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DESs based nanofluids were utilized for the first time as a medium for recycling lithium ion batteries. 100% liberation efficiency and doubled leaching efficiency compared to pristine DES were achieved under mild conditions.

Polystyrene (PS) is rich in plastic materials, but it produces a large amount of waste every year, causing a huge burden on the environment. Although PS plastic is the source of a common "white pollution" in daily life, it still has a high utilization value. At the same time, the flammability of PS material determines that it cannot be applicated in places where fire accidents occur frequently. As a result, its application has been greatly limited. In order to realize the efficient utilization of waste PS and broaden its scope of application, PS was modified by hyper-crosslinking in order to improve its fire-retardant performance. In this method, the PS solution with high purity was obtained by dissolving waste PS foam with 1,2-dichloroethane (DCE), and then the hyper-crosslinked polymer with high specific surface area was prepared by adding cross-linking agent formaldehyde dimethyl acetal (FDA) and a Lewis-acid catalyst ferric chloride (FeCl3). Further studies showed that the effects of the amount of cross-linking agent FDA, catalyst FeCl3 and PS on the reaction products were different. In addition, compared the as-prepared fire-retardant materials with PS foam from the aspects of flame retardancy and thermal insulation, it can be concluded that the fire-retardant performance of the materials prepared by this method has been significantly enhanced. And it is proved that this method is feasible towards the preparation of a large number of fire-retardant composite materials by using a scale-up experiment.

The main factors limiting water splitting producing hydrogen production are overpotential, activity and persistence of electrocatalysts. Herein, a novel NixCo1-x(OH)2 coupled with NiFe amorphous compound array growing on nickel foam substrate (expressed as NixCo1-x(OH)2/NiFe-AM) was developed by facile hydrothermal and electrodeposition methods. Significantly, NixCo1-x(OH)2/NiFe-AM with this unique structural exhibits superior activity and stability in the two half reactions of water electrolysis. In addition, when tested in an alkaline electrolyte with a current density of 10 mA cm−2, the overpotentials of HER and OER was 157 mV and 196 mV (60 mA cm−2), respectively. The stability can up to 60 h. These test results show through constructing hierarchical nano-thron architecture enhanced electrocatalytic activity to produce hydrogen and oxygen.

Fluidized bed technology is widely used in chemical industries. The introduction of pulsating energy into a traditional fluidized bed can effectively reduce the generation of bubbles and improve th...

Graphite has been widely used as the anode material in lithium-ion batteries (LIBs) due to its good conductivity, layered crystal structure, high charging–discharge potential, and other characteristics. With the rapid development of the LIB industry, the graphite industry has also developed into a mode of high production capacity. The anode graphite of spent LIBs has the characteristics of large layer spacing and ease of being intercalated and peeled due to the reduction of the interlamination force after repeated charge and discharge cycles. In this study, we present a facile freeze–thaw ultrasonic assisted circulation method to prepare two-dimensional low-layer graphite flakes (GFs) using anode graphite from spent LIBs. Characterizations of GFs were carried out by SEM, TEM, XRD and Raman spectroscopy. The results indicate that GFs prepared by graphite of spent LIBs have a better morphology than that prepared by purchased graphite. Furthermore, the GF-filled ethylene glycol (EG) nanofluids exhibit higher thermal conductivity and conductive heat transfer coefficient than base fluids, of which the maximum enhancements are 10.5% and 30%, respectively. The freeze–thaw ultrasonic assisted circulation method is not only an effective method for the reuse of anode graphite from spent LIBs, but also a reference for the synthesis of two-dimensional materials. Furthermore, GF-filled nanofluids could be a potential heat transfer working medium.

Acting as a C1 building block, formaldehyde is of great significance in organic synthesis. It is also a key feedstock in several industries, such as resins, polymers, adhesives, and paints. Multicomponent reactions (MCRs) have emerged as applicable tools in organic reactions because efficient MCRs allow the creation of several chemical bonds in one sequence without labor-consuming reaction condition optimization and work-up procedures, thus minimizing waste production, cost, and labor consumption. In this review, we mainly focus on the recent advances in the contribution of formaldehyde, which was herein used as a versatile C1 building block to produce either acyclic or heterocyclic molecules via MCRs with the potential to be more sustainable than lengthier alternatives and used as a divergent chemical thanks to its excellent reactivity, flexibility, and hydrophilicity.

Fe7S8 has emerged as an attractive anode material for lithium-ion batteries (LIBs) due to its outstanding features such as low cost, high theoretical capacity, as well as environmental benignity. However, the rapid capacity fading derived from the tremendous volume change during the charging/discharging process hinders its practical application. Nanostructure engineering and the combination with carbonaceous material are essential to address this issue. In this work, Fe7S8 nanocrystals decorated on N, S-codoped carbon nanotubes (Fe7S8-NSC) were synthesized through a facile one-step pyrolysis of Fe-containing polypyrrole (PPy) nanotubes with sulphur powders under nitrogen atmosphere. When evaluated as anode of LIBs, Fe7S8-NSC demonstrates excellent cycling stability (718.8 mAh g-1 at 100 mA g-1 after 100 cycles) and superior rate ability (290.8 mAh g-1 at 2000 mA g-1). Moreover, Fe7S8-NSC shows a typical specific capacity recovery phenomenon, an extraordinary capacity of 744.4 mAh g-1 at 2000 mA g-1 after 1000 cycles can be achieved, which outperforms most of the Fe7S8-based anode materials reported before. The Fe7S8-NSC should be a promising anode material for high-performance LIBs.

Lithium ion batteries have been widely used in the power-driven system and energy storage system. While thermal safety for lithium ion battery has been constantly concerned all over the world due to the thermal runaway problems occurred in recent years. Lithium ion battery has high temperature sensitivity and the relatively narrow operating temperature range because of the complex electrochemical reactions at different temperatures. And the temperature change, including the global temperature change in different seasons and the local temperature rise that is induced by its self-heating etc., can trigger side reactions and then lead to thermal runaway, which should be further considered to ensure thermal safety of lithium ion battery. This review summarizes the inducements of thermal runaway and relevant solutions, spanning a wide temperature range. The low temperature induced issues, such as capacity fade and lithium plating and dendrite, can cause internal short circuit (ISC), while as the temperature is above the critical temperature, the speeding of side reactions and reduction of lifespan (T ​> ​40 ​°C) and thermal runaway (T ​> ​90 ​°C) will be triggered. In order to solve the thermal issues in batteries, extensive approaches have been investigated to prevent the occurrence, propagation and deterioration of thermal runaway, from the perspective of material to the battery system. The triggered mechanism at a wide temperature range, key factors for thermal safety and the effective heat dissipation strategies are concluded in this review. This review is expected to offer effective thermal safety strategies and promote the development of lithium ion battery with high-energy density.

Thermal energy storage (TES) is among the most powerful tools to alleviate the risk of fossil energy depletion. Latent heat density and thermal conductivity are the two most important parameters to evaluate the performance of TES materials. In this work, for the first time, we embed knitting aryl network polymers (KAPs) on the skeleton of copper foam (CF) in a biomimetic protocol, where the preparation process is inspired by the growing process of a natural coral and the obtained phase change material (PCM)-holding medium exhibits a bird nest-type morphology. Excellent energy storage performance was determined, where the thermal conductivity was up to 55.37 W m−1 K−1 and the encapsulation rate could reach 62.1% without the observation of any enthalpy attenuation even after a 300 energy charging and releasing cyclization, due to the relatively high surface area, i.e., 1079.1 m2 g−1 and high thermal conductivity of the copper skeleton inside. Further study revealed the good applicable properties in terms of shape adjustability, light-to-thermal and light-to-electric conversion.

The liquid range of nanofluids is a crucial parameter as it intensively determines their application temperature scope. Meanwhile, improved thermal conductivity and stability are of great significa...

The thermostat-consistent fully coupled molecular dynamics–generalized fluctuating hydrodynamics method is developed for non-equilibrium water flow simulations. The model allows for strong coupling between the atomistic and the continuum hydrodynamics representations of water and shows an improved stability in comparison with the previous formulations of similar multiscale methods. Numerical results are demonstrated for a periodic nano-scale Poiseuille flow problem with SPC/E water. The computed time-averaged velocity profiles are compared with the analytical solution, and the thermal velocity fluctuations are well reproduced in comparison with the equilibrium molecular dynamics simulation. Several options to account for the long-range electrostatics interactions available in GROMACS are incorporated in the model and compared. It is demonstrated that the suggested non-equilibrium multiscale model is a factor of 4 to 18 faster in comparison with the standard all-atom equilibrium molecular dynamics model for the same computational domain size.