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Two-dimensional (2D) materials with honeycomb, kagome or star lattice have been intensively studied because electrons in such lattices could give rise to exotic quantum effects. In order to improve structural diversity of 2D materials to achieve unique properties, here we propose a new quasi-2D honeycomb-star-honeycomb (HSH) lattice based on first-principles calculations. A carbon allotrope named HSH-C10 is designed with the HSH lattice, and its mechanical properties have been intensively investigated through total energy, phonon dispersion, ab initio molecular dynamic simulations, as well as elastic constants calculations. Besides the classical covalent bonds, there is an interesting charge-shift bond in this material from the chemical bonding analysis. Additionally, through the analysis of electronic structure, HSH-C10 is predicted to be a semiconductor with a direct band gap of 2.89 eV, which could combine the desirable characteristics of honeycomb and star lattice. Importantly, by modulating coupling strength, a flat band near the Fermi level can be obtained in compounds HSH-C6Si4 and HSH-C6Ge4, which have potential applications in superconductivity. Insight into such mixed lattice would inspire new materials with properties we have yet to imagine.

The electrocatalytic oxygen evolution reaction (OER) is necessary and challenging for converting renewable electricity into clean fuels, because of its complex proton coupled multielectron transfer process. Herein, we investigated the crystal plane effects of NiO on the electrocatalytic OER activity through combining experimental studies and theoretical calculations. The experimental results reveal that NiO nanobelts with exposed {110} crystal planes show much higher OER activity than NiO nanoplates with exposed {111} planes. The efficient OER activity of the {110} crystal planes comes from their intrinsically high catalytic ability and fast charge transfer kinetics. Density functional theory (DFT) shows that the {110} crystal planes possess a lower theoretical overpotential value for the OER, leading to a high electrocatalytic performance. This research broadens our vision to design efficient OER electrocatalysts by the selective exposure of specific crystal planes.

Unique 2D lamellar VS2/MoS2 heterojunctions boost reaction kinetics of Na+ and improve long cycle life for sodium storage.

Ammonia (NH3) is one of the most important building blocks of the chemical industry and a promising sustainable energy carrier. Conventional production of NH3 via the Haber-Bosch process requires high temperature and high pressure, which is energy demanding and suffers safety issues. Photocatalytic nitrogen reduction reaction (NRR) is a green and sustainable route for NH3 production, and has been expected to be an alternative for NH3 production under mild conditions. However, solar-driven N2 activated has appeared as the bottleneck for photocatalytic NRR. In this work, we propose that single Ru atom supported by BeO monolayer is a promising photocatalytic single atom catalyst (SAC) for efficient N2 activation with visible illumination. The high efficiency originates from the enhanced absorption in the visible range, as well as the back-donation mechanism when N2 were adsorbed on the SAC. Our results show that N2 can be efficiently activated by the Ru/BeO SAC and be reduced to NH3 with extremely low limiting potential of -0.41 V. The NRR process also exhibits dominate selectivity respect to hydrogen evolution.

The thermal-driven current through the device is dominated by the spin-down electrons within a wide temperature range.

Partial Cr substitution for V in the V4C3Tx MXene promotes the capacitance, discharging potential, and cycle stability of in-plane ZMSCs. The device exhibits a high areal energy density of 51.12 μW h cm−2 and flexibility index of 100.

The capacity of the N,S co-doped graphene system for Na is improved.

CO2 capture is considered as one of the most ideal strategies for solving the environmental issues and against global warming. Recently, experimental evidence has suggested that aluminum double bond (dialumene) species can capture CO2 and further convert it into value-added products. However, the catalytic application of these species is still in its infancy. Both the dynamics mechanism of CO2 fixation and the detailed structures of catalytic intermediates are not well understood. In this work, we investigate the structure dependent resonance Raman (RR) signals for different reaction intermediates. Ab-initio simulations of spontaneous resonance Raman (spRR) and time-domain stimulated resonance Raman (stRR) give spectral signatures correlated to the existence of different intermediates during the CO2-dialumene binding process. The unique Raman vibronic features contain rich structural information with high temporal resolution, enabling to monitor the transient catalytic intermediates under reaction conditions. Our work shows that RR can be used to monitor intermediates during the dialumene based CO2 capture reaction. The spectral features not only provide insight into the structural information of intermediate species, but also allow a deeper understanding of the dynamical details of this kind of catalytic process.

Photocatalytic water splitting utilizing solar energy is considered as one of the most ideal strategies for solving the energy and environmental issues. Recently, two-dimensional (2D) materials with an intrinsic dipole show great chance to achieve excellent photocatalytic performance. In this work, blue-phase monolayer carbon monochalcogenides (CX, X = S, Se) are constructed and systematically studied as photocatalysts for water splitting by performing first-principles calculations based on density functional theory. After confirming the great dynamical, thermal, and mechanical stability of CX monolayers, we observe that they possess moderate band gaps (2.41 eV for CS and 2.46 eV for CSe) and high carrier mobility (3.23 × 104 cm2 V−1 s−1 for CS and 4.27 × 103 cm2 V−1 s−1 for CSe), comparable to those of many recently reported 2D photocatalysts. Moreover, these two monolayer materials are found to have large intrinsic dipole (0.43 D for CS and 0.51 D for CSe), thus the build-in internal electric field can be self-introduced, which can effectively drive the separation of photongenerated carriers. More importantly, the well-aligned band edge as well as rather pronounced optical absorption in the visible-light and ultraviolet regions further ensure that our proposed CX monolayers can be used as high efficient photocatalysts for water splitting. Additionally, the effects of external strain on the electronic, optical and photocatalytic properties of CX monolayers are also evaluated. These theoretical predictions will stimulate further work to open up the energy-related applications of CX monolayers.

Exploring electrode materials with a high volumetric energy density and high rate capability remains of a great challenge for nanosized-Li4Ti5O12 (LTO) batteries. Here, hierarchical porous Ti3+-C-N-Br co-doped LTO (LTOCPB-CC) is synthesized using carboxyl-grafted nanocarbon (CC) and cetylpyridinium bromide (CPB) as combined structure-directing agents. Ti4+-O-CPB/Li+-CC is designed as a new molecular chelate, in which CPB and CC promote the uniform mixing of Li+ and Ti4+ and control the morphology of TiO2 and the final product. The defects (oxygen vacancies and ion dopants) formed during the annealing process increase the electron/hole concentration and reduce the band gap, both of which enhance the n-type electron modification of LTO. As-prepared LTOCPB-CC has a large specific surface area and high tap density, as well as a high electronic conductivity (2.84 × 10−4 S cm−1) and ionic conductivity (3.82 × 10−12 cm2 s−1), which are responsible for its excellent rate capability (157.7 mA h g−1 at 20 C) and stable long-term cycling performance (0.008% fade per cycle after 1000 cycles at 20 C).

With increasing demand for renewable energy, graphene-like BC3 monolayer as high performance electrode materials for lithium and sodium batteries are drawing more attention recently. However, its structural stability, potassium storage properties and strain effect on adsorption properties of alkali metal ions have not been reported yet. In this work, phonon spectra, AIMD simulations and elastic constants of graphene-like BC3 monolayer are investigated. Our results show that graphene-like BC3 monolayer possesses excellent structural stability and the maximum theoretical potassium storage capacity can reach up to 1653 mA h/g with the corresponding open circuit voltages 0.66 V. Due to potassium atom can be effectively adsorbed at the most energetically favorable h-CC site with obvious charge transfer, making adsorbed graphene-like BC3 monolayer change from semiconductor to metal which is really good for electrode utilization. Moreover, the migrations potassium atom on the graphene-like BC3 monolayer is rather fast with the diffusion barriers as low as 0.12 eV, comparing lithium atom with a relatively large diffusion barrier of 0.46 eV. Additionally, the tensile strains applied on the graphene-like BC3 monolayer have marginal effect on the adsorption and diffusion performances of lithium, sodium and potassium atoms.

In this work, we comprehensively study the electronic and photocatalytic properties of single-layer and multilayer bismuth oxyhalides BiOX (X=Cl, Br, and I) sheets by means of extensive density functional theory, which have been successfully synthesized in the previous experimental studies. Our computational simulations show that single-layer BiOX sheets possess indirect band gap, suitable band edge alignments, and pronounced optical properties, suggesting that they can be utilized as photocatalysts for splitting H2O into H2 and O2 from theoretical aspects. In the case of multilayer BiOX sheets, some primary physical properties determined the photocatalytic performance are rather robust, almost independent of the layer number. According to these calculated results, we are optimistic that BiOX sheets, especially for single-layer BiOI, have great chances to be used for photocatalytic water splitting.

A facile citric acid assisted sol-gel combustion method was performed to synthesize cobalt chromite (CoCr2O4) ceramic pigment. The effect of the annealing temperature on structure, morphologies, and optical properties of the prepared CoCr2O4 pigments were systematically studied by thermogravimetry, differential thermal analysis, X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). The results show that CoCr2O4 spinel crystal was achieved after heat treatment of the as-burnt powder at a relatively low temperature (400 °C) and the average crystallite size of the CoCr2O4 pigment increased with the annealing temperature. Furthermore, on the CIE parameters of CoCr2O4 pigment, a* and b* values became much more negative with the annealing temperature due to much more Co2+ ions located in tetrahedral sites and much more Cr3+ ions located in octahedral sites. Finally, the measured solar absorptance indicates that this ceramic pigment is expected to fabricate the color paint coating for solar absorber application.

The interlayer modification and the intercalation pseudocapacitance have been combined in vanadium oxide electrode for aqueous zinc-ion batteries. Intercalation pseudocapacitive hydrated vanadium oxide Mn1.4 V10 O24 ·12H2 O with defective crystal structure, interlayer water, and large interlayer distance has been prepared by a spontaneous chemical synthesis method. The inserted Mn2+ forms coordination bonds with the oxygen of the host material and strengthens the interaction between the layers, preventing damage to the structure. Combined with the experimental data and DFT calculation, it is found that Mn2+ refines the structure stability, adjusts the electronic structure, and improves the conductivity of hydrated vanadium oxide. Also, Mn2+ changes the migration path of Zn2+ , reduces the migration barrier, and improves the rate performance. Therefore, Mn2+ -inserted hydrated vanadium oxide electrode delivers a high specific capacity of 456 mAh g-1 at 0.2 A g-1 , 173 mAh g-1 at 40 A g-1 , and a capacity retention of 80% over 5000 cycles at 10 A g-1 . Furthermore, based on the calculated zinc ion mobility coefficient and Zn(H2 O)n2+ diffusion energy barrier, the possible migration behavior of Zn(H2 O)n2+ in vanadium oxide electrode has also been speculated, which will provide a new reference for understanding the migration behavior of hydrated zinc-ion.

Expanding the electrochemical stability window (ESW) of aqueous electrolytes is receiving great interest because it directly determines the energy density of electrochemical energy storage devices. Super-concentrated aqueous electrolytes (i.e. “water in salt”, WIS) with extremely high salt-to-water molar ratios enable substantially reduced water activity, thereby widening ESW. However, such aqueous electrolytes give rise to sluggish ionic transfer, leading to poor rate performance of devices. Here we report a water/organic hybrid electrolyte based on a low-cost sodium perchlorate (NaClO4) salt. The hybrid electrolyte with a salt-to-water-to-acetonitrile molar ratio of 1/1.5/2.4 shows a wide ESW, and exhibits high ionic conductivity, excellent wettability, moisture-tolerant and flame-retardant properties. Such advantages enable a safe carbon-based supercapacitor to operate at 2.5 V with high specific capacitance, and deliver a good stability over 15000 cycles.

Nanosized Li4Ti5O12 with both a Li2TiO3 coating and C-N-Br co-doping (CLLTO) was successfully synthesized via a facile reverse microemulsion method in one step using hexadecyl trimethyl ammonium bromide as a surface control agent and as a carbon, nitrogen, and bromine source. A uniform Li2TiO3 layer was formed on the surface and strongly adhered to the host material Li4Ti5O12 (LTO), which played an important role in improving the cyclic stability of CLLTO. The thin and stable Li2TiO3 layer has the same cubic structure as LTO, which provides many three-dimensional channels for ion transport. C, N, and Br co-doping in CLLTO promoted the transition of Ti4+ to Ti3+ in Li4Ti5O12, which could improve the capacity and facilitate the Li+ ion and electron transfer at the interface. The conductive behavior induced by co-doping was estimated by UV-vis diffuse reflectance spectra and further supported by theoretical calculations. The electrical conductivity of both p-type and n-type LTO can be well improved by co-doping C, N, and Br. This improvement may be due to the band gap reduction and the increased n-type electronic modification of the entire LTO. Owing to the synergistic effect of coating, co-doping, and nanosizing at one time, the CLLTO exhibits a high discharge capacity of 177.3-153.9 mA h g-1 at the working rate of 0.1C-20C, with a capacity retention of 86%. The stable cycling of CLLTO is also obtained after 500 cycles at 20C, with a capacity retention of 95.5% (approximately 8 times higher than that of pure LTO) and almost 100% Coulombic efficiency. With high capacity, excellent rate performance, and good cycling stability, CLLTO can be applied in high-power lithium-ion batteries.

A critical problem of electric double-layer capacitors (EDLCs) is that their actual operational voltages can hardly reach the theoretical values. This condition results from the unsuitable potential ranges of electrodes. Designing methods to optimize the potential ranges of electrodes is important to entirely utilize the theoretical operational voltages, thereby maximizing the energy densities of EDLCs. Here, we report a silica-grafted ionic liquid as an electrolyte additive for a model EDLC to adjust the potential ranges of electrodes. The operational voltage of the EDLC increased from 2.8 V to a theoretical value of 3.2 V, thereby resulting in an approximately 39% increase in energy density and considerably enhanced cycling stability.

Aqueous electrolytes have shown extraordinary promise for safe electrochemical energy storage devices, but their widespread use is severely limited by the narrow electrochemical stability window (ESW). Here we demonstrate the great feasibility of using a superconcentrated sodium perchlorate aqueous solution as a low-cost “water-in-salt” electrolyte to construct a high-performance carbon-based supercapacitor (SC). The attractive features of this electrolyte including wide ESW and excellent conductivity enable the model SC to fully work at 2.3 volts with superior rate capability and outstanding cycling stability. This SC exhibits a comparable energy density, a higher power density and a much lower price compared to commercial non-aqueous SCs working at 2.7 volts, representing significant progress toward practical applications.

Solid-state lithium batteries have attracted great attention owing to their potential advantages in safety and energy density. Among various solid electrolytes, solid polymer electrolyte is promising due to its good viscoelasticity, lightweight, and low-cost processing. However, key issues of solid polymer electrolyte include poor ionic conductivity and low Li

Molybdenum disulfide (MoS2) can be an efficient electro-catalyst for the hydrogen evolution reaction (HER) as an alternative to precious metals, but significant efforts are still needed to further improve its efficiency. Among various approaches, the formation of edge aligned MoS2 on an electrically conductive support is highly promising for cost-effective H2 production. Nevertheless, catalysis is highly impeded by the poor charge transport between the electrode materials and also between the multilayers of MoS2. This research presents a strategy to improve the HER catalysis by binding layers of metallic molybdenum dioxide (MoO2) and MoS2 to form hybrid MoS2/MoO2 nanosheets (attached and cross-linked to each other). Taking advantage of the hybrid structure and the mechanical strength of the carbon cloth, a catalyst with outstanding catalytic performance in the HER is demonstrated. This work shows not only a strategy to efficiently improve the electrochemical process, but also the preparation of a highly efficient catalyst for constant and robust H2 production.

Two-dimensional (2D) Ti3C2 MXene has attracted great attention in electrochemical energy storage devices (supercapacitors and lithium-ion and sodium-ion batteries) due to its excellent electrical conductivity as well as high volumetric capacity. Nevertheless, a previous study showed that multivalent Mg2+ ions cannot reversibly insert into MXene, resulting in a negligible capacity. Here, we demonstrate a simple strategy to achieve high magnesium storage capability for Ti3C2 MXene by preintercalating a cationic surfactant, cetyltrimethylammonium bromide (CTAB). Density functional theory simulations verify that intercalated CTA+ cations reduce the diffusion barrier of Mg2+ on the MXene surface, resulting in the significant improvement of the reversible insertion/deinsertion of Mg2+ ions between MXene layers. Consequently, the MXene electrode exhibits a desirable volumetric specific capacity of 300 mAh cm–3 at 50 mA g–1 as well as outstanding rate performance. This work endows MXene material with an applicati...

The properties of the electrolyte are the dominant factors for the overall performance and safety of electrical energy storage devices. Highly concentrated “water in salt” (WIS) electrolytes are inherently non-flammable, moisture-tolerant, and exhibit wide electrochemical stability windows, making them promising electrolytes for high-performance energy storage devices. However, WIS electrolytes possess intrinsically low conductivity and high viscosity, which usually impair the high-rate performance of many energy storage devices, especially supercapacitors (SCs). Additionally, the inevitable salt precipitation at low temperature for WIS electrolytes narrows down their applicable temperature range. Here, we introduce acetonitrile as a co-solvent to a typical “water in salt” electrolyte to formulate an “acetonitrile/water in salt” (AWIS) hybrid electrolyte that provides significantly improved conductivity, reduced viscosity and an expanded applicable temperature range while maintaining the aforementioned important physicochemical properties of WIS electrolytes. Using the AWIS electrolyte for a model SC remarkably enhances the high-rate performance, accompanied by a 2.4 times capacitance increase at 10 A g−1 with respect to the original WIS electrolyte. This AWIS electrolyte also enables a stable long-term cycling capability of the model SC for over 14 000 cycles at a high operation voltage of 2.2 V.

Quantum dots (QDs)/graphene composites are interesting as promising electrode materials for high-performance supercapacitors because they can well integrate the complementary features of QDs and graphene. Herein, we demonstrate a MnFe2O4 QDs/nitrogen-doped graphene (NG) material prepared by a controllable solvothermal synthesis, in which ultra-small MnFe2O4 QDs are uniformly anchored on NG surfaces. First-principles calculations elucidate that the oxygen-containing groups of graphene oxide play a crucial role in generating such a structure, and a ferrite octahedral skeleton is firstly formed followed by Mn atom insertion. Powdery MnFe2O4 QDs/NG exhibits a high specific capacitance of 517 F g−2 within a negative potential window (−1 ∼ 0 V) in KOH electrolyte. When the lower cut off voltage is extended to −1.2 V, the specific capacitance can be increased to 905 F g−1. And the condensed MnFe2O4 QDs@NG electrode (forming a similar structure to pitaya slices) with an astonishing loading mass of 18 mg cm−2 can achieve high areal and volumetric capacitances (5.3 F cm−2 and 277.6 F cm−3). Moreover, carbon encapsulation is favorable for the improvement of rate and cycling performance, allowing a satisfactory capacitance of 150 F g−1 even at 200 A g−1 as well as a superior lifetime up to 65 000 cycles. These results make such materials competitive with supercapacitor electrodes and may speed up the development of QD-based electrodes for energy storage applications.

NiO and graphene composite electrode materials, due to their synergistic effects, are gaining increasing attention in the field of energy storage. However, the nucleation mechanism of NiO on graphene is incompletely understood. Here, highly dispersed NiO nanodots with a size of 1.48 nm anchored on reduced graphene oxide (NiO NDs@rGO) were synthesized by a solvothermal method. Density functional theory (DFT) results show that NiO NDs are more easily trapped by the defects on graphene through strong adsorption, which greatly reduces the possibility of diffusion and prevents agglomeration of NiO NDs. As a result, NiO NDs are mainly connected to defects on graphene, which explain the uniform dispersion of NiO NDs on the graphene surface. This unique structure serves to promote ion accessibility and shorten the electron transfer path from redox sites to the graphene backbone. Electrochemical evaluation shows that utilizing the composite as an electrode material for aqueous electrolytes can greatly improve the overall electrochemical performance. The combination of theory and the experimental study provides guidance for the design of new electrode materials.

Using first-principles calculations, the activation of the metal clusters (Mx = Ni6, Co6, Fe6) and clusters on graphene for ammonia decomposition was investigated. It is found that the Ni6 cluster on graphene is more active for the NH3 adsorption and dissociation, and for the most important steps of ammonia decomposition, namely the initial cleavage of the NH2 − H bond, the migration of N and the N + N recombination, they are all easier to perform on the graphene-supported Ni6 catalyst than that on the Ni6 cluster, the energy barriers are reduced from 1.29 eV, 0.92 eV, 2.25 eV to 1.11 eV, 0.41 eV, 1.47 eV, respectively. This study provides new insights into the potential applications of a cheap metal-based catalysts functionalized by graphene for the current reaction.

The doping types of graphene sheets are generally tuned by different dopants with either three or five valence electrons. As a five-valence-electrons element, however, nitrogen dopants in graphene sheets have several substitutional geometries. So far, their distinct effects on electronic properties predicted by theoretical calculations have not been well identified. Here, we demonstrate that the doping types of graphene can be tuned by N monoelement under proper growth conditions using chemical vapor deposition (CVD), characterized by combining scanning tunneling microscopy/spectroscopy, X-ray/ultraviolet photoelectron spectroscopy, Hall effect measurement, Raman spectroscopy, and density functional theory calculations. We find that a relatively low partial pressure of CH4 (mixing with NH3) can lead to the growth of dominant pyridinic N substitutions in graphene, in contrast with the growth of dominant graphitic N substitutions under a higher partial pressure of CH4. Our results unambiguously confirm that...

We studied carbon nanosheets prepared from bacterial cellulose (BC) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) oxidized-BC through carbonization at temperatures ranging from 900 to 1100 °C. Based on experimental results, we propose a comprehensive perspective of Na storage for BC based anode material. The pyrolysis TEMPO-oxidized BC delivers the highest capacity at annealing temperature of 1000 °C under different current densities, and displays excellent rate capability and cyclability. The superior electrochemical performance is attributed to the increasing interlayer distance, rich porous structure and oxygen-containing functional groups. The experimental studies reveal that the introduction of carboxyl is an effective strategy to enhance the specific capacity and cycling stability for Na-ion storage.

Nanosized Li

The mediocre capacitive performance of carbon cathode has seriously hampered the advancement of lithium ion capacitors (LICs). The guideline for high-performance capacitive carbon cathode is still lacking. In this study, the desired microstructure of carbon cathode that suitable for LiPF6-contained electrolyte is calculated by using density functional theory. Results suggest that only the pore sizes more than 2.18 nm can accommodate the solvated P F 6 - ions. Experimental results confirm that the capacitive performance of the synthesized activated polyaniline-derived carbon (APDC) can be significantly promoted as the pore size was more than 2 nm. Especially, the APDC-700-based electrode demonstrates outstanding electrochemical performance with high capacitance (247 F g-1 at 0.1 A g-1) and good rate capability (156 F g-1 at 10 A g-1), owing to the appropriate pore size and high N content in carbon matrix. The APDC-700-based LIC device can deliver an ultra-high energy density of 300.3 Wh kg-1 at 318 W kg-1, as well as good cycling stability over 10 000 cycles. This well-designed work will be conducive to deeply understand the performance improvement of capacitive carbon cathode in LiPF6 electrolyte and provides guidelines for designing advanced LIC devices.

The method of increments is applied to investigate the adsorption of a single water molecule inside and outside armchair carbon nanotubes with different curvature using density-fitting local coupled cluster with single and double excitations and perturbative triples treatment (DF-LCCSD(T)). The correlation contribution to the adsorption energy is expanded in terms of localized orbitals of both the water molecule and the nanotube. Results of this investigation show that the simultaneous correlation of groups of localized orbitals of the water molecule and of the carbon nanotube (i. e. inter-fragment two-body increments) is the major contribution to the attractive interaction. In contrast the individual correlation energy of localized orbitals of water molecule or carbon nanotube (i. e. one-body increments) is negligible. A detailed balance between the repulsive Hartree–Fock contribution and the attractive correlation contribution to the adsorption energy determines the ground-state structure of the water molecule inside the carbon nanotube. To elucidate this behavior benzene-based model systems are investigated with the same methods.

Two-dimensional (2D) monolayers are promising in electrochemical energy storages (EES), while their performance is still far below than that can be exploited. Understanding 2D monolayers, particularly thin nanocrystals (NCs) with and without surface modifications in EES would be interesting. This work demonstrates how monolayered molybdenum sulfide (Mo–S) NCs with S vacancies perform as a promising anode material to improve many aspects of lithium-ion batteries (LIBs), by utilizing their metallicity, multi-layer adsorption, minimized self-discharge and fast 2D capacitive processes. By way of examples, we demonstrate an increasing trend of the energy capacity and improved lithium diffusion kinetics associating with the S vacancy and phase change, a discharge capacity of 1409 mAh g−1 at 0.1 A g−1, and even reach the capacitive dominated (>814.7 mAh g−1) capacity at 1 A g−1. It demonstrates that the surface modified Mo–S NCs can be well used in LIBs. There may be also considerable opportunities of similar 2D materials in LIBs and beyond (e.g. supercapacitor) which can fully exploit the fast 2D capacitive process and high surface capacity.

Here, we explore the transport properties and simulate the spin-crossover (SCO) temperatures of two Fe(II) complexes by performing extensive density functional theory calculations combined with non-equilibrium Green’s function technique. We find that two Fe(II) SCO complexes with the HS state display nearly perfect spin-filtering effect and the spin-down electrons govern the transport properties. Two examined Fe(II) SCO complexes display molecular switching behavior between the LS and HS states. The spin transition temperature is predicted to be 149 and 195 K for Fe(II) SCO complex with NCSe and NCBH3 coligands, respectively, which are close to the experimental values.