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Metal–Organic Polymers (MOPs) have attracted growing attention for lithium-ion battery (LIB) applications due to their merits in orderly ionic transportation and robust structure stability in electrochemical reactions. However, they suffer from poor electronic conductivity. In this work, we apply first-principles density functional theory to explore the potential of three one-dimensional (1D) electrically conductive C6H2S4TM (TM = Fe, Co, and Ni) MOPs with the π–d conjugated coordination as anode materials for Li+ ions storage. Our theoretical results reveal that these 1D MOPs possess a superior theoretical capacity of over 748 mA h g−1. In particular, the 1D C6H2S4Ni MOP shows an exceptional theoretical specific capacity of 1110 mA h g−1 based on the three-electron transferring reaction, which significantly outperforms the traditional graphite-based anode material in LIBs. Moreover, the resonant charge transfer between Ni metal and ligand within the 1D C6H2S4Ni MOP reduces the diffusion energy barrier of the Li atoms when they migrate on the surface of the MOP. The ultrahigh theoretical specific capacity of the C6H2S4Ni MOP predicts that it can be a promising anode material for LIBs. [ABSTRACT FROM AUTHOR]

Aqueous zinc‐based energy storage devices have competitive advantages such as high power density, good safety, and wide source. However, because of the direct touch among zinc anode and aqueous electrolyte, dendrite growth and electrode side reactions are easy to occur in the plating and striping process, which seriously hinders the further development of aqueous zinc‐based energy storage devices. Therefore, it is urgent to solve the above problems to expand the existing energy storage devices. In this work, by adding an imidazo[1,2‐b]pyridazine (IP) electrolyte additive, the dendrites' growth and corrosion on the zinc anode surface could be effectively inhibited by the shielding‐anchoring double effects, which are verified by the comprehensive in situ and ex situ characterization techniques as well as the theoretical calculation support. Accordingly, the IP‐based electrolyte encourages extremely high stable zinc anode (cycling 2200 h at 1 mA cm−2) with high average Coulombic efficiency (98.72%). Moreover, the IP‐based Zn‐V2O5 full battery also exhibits excellent reversible capacity, reaching 160.8 mAh g−1 after 400 cycles at 2 A g−1. Through a straightforward alteration to the Zn anode surface, this study considerably enhances the use of highly stable and secure aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]

Zinc ion batteries (ZIBs) have recently attracted tremendous interest for being low‐cost, environmentally benign, and high energy density. However, the large‐scale practical application of ZIBs is hampered by well‐known undesirable dendrite growth and serious side reactions of the Zn anode during the long‐term cycling process. Herein, a multifunctional water‐glass artificial protection layer with enormous Si─O functional groups is constructed on Zn anode through a simple spin‐coating method. The theoretical and experimental investigation suggests that the as‐constructed interface with rich Si─O hydrophilic functional groups on Zn anode could facilitate the even distribution of electric field distribution and homogeneous wettability, navigate uniform zinc deposition/stripping along the (002) plane, and subsequently lead to well‐suppressed dendrite growth and effective prohibition of oxygen‐involved corrosion. Consequently, the water glass‐modified anode achieves highly reversible Zn plating/stripping over 1500 h at a high current density of 10 mA cm−2 in symmetrical cells, and a high capacity retention ratio of 79.4% at the current density of 5 A g−1 in full cells paired with V2O5 cathode. This proposed water glass coating layer design is cheap, up‐scalable, and facile, which could substantially accelerate the rapid commercialization of zinc anodes and unleash the full potential of renewable ZIBs for next‐generation large‐scale energy storage. [ABSTRACT FROM AUTHOR]

Lithium–sulfur batteries (LSBs) currently suffer from severe polysulfide shuttling, slow redox kinetics at the sulfur cathode, and irreversible dendrite growth at the lithium anode. To address these issues, a dual interfacial engineering strategy on both the cathode and anode is proposed. For the cathode, iminated polyaniline (iPANI) is used to achieve energetic engineering to induce mid‐energy level to the adsorption of polysulfides, and catalyze the redox conversion of sulfur species, and realize morphological engineering via self‐assembly of iPANI onto a scaffold integrated by reduced graphene oxide (rGO) and carbon nanotubes (CNTs), namely iPANI@rGO‐CNTs. For the anode, the highly conductive and lithiophilic nature and porous nanostructure of the iPANI@rGO‐CNTs composite facilitates the uniform deposition of lithium‐ions, significantly preventing the growth of lithium dendrites. Density functional theory calculations suggest that the iminated functional group at the excited state in iPANI can significantly suppress the shuttling effect, catalyze the conversion of sulfur species, and enhance the conversion of the sulfur species on the sulfur cathode. With the synergic effects of the iPANI@rGO‐CNTs nanoreactors, the as‐prepared LSBs deliver an excellent rate capability and outstanding cycling life. This large‐scale production and application of the iPANI@rGO‐CNTs nanocomposite may lead to the eventual commercialization of LSBs. [ABSTRACT FROM AUTHOR]

Highlights: Cyclohexanedodecol (CHD) could facilitate the Zn dendrite-free plating/stripping at a nanoscale. The CHD molecules could effectively modify the hydrated Zn(H2O)62+ structure in aqueous Zn ion batteries. The addition of CHD could establish robust protection layers on the Zn electrode surface. The CHD-modified electrolytes exhibit long-term cycling stability. Aqueous zinc-ion batteries (AZIBs) can be one of the most promising electrochemical energy storage devices for being non-flammable, low-cost, and sustainable. However, the challenges of AZIBs, including dendrite growth, hydrogen evolution, corrosion, and passivation of zinc anode during charging and discharging processes, must be overcome to achieve high cycling performance and stability in practical applications. In this work, we utilize a dual-functional organic additive cyclohexanedodecol (CHD) to firstly establish [Zn(H2O)5(CHD)]2+ complex ion in an aqueous Zn electrolyte and secondly build a robust protection layer on the Zn surface to overcome these dilemmas. Systematic experiments and theoretical calculations are carried out to interpret the working mechanism of CHD. At a very low concentration of 0.1 mg mL−1 CHD, long-term reversible Zn plating/stripping could be achieved up to 2200 h at 2 mA cm−2, 1000 h at 5 mA cm−2, and 650 h at 10 mA cm−2 at the fixed capacity of 1 mAh cm−2. When matched with V2O5 cathode, the resultant AZIBs full cell with the CHD-modified electrolyte presents a high capacity of 175 mAh g−1 with the capacity retention of 92% after 2000 cycles under 2 A g−1. Such a performance could enable the commercialization of AZIBs for applications in grid energy storage and industrial energy storage. [ABSTRACT FROM AUTHOR]

Improving the stability of lithium (Li) anodes is critical for the safety and reliability of Li metal batteries. Developing a 3D conductive Li host is suggested as one of the most promising strategies in this context, especially for suppressing the pulverization of the electrode. However, the material consistency and volume expansion of the electrodes (<15%) represent significant challenges for their applications in commercial pouch cells. In this work, dual‐gradient architecture, combining rigidity and flexibility through the synergistic effect of silver wires and carbon nanotubes, is fabricated by a facile suction filtration method. This unique network shows a volume expansion of only 5.4%, outperforming all previously reported composite Li anodes. In addition, the online digital holography clearly monitors the preferential deposition of metallic Li at the lithiophilic layer. Consequently, the present gradient host effectively prevents the deposition of metallic Li at the electrode/separator interface, resulting in excellent cycling stability in both symmetric and full cells. [ABSTRACT FROM AUTHOR]

Lithium metal is considered as an ideal substitute to low‐capacity carbon anodes for rechargeable lithium‐ion batteries (LIBs) given its ultra‐high theoretical specific capacity of 3860 mAh g−1 and the lowest electrochemical potential. However, safety issues stem from the uncontrollable formation and growth of lithium dendrites, which severely plague the practical application of the Li anode. Here, a multi‐functional protection layer, prepared by a one‐step spin‐coating of CuCl2N‐Methyl‐2‐Pyrrolidone (NMP) solution on a lithium metal surface is constructed. The as‐prepared protective layer has a variable porous morphology that consists of a conductive lithium‐copper alloy and electrochemically active CuCl, which proactively facilitates the homogeneous diffusion of Li‐ions, the elimination of random dendrite nuclei, and even distribution of charge at the Li anode surface, and subsequently the uniform deposition of Li+ ions. Under such a dynamic protection mechanism, the proposed CuCl2 modified Li electrode can stably cycle more than 1500 h at a current density of 1 mA cm−2 paired with lithium foil. Moreover, the assembled full battery achieves capacity retention of 85.6% even after 2000 cycles at a high rate of 5 C with a LiFePO4 cathode. This as‐proposed dynamic protection mechanism via the incorporation of the electrochemically active component could provide new guidance in the preparation of the safe and high‐performance lithium metal anodes. [ABSTRACT FROM AUTHOR]

Further commercial application of low‐cost NiO‐based anodes is hindered by their large volume expansion after full lithiation and relatively poor theoretical capacity. To improve these issues, transition metal (Fe, Co, or Mn)‐modified triple‐shelled NiO microspheres (TS‐NiO) are successfully synthesized by using a hard template double‐adsorption method. Among them, the Fe‐modified TS‐NiO (TS‐NFO) exhibits an extraordinary lithium storage ability with high reversible capacity and outstanding cycling stability (2061.1 mAh g−1 after 800 cycles at 0.5 A g−1), which is the highest performing nickel oxide‐based anode reported to date. The outstanding electrochemical performance of TS‐NFO can be ascribed to its unique triple‐shelled structure. The inner core of TS‐NFO is composed of NiO and is encapsulated by two outer shells which are composed of a mixture of α‐Fe2O3 and NiFe2O4, resulting in a unique hollow triple‐shelled structure (NiO@α‐Fe2O3/NiFe2O4). The void space between the triple shells leaves room for their volume changes during lithiation/delithiation, which improves the cycling stability. In addition, the introduced α‐Fe2O3/NiFe2O4 outer shells increase the energy density and reversible capacity due to a synergistically interactive effect. [ABSTRACT FROM AUTHOR]

The poor cycling stability resulting from the large volume expansion caused by lithiation is a critical issue for Si‐based anodes. Herein, we report for the first time of a new yolk–shell structured high tap density composite made of a carbon‐coated rigid SiO2 outer shell to confine multiple Si NPs (yolks) and carbon nanotubes (CNTs) with embedded Fe2O3 nanoparticles (NPs). The high tap density achieved and superior conductivity can be attributed to the efficiently utilised inner void containing multiple Si yolks, Fe2O3 NPs, and CNTs Li+ storage materials, and the bridged spaces between the inner Si yolks and outer shell through a conductive CNTs "highway". Half cells can achieve a high area capacity of 3.6 mAh cm−2 and 95 % reversible capacity retention after 450 cycles. The full cell constructed using a Li‐rich Li2V2O5 cathode can achieve a high reversible capacity of 260 mAh g−1 after 300 cycles. [ABSTRACT FROM AUTHOR]

Silicon has demonstrated great potential as anode materials for next-generation high-energy density rechargeable lithium ion batteries. However, its poor mechanical integrity needs to be improved to achieve the required cycling stability. Nano-structured silicon has been used to prevent the mechanical failure caused by large volume expansion of silicon. Unfortunately, pristine silicon nanostructures still suffer from quick capacity decay due to several reasons, such as formation of solid electrolyte interphase, poor electrical contact and agglomeration of nanostructures. Recently, increasing attention has been paid to exploring the possibilities of hybridization with carbonaceous nanostructures to solve these problems. In this review, the recent advances in the design of carbon-silicon nanohybrid anodes and existing challenges for the development of high-performance lithium battery anodes are briefly discussed. [ABSTRACT FROM PUBLISHER]

Anatase TiO2microspheres with exposed mirror-like plane {001} facets were successfully synthesized viaa facile hydrothermal process. The photoanode composed of TiO2microsphere top layer shows an improved DSSCs efficiency owing to the superior light scattering effect of microspheres and excellent light reflecting ability of the mirror-like plane {001} facets. [ABSTRACT FROM AUTHOR]

Aluminum is one of the promising alternative anode materials due to its high specific capacity. However, some critical problems seriously limit its practical applications, such as the low coulombic efficiency and poor cycle performance resulting from the huge volume change during cycling. Herein, a novel poly(furfuryl alcohol)/carbon black binder composite is coated on the surface of aluminum foil as a robust and conductive protective layer to maintain the integrity of the hybrid aluminum anode. The results show that 150 cycles under the preset cutoff capacity loading of 400 mA h g−1 are obtained and exhibit obvious advantages over a bare aluminum anode, which will crack after just 25 cycles. For full‐cell testing paired with a LiFePO4 cathode, the cell using the hybrid aluminum anode has a better capacity retention against the unprotected aluminum anode. [ABSTRACT FROM AUTHOR]

In article number 1802645, Zhan Lin, Jun Lu and co‐workers propose a universal strategy for interweaving hard and soft polymers to construct 3D network binders to enable high areal capacities with excellent cyclability in lithium‐ion batteries. Elastic modules accommodate the volume variation of Si particles while stiff modules offer mechanically strong electrode frameworks. This strategy can provide a new principle in designing robust binder for high‐energy‐density lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) are emerging as an inexpensive and more sustainable alternative to lithium-ion batteries in the energy storage market. To advance their commercialization, one major scientific undertaking is to develop low-cost, reliable anode materials from abundant resources, like the success of graphite in the lithium-ion batteries. However, graphite is chemically inactive in storing sodium ions and, to render it viable in sodium-ion batteries, additional modification of graphite is required. Herein, we demonstrate a green and facile method to prepare cost-effective and stable graphitic SIB anodes. The modification process started with the electrochemical oxidation of expanded graphite to widen the interlayer and functionalize graphite layers, followed by a fast (20 min) thermal treatment at 150 °C to achieve controlled deoxygenation. The thermally processed electrochemical graphite oxide could provide a high reversible capacity of 268 mAh g−1 at 100 mA g−1 and 163 mAh g−1 at 500 mA g−1 as well as low fading in capacity (in average 0.0198% loss per cycle) over 2000 cycles. The electrochemical route eliminates the need for the harsh chemical oxidation of graphite, offering a promising approach for industrial production of low-cost anodes for sodium-ion batteries. [Display omitted] [ABSTRACT FROM AUTHOR]

Photocatalytic (PC) and photoelectrocatalytic (PEC) degradation of small biological compounds such as nucleotide bases were carried out because of the nucleotide bases are the building blocks of large biomolecules, nucleic acids. These small biological compounds, four different nucleotide bases, can be photocatalytically and photoelectrocatalytically degradable, and the degradation efficiencies of PEC method were found to be higher than those of PC method for all compounds investigated. Also, we tried to propose the photocatalytical and photoelectrocatalytic degradation mechanisms of nucleotide bases, but the performance was unsuccessful. However, organic nitrogen in the original compounds was found to be oxidized to either NH 3 /NH 4 + or NO 3 − or both, depending on the chemical structures of the nucleotide bases and the degradation methods used. Based on both the experimental results and the theoretically calculated frontier electron densities (FED) values of 2FED HOMO 2 and FED HOMO 2 + FED LUMO 2 , the conclusion can be demonstrated as the reaction mechanisms/pathways of PEC processes differed remarkably from that of PC processes. [ABSTRACT FROM AUTHOR]

Abstract: Graphene nanosheets are synthesized by a novel facile method involving freeze-drying technology and thermal reduction. The microstructure and morphologies are characterized by X-ray diffraction, Brunauer–Emmett–Teller measurements, Fourier transform infrared spectroscopy, and high resolution transmission electron microscope. The results indicate that graphene nanosheets with high specific surface area (358.3 m2 g−1) and increased interlayer distance (0.385 nm) are successfully obtained through the freeze-drying process. The electrochemical performances are evaluated by using coin-type cells versus lithium. A high initial reversible capacity of 1132.9 mAh g−1 is obtained at a current density of 100 mA g−1. More importantly, even after 300 cycles at a high current density of 1000 mA g−1, a stable specific capacity of 556.9 mAh g−1 can be achieved, suggesting the graphene nanosheets exhibit superior cycle stability. The fascinating electrochemical performance could be ascribed to the high specific surface area and the increased layer distance between the graphene nanosheets. [Copyright &y& Elsevier]

Abstract: TiO2/nitrogen-doped graphene nanocomposite was synthesized by a facile gas/liquid interface reaction. The structure and morphology of the sample were analyzed by X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy. The results indicate that nitrogen atoms were successfully doped into graphene sheets. The TiO2 nanoparticles (8–13nm in size) were homogenously anchored on the nitrogen-doped graphene sheets through gas/liquid interface reaction. The as-prepared TiO2/nitrogen-doped graphene nanocomposite shows a better electrochemical performance than the TiO2/graphene nanocomposite and the bare TiO2 nanoparticles. TiO2/nitrogen-doped graphene nanocomposite exhibits excellent cycling stability and shows high capacity of 136mAhg−1 (at a current density of 1000mAg−1) after 80cycles. More importantly, a high reversible capacity of 109mAhg−1 can still be obtained even at a super high current density of 5000mAg−1. The superior electrochemical performance is attributed to the good electronic conductivity introduced by the nitrogen-doped graphene sheets and the positive synergistic effect between nitrogen-doped graphene sheets and TiO2 nanoparticles. [Copyright &y& Elsevier]