To realize high-energy-density Li metal batteries at low temperatures, a new electrolyte is needed to solve the high-voltage compatibility and fast lithium-ion de-solvation process. A gel polymer electrolyte with a small-molecular-weight polymer is widely investigated by combining the merits of a solid polymer electrolyte (SPE) and liquid electrolyte (LE). Herein, we present a new gel polymer electrolyte (P-DOL) by the lithium difluoro(oxalate)borate (LiDFOB)-initiated polymerization process using 1,3-dioxolane (DOL) as a monomer solvent. The P-DOL presents excellent ionic conductivity (1.12 × 10−4 S cm−1) at −20 °C, with an oxidation potential of 4.8 V. The Li‖LiCoO2 cell stably cycled at 4.3 V under room temperature, with a discharge capacity of 130 mAh g−1 at 0.5 C and a capacity retention rate of 86.4% after 50 cycles. Moreover, a high-Ni-content LiNi0.8Co0.1Mn0.1O2 (NCM811) cell can steadily run for 120 cycles at −20 °C, with a capacity retention of 88.4%. The underlying mechanism of high-voltage compatibility originates from the dense and robust B- and F-rich cathode interface layer (CEI) formed at the cathode interface. Our report will shed light on the real application of Li metal batteries under all-climate conditions in the future.

In terms of its ecological and sustainable nature, electrochemical nitrogen reduction reaction (e-NRR) is widely recognized as the ideal solution to replace conventional ammonia production techniques. Unfortunately, poor Faraday efficiency (FE) with lower e-NRR selectivity limits its large-scale application. Previous studies have identified Mo 2 C as an optimistic electrocatalyst for e-NRR, exhibiting great ammonia yield. However, Mo 2 C suffers from Mo leaching during the electrochemical reaction process, thus reducing the stability of the catalyst. Herein, we propose a new electrocatalyst based on first-principles calculations: HB/ alpha-Mo 2 C. This heterostructure is composed of Mo 2 C covered with a layer of Honeycomb Borophene (HB). The HB layer serves two purposes: to ensure the stability of the catalyst and improve the FE of the reaction. Our findings demonstrate the HB/ alpha-Mo 2 C performs the highest catalytic activity via a mixed mechanism with a limiting potential as low as -0.16 V, which was determined to be caused by the transfer of electrons from the active sites of the boron atoms to the adsorbate. Furthermore, the limiting potential of HER, a competing reaction, was found to be as high as -0.56 V, confirming the high efficiency of HB/ alpha-Mo 2 C towards e-NRR. This present work contributes to the development of new strategies for e-NRR catalyst design.

The development of effective catalysts consisting of double atoms presents a promising strategy towards achieving sustainable electrocatalytic nitrogen fixation. Here, using first principles calculations, we investigated electrocatalytic NRR performance of nine catalysts with TM double atoms sandwiched between graphdiyne and BN-doped graphdiyne (BN-TM2-G). Through the analysis on stability, charge population, electronic property and catalytic efficiency, BN-Fe2-G, BN-Co2-G and BN-Cu2-G were finally screened out for electrocatalytic NRR, with the lowest limiting potential of -0.55 V, -0.89 V and -0.43 V respectively, while the competitive HER is effectively inhibited. As a result of synergistic effect of double TM atoms, the catalytic activity of BN-TM2-G has been significantly improved compared to single metal catalysts BN-TM-G. This work will open up a novel strategy for systematic development of graphdiyne-based NRR catalysts with the aim of achieving enhanced efficiency.

Boosting the energy density and safety issue of lithium-ion batteries (LIBs) have become ever more important to satisfy the diverse applications. Herein, we present a new high voltage polyether-based electrolyte (HVPEE) by molecular design that can endure high-voltage operations and also present non-flammable features. Especially, HPVEEs show better compatibility and stability with electrode than conventional electrolyte. We find that the solvent separated ion pair (SSIP) and contact ion pair (CIP) dominate the ion-solvent structure of HPVEEs, rather than the free solvent and ions. In this way, the oxidative decomposition of HPVEE on the cathode interface can be suppressed significantly due to the lower highest occupied molecular orbital of SSIP complex structure than that of free TFSI - . As a result, the oxidation voltage can achieve as high as 5.35 V when the ether group/Li is optimized at 10/1 in the HVPEE, enabling the LiFePO 4 //Li full cell deliver a capacity of 165 mA h g -1 with a capacity retention of 98 % after 200 cycles. Moreover, when the cut-off voltage is 4.4 V, the discharge capacity of the LiNi 0.6 Mn 0.2 Co 0.2 O 2 //Li full cell can still reach 143 mA h g -1 after 80 cycles.

The huge Li ion transport resistance through the grain boundaries (GBs) among rigid oxide particles forces the adoption of high-temperature sintering (HTS) process over 1000 °C. Nevertheless, the severe side reactions and uncontrollable lithium loss are always companied during the high-cost HTS process, which slows down the pace of oxide solid electrolyte (OSE) for practical application and accelerates the exploration of a new OSE sintering process. Herein, a near-room-temperature (60 °C) cold-sintering process is proposed by filling the GBs with a low-melting-point plastic crystal electrolyte (PCE). Due to the soft property and high-ionic conductivity of PCE, the Li ion transport rate through the GBs is 10 times faster than the bulk phase, endowing the OSE (Li1.5Al0.5Ge1.5(PO4)3 chosen as a representative) with a room temperature ionic conductivity of 0.25 mS cm-1. As proof of the concept, the assembled Li symmetrical cells perform a low over-potential of 50 mV with a capacity of 1 mA h cm-2 and full cells delivers a capacity retention of roughly 70% after 820 cycles (1.5 years) at 0.1C.

Sarin, isopropyl methylphosphonofluoridate (C4H10O2FP), is a highly toxic nerve agent that can paralyze the central nervous system of human. The use of advanced materials with high adsorption capacity and easy regeneration for adsorbing sarin is an effective strategy to remove sarin. In the present work, we investigate sarin adsorption on TM-doped CNT(TM-CNT) by using DFT method (TM=Co, Cu, Cr, Fe, Mn, Ni, Zr). It is found that TM-CNT has a strong adsorption capacity for sarin molecule with the adsorption energy ranging from -1.55 to 2.11 eV. More important, the interaction between sarin molecule and adsorbent can be changed by applying an external electric field. When the added electric field is -0.005 a.u, adsorption energy became positive and sarin can release from the substrate easily. In addition, the adsorption of sarin changes the optical properties of the substrate obviously, which makes TM-CNT a promising candidate to detect sarin in the environment.

Solid-state polymer electrolytes are outstanding candidates for next-generation lithium metal batteries in the realm of high specific energy densities, high safeties and tight contact with electrodes. However, their applications are still hindered by the limitations that no single polymer is electrochemically stable with the oxidizing high-voltage cathode and the highly reductive Li anode, simultaneously. Herein, a bilayer asymmetric polymer electrolyte (SL-SPE) without accessional interface resistance that using poly (ethylene glycol) diacrylate (PEGDA) as a “bridge” to connect the sulfonyl (OS = O)-contained oxidation-tolerated layer and polyether-derived reduction-tolerated layer (SPE), is proposed and synthesized by sequential two-step UV polymerizations. SL-SPE can provide widened electrochemical stability window up to 5 V, while simultaneously deploying a stable Janus interface property. Eventually, the superior high-voltage (4.4 V) cycling durability can be displayed in LiNi0.6Co0.2Mn0.2O2|SL-SPE|Li batteries. This finding provides a bran-new idea for designing multifunctional polymer electrolytes in the application of solid-state batteries.

The brain-storm of designing low-cost and commercialized eutectic electrolytes for zinc (Zn)-based electrochemical energy storage (ZEES) remains unresolved and attractive, especially when implementing it at low temperatures. Here, we report an appealing layout of advancing chlorine-functionalized eutectic (Cl-FE) electrolytes via exploiting Cl anion-induced eutectic interaction with Zn acetate solutions. This novel eutectic liquid shows high affinity to collaborate with 1,3-dioxolane (DOL) and is prone to constitute Cl-FE/DOL-based electrolytes with a unique inner/outer eutectic solvation sheath for the better regulation of Zn-solvating neighboring and reconstruction of H-bonding. The side reactions are effectively restricted on Zn anodes and a high Coulombic efficiency of 99.5 % can be achieved over 1000 cycles at −20 °C with Zn//Cu setups. By prototyping scale-up Zn-ion pouch cells using the optimal eutectic liquid of 3ZnOAc 1.2 Cl 1.8 -DOL, we obtain improved electrochemical properties at −20 °C with a high capacitance of 203.9 F g −1 at 0.02 A g −1 in a range of 0.20–1.90 V and long-term cycling ability with 95.3 % capacitance retention at 0.2 A g −1 over 3,000 cycles. Overall, the proposal of ideal Cl-FE/DOL-based electrolytes guides the design of sub-zero and endurable aqueous ZEES devices and beyond.

A precise regulation approach of protic ether substitute in eutectic electrolytes has demonstrated enhanced electrochemical performance of supercapacitors implementation.

Green and sustainable electrochemical conversion and storage devices possess the nature to repress a negative effect on sustainability during energy conversion and storage. However, the sustainability of devices' components themselves (e.g., raw material abundance, eco-friendliness, and recycling) is often ignored, which may damage the environment and limit devices' practical applicability. Herein, guided by the concept of sustainability, a sustainable strategy is reported to synthesize the very cheap single zinc atoms dispersed on nitrogen- doped hierarchically porous carbon (SA-Zn-NHPC) with minimized environmental expense by employing abundant natural apples, natural egg whites, and relatively non-toxic ZnCl2 as raw materials. Theory calculations and experiments prove that Zn-N-4 within SA-Zn-NHPC is responsible for superior CO2 reduction reaction (CO2RR) activity with high CO Faradaic efficiency (96%) at low overpotential (0.33 V) and outstanding O-2 reduction reaction (ORR) activity with high half-wave potential (0.87 V) and high onset potential (1.00 V), which are among the best performance of single-atom catalysts. Additionally, remarkable activity and high stability of SA-Zn-NHPC for CO2RR and ORR as well as ultralow feedstock cost would render the recycling procedure for end-of-life catalysts (e.g., Pt within fuel cells) unrequired. The sustainability perspective-oriented strategy will bring major advances in both economical energy cost and environment protection.