZnSO4 + 0.2 m MnSO4. The in situ formation of a reversible ZnMn2‐ xO4@C with Zn4(OH)6(SO4).xH2O surface layer exhibits extraordinary cycle performance.

We demonstrate the broadband visible luminescence from bulk crystalline silicon and silicon nanoparticles sized 100- 30 nm under near-infrared excitation. We show that the luminescence spectrum has two distinct peaks. The first being centered at 550 nm while the second appears close to the wavelength of the second harmonic of the excitation light. The appearance of the second peak is a signature of the highly athermal electron distribution never observed previously. The luminescence intensity and spectral shape strongly depend on the doping type and concentration. Despite being nonresonant, silicon nanoparticles enhance luminescence intensity when placed atop the silicon wafer. The observed phenomenon can be used for wafer inspection and defect detection, as well as for the creation of novel nanosources of light.

Detection of a single nanoparticle on a bare silicon wafer has been a challenge in the semiconductor industry for decades. Currently, the most successful and widely used technique is dark-field microscopy. However, it is not capable of detecting single sub-10 nm particles owing to a low signal-to-noise ratio (SNR). As a new approach, we suggest using the second harmonic generation (SHG) to detect a single nanoparticle. The second harmonic generation in centrosymmetric materials, like silicon, is forbidden except for a thin and additionally increase local field factors, allowing for their persistent detection. Choosing the proper surface and increasing SNR. We demonstrate the feasibility of the nonlinear dark-field microscopy concept by detecting an isolated 80-nm silicon nanoparticle on the silicon wafer.

Lithium-ion batteries (LIBs) are widely used in various electronic devices and have garnered a huge amount of attention. In addition, evaluation of the intrinsic properties of LIB cathode materials is of considerable interest for practical applications. Therefore, through first-principles calculations based on the density functional theory, we investigated the structural, electronic, electrochemical, and kinetic properties of mixed transition metals, that is, Ni-substituted LiMnPO

Organic thin films with smooth surfaces are mandated for high-performance organic electronic devices. Abrupt nucleation and aggregation during film formation are two main factors that forbid smooth surfaces. Here, we report a simple fast cooling (FC) adapted physical vapor deposition (FCPVD) method to produce ultrasmooth organic thin films through effectively suppressing the aggregation of adsorbed molecules. We have found that thermal energy control is essential for the spread of molecules on a substrate by diffusion and it prohibits the unwanted nucleation of adsorbed molecules. FCPVD is employed for cooling the horizontal tube-type organic vapor deposition setup to effectively remove thermal energy applied to adsorbed molecules on a substrate. The organic thin films prepared using the FCPVD method have remarkably ultrasmooth surfaces with less than 0.4 nm root mean square (RMS) roughness on various substrates, even in a low vacuum, which is highly comparable to the ones prepared using conventional high-vacuum deposition methods. Our results provide a deeper understanding of the role of thermal energy employed to substrates during organic film growth using the PVD process and pave the way for cost-effective and high-performance organic devices.

We rediscover the null ellipsometry principle for an outstanding image-contrast enhancement method for darkfield imaging. Simply by adding polarizers, compensators, and a photodiode sensor to a conventional darkfield imaging system and applying the null principle, Si nano-cylinder structures as small as D20 nm (H20 nm) on non-patterned wafer, and gap defects as small as 14.6 nm and bridge defects as small as 21.9 nm on 40 nm line and 40 nm space patterns (H40 nm), which are invisible in conventional darkfield imaging, can be distinguished from scattered noise. To the best of our knowledge, no method has been successful for identifying such small non-metal (silicon) nanoscale objects with such low magnification (×20) optics.

Fe2O3 nano-particles and nano-rods were synthesized by hydrothermal synthesis method under different reaction conditions and then applied as anode materials for Lithium ion batteries. Microstructural analysis confirmed these two shapes and structures for Fe2O3 samples. It was noticed that the electrochemical performance of Fe2O3 is highly influenced by its particle morphology. Unexpectedly, Fe2O3 nano-particles exhibit excellent electrochemical performances as compared to nano-rods morphology, which may be due to the least micro strain, high stability of nano-particles structure, small agglomerations, etc. It is believed that the nano-particles structure provides extra reaction sites to accommodate large Li-ions, shorten the Li-ion diffusion paths to improve the electronic conductivity and offers large electrolyte/electrode contact area for fast electrochemical reactions. In contrast, the nano-rods morphology could not hold its structural integrity during the lithiation/de-lithiation reactions and collapsed only after certain number of cycles giving rise to poor electrochemical performances, as confirmed by post cycling ex-situ studies. More precisely, Fe2O3 nano-particles electrode delivered the excellent reversible capacity of 1125 mAh g−1 and 1007 mAh g−1 at 1C and 4C after 100 and 80 cycles, respectively, while Fe2O3 nano-rods exhibit only 113.5 mAh g−1 at 1C and 326.7 mAh g−1 at 4C.

In the present work, one–dimensional porous NiO nano-rods as an anode material were synthesized using facile hydrothermal synthesis method to improve the electrochemical performance for LIBs application. The NiO nano-rods were typically several hundred nanometers in length, which are composed by loosely stacked nanoparticles. It is believed that the obtained architecture with mesoporous structure can ensure rapid electrons/ions transfer, penetration of the electrolyte to the electrode surfaces and buffer the volume expansion of NiO during charge/discharge processes. When evaluated as anode material, the NiO nano-rods exhibit excellent rate performance and long-life cycling performance with high reversibility. The porous NiO nano-rods exhibit a capacity of 1029.3 mA h g−1 at 1C up to 100 cycles and even retains a reversible capacity of 548.4 mA h g−1 at 4C after 80 cycles. Thus, it is believed that the current strategy can be applicable to improve the electrochemical performances of various metal oxide electrodes in rechargeable secondary battery.

We have successfully synthesized Reduced graphene oxide (rGO) sheets by modified Hummer’s method without additional reducing procedures, such as chemical and thermal treatment, by using appropriate drying temperatures under ambient atmosphere. The rGO sample dried at the optimum temperature of 250 has the most increased specific surface area and porosity as evidenced by SEM and BET analysis, leading to improved lithium-ion, sodium-ion and potassium-ion storage properties. We confirmed the use of a moderate drying temperature led to electrodes’ enhanced cyclability and good electrochemical performance at high current densities. The dimensions of the sheets ranged from nanometers to micrometres and these were entangled with each other to form aggregates. These morphological features of rGO facilitates the movement of guest ions larger than Li-ions, however there were slight instability during repeated cycling. To improve the electrochemical properties, we adopted simple chemical strategies using surfactant/solvent-assisted ultrasonication or mechanical or thermal methods. Our results will be useful for improving the full cell characteristics, and especially for preventing potential drop in sodium-ion batteries and potassium-ion batteries, which are expected to replace the lithium-ion battery system.

Research attention in aqueous rechargeable zinc-ion batteries (ARZIBs) is growing immensely because of their low-cost and eco-friendly cell components. However, its challenging to find new cathode materials towards practical application of ARZIBs. In this contribution, ground-breaking work on the potassium-pillared V2O5.nH2O (K0.5V2O5.nH2O) nanorod with exposed layer structure as high-performance cathode for ARZIB is presented. The storage mechanism of the K0.5V2O5.nH2O cathode in ARZIB is systematically elucidated using a combined of in situ synchrotron X-ray diffraction, ex situ synchrotron X-ray absorption spectroscopy, ex situ TEM analyses, and first-principle calculations. The K0.5V2O5. nH2O cathode displays a notable discharge capacity of 439 mAh g−1 at a current density of 50 mA g−1. Furthermore, it recovers 96% of the capacity after 1500 cycles at 8000 mA g−1. Impressively, the Zn/K0.5V2O5.nH2O battery offers a specific energy of 121 Wh kg−1 at a high specific power of 6480 W kg−1. The superior performance of the cathode is attributed to its unique exposed layer structure with high surface energy, high conductivity, and low migration barrier. The zinc (Zn) insertion pathway into K0.5V2O5.nH2O was studied using density function theory (DFT). This study provides an insight for designing high-performance cathode materials for ARZIBs and other electrochemical systems.

In this work, we studied about Br-doped Li4Ti5O12-xBrx (“x”= 0, 0.1, 0.3, 0.5 and 0.7) anode materials, which were synthesized by a conventional solid-state reaction using precursors of Li2CO3, TiO2 and LiBr, and we found that their electrochemical properties were related to the doping behavior Most of the Br ions are situated on the surfaces/interfaces of agglomerated particles rather than in the bulk lattice after quantitative instrumental analysis. This lead to the formation of Narrow conduction paths of electron and Li-ion on their surfaces/interfaces. The presence of these narrow surface electrical conduits increased the rate-capability of the LTOBr samples during charging/discharging process. Highly Br-doped sample (LTOBr0.7) showed a slight reduction in capacity. The LTOBr0.5 sample, by the mean time, showed the highest capacity of 125 mAh/g at 1C compared to 115 mAh/g for pure LTO. This was explained with the formation of fine precipitations (Br-containing second phase) on the surfaces of the LTO particles due to high Br addition. The formation of fine precipitations (Br-containing second phase) on the surfaces of the LTO particles due to high Br addition could be the explanation of this.

Because of the complex mechanisms mediating cancer onset, prognosis, and metastatic behavior, different therapeutic approaches targeting these mechanisms have been investigated. Recent advancements in nanocarrier-based drug and gene delivery methods have encouraged scientific groups to investigate various novel therapeutic techniques. In this study, a poly(amidoamine) (PAMAM) polymer-based gene carrier containing the cathepsin B-enzyme sensitive sequence (glycine-phenylalanine-leucine-glycine, GFLG) was evaluated to determine transfection efficiency. Following the GFLG sequence, the surface of PAMAM generation 4 (G4) was conjugated with histidine (H) and arginine (R) for improved endosomal escape and cellular uptake, respectively. The successful synthesis of G4-GLFG-H-R was confirmed by H-1-nuclear magnetic resonance spectroscopy. The polyplex composed of G4-GLFG-H-R and pDNA was simulated by the enzyme cathepsin B and induced endosomal escape of pDNA, which was confirmed by gel electrophoresis. Compared with the G4 control, enzyme-sensitive G4-GLFG-H-R showed higher transfection efficiency and lower cytotoxicity in HeLa cells. These results demonstrated that G4-GLFG-H-R may be a highly potent and efficient carrier for gene therapy applications.

The conformational relaxation of a polymer chain often slows down in various biological and engineering processes. The polymer, then, may stay in nonequilibrium states throughout the process such that one may not invoke the local thermal equilibrium (LTE) approximation, which has been usually employed to describe the kinetics of various processes. In this work, motivated by recent single-molecule experiments on DNA packaging into a viral capsid, we investigate how the nonequilibrium conformations and the LTE approximation would affect the packaging of a polymer chain into small confinement. We employ a simple but generic coarse-grained model and Langevin dynamics simulations to investigate the packaging kinetics. The polymer segments (both inside and outside the confinement) stay away from equilibrium under strong external force. We devise a simulation scheme to invoke the LTE approximation during packaging and find that the relaxation of nonequilibrium conformations plays a critical role in regulating the packaging rate.

Reduced graphene oxide (rGO) sheets were synthesized by a modified Hummer's method without additional reducing procedures, such as chemical and thermal treatment, by appropriate drying of graphite oxide under ambient atmosphere. The use of a moderate drying temperature (250°C) led to mesoporous characteristics with enhanced electrochemical activity, as confirmed by electron microscopy and N 2 adsorption studies. The dimensions of the sheets ranged from nanometres to micrometres and these sheets were entangled with each other. These morphological features of rGO tend to facilitate the movement of guest ions larger than Li + . Impressive electrochemical properties were achieved with the rGO electrodes using various charge-transfer ions, such as Li + , Na + and K + , along with high porosity. Notably, the feasibility of this system as the carbonaceous anode material for sodium battery systems is demonstrated. Furthermore, the results also suggest that the high-rate capability of the present rGO electrode can pave the way for improving the full cell characteristics, especially for preventing the potential drop in sodium-ion batteries and potassium-ion batteries, which are expected to replace the lithium-ion battery system

Zinc sulfide (ZnS(O)) thin films doped with Mn, Ni, and Co ions are synthesized by chemical bath deposition technique onto glass substrates. X-ray diffraction study reveals that the undoped and metal-doped ZnS(O) films possess a hexagonal wurtzite crystal structure. The morphological change, upon metal-ions doping, from nanorod structures to cluster (Mn doping), compact (Ni doping), and granular shapes (Co doping) is observed. X-ray photoelectron spectroscopy reveals the presence and incorporation of metal ions into ZnS(O) lattice sites and the formation of a metal–ZnS combined structure. The band gap energy of the undoped ZnS(O) film is found to be larger than 4.0 eV, while it is 3.8, 3.7, and 3.6 eV for the Mn–ZnS(O), Ni–ZnS(O), and Co–ZnS(O) films, respectively. All the undoped and metal-doped ZnS(O) samples exhibit blue luminescence, which originates from the surface defects and trap centers. Thus, the photoluminescence (PL) (blue light emission) is due to the radiative recombination from various trap levels (shallow donor levels) to the valence band. The decrease in the PL peak intensity for the doped samples indicates the reduction of surface defects suggesting the incorporation of metal ions into the host lattice of ZnS(O). Based on the PL results, the PL energy-level diagram for the undoped and metal-doped ZnS(O) samples is proposed.

An effective synthesis strategy is employed to fabricate Cu2ZnSnS4 (CZTS) thin films using radio frequency (rf) magnetron sputtering technique on soda lime glass substrates. The as-grown films are annealed at different temperatures ranging between 350 and 550 °C, and their chemical compositions and structural properties are investigated. The as-grown films have poor Cu/(Zn + Sn) ratios ranging between 0.39 and 0.44 and S/(Cu + Zn + Sn) ratios ranging between 0.97 and 1.21. The Cu/(Zn + Sn) ratio is improved by growing a thin additional Cu-capping layer on the as-grown film followed by annealing. An improved Cu/(Zn + Sn) ratio of ∼0.71 is obtained and the S/(Cu + Zn + Sn) ratio is slightly reduced to ∼0.85. The formation of a kesterite type CZTS is confirmed using X-ray diffraction and Raman spectroscopy measurements. Absorption measurements and band-gap energy determination of the CZTS films are carried out in order to confirm applicability to solar cells.

For the first time, a new carbon–carbon composite electrode material for supercapacitors is prepared by simple KOH activation of waste newspaper. The amorphous nature and surface morphology of the carbon composite are investigated by X-ray diffraction (XRD), N 2 adsorption/desorption and scanning electron microscopy. The surface area and pore diameter are 416 m 2 g −1 and 5.9 nm, respectively. Electrochemical characteristics are evaluated by cyclic voltammetry (CV) and charge–discharge tests in 6.0 M KOH at a 1 mA cm −2 current density. The CV results reveal a maximum specific capacitance of 180 F g −1 at a 2 mV s −1 scan rate and the data explore a development of new use for waste paper into a valuable energy storage material.

Diamond-like carbon (DLC) films have been fabricated by pulsed laser deposition (PLD). The effect of the laser fluence and the substrate temperature on the properties of DLC films was systematically investigated. The substrate temperatures in the range of room temperature to 600°C were varied systematically to observe the effect of substrate temperature on the property of DLC films. Also, film depositions at laser fluences from 6 to 17 J cm −2 were investigated. High-quality DLC films were obtained with the deposition parameters of substrate temperature of 300°C and laser fluence of 12 J cm −2 .

Metal-organic framework (MOF) based synthesis of battery electrodes has presently become a hot topic of significant research interest. Considering the complications to prepare Co3V2O8 due to the criticality of its stoichiometric composition, we report here by a simple MOF formation by solvothermal technique followed by air annealing to synthesize Co3V2O8 for use as potential anodes for lithium battery applications. Structrual investigations by X-ray diffraction, X-ray photoelectron spectroscopy, high resolution electron microscopy, and surface area studies revealed that the phase pure Co3V2O8 nanoparticles are inter connected to form a sponge-like morphology with porous properties. Electrochemical measurements exposed the excellent lithium storage (~ 1000 mAhg-1 at 200 mAg-1) and retention properties (500 mAhg-1 at 1000 mAg-1 after 700 cycles) of the prepared Co3V2O8 electrode. A notable rate performance of 430 mAhg-1 at 3200 mAg-1 was also observed and ex-situ analysis confirmed the morphological and structural stability of this material after long cycles performance. These results validate that the unique nanostructured morphology arising from the use of the ordered array of MOF networks is favorable for improving the cyclability and rate capability in battery electrodes. The synthetic strategy presented herein may provide solutions to develop phase pure mixed metal oxides for high performance electrodes for useful energy storage applications. Figure 1