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Lithium‐ion batteries (LIBs) suffer from energy loss and safety hazards under high‐rate conditions, because of the sluggish electrochemical kinetics and unstable interfacial passivation. Herein, a PC‐based electrolyte using weakly solvated solvent ethyl trifluoroacetate is developed to improve interfacial kinetics and stability in LIBs. A microsolvating competition is revealed in the bulk electrolyte, forming a loose Li+ coordination configuration with benign Li+ affinity and high ionic conductivity. Furthermore, an inorganic‐rich interphase is constructed on a graphite anode, affording smooth Li+ desolvation and reliable passivation. Consequently, the NCM622/graphite cell in PC‐based electrolyte shows improved cycling stability (82.2% after 200 cycles) and rate capability (83% at 4C compared to 0.1C) at a high‐voltage of 4.5 V, much better than those of EC‐based electrolyte (76.2% after 200 cycles and 74% at 4C). Additionally, the PC‐based electrolyte affords reversible operation at –40 °C while the EC‐based electrolyte fails at –40 °C. This work highlights the potential of solvation structure engineering for low‐energy‐barrier electrolyte. [ABSTRACT FROM AUTHOR]

The advancement of lithium‐ion batteries (LIBs) calls for superior electrolyte design to satisfy the booming demands of energy storage markets. Despite being typically indispensable in modern electrolytes, ethylene carbonate (EC) exhibits strong affinity with Li+ and derives organic‐rich SEI, leading to sluggish interfacial dynamics and unsatisfied rate capability. Here, we construct a kinetically favorable electrolyte based on linear carbonates (DMC) and fluoroethylene carbonate (FEC) with functional non‐solvating cosolvent, fluorobenzene (FB). Specifically, DMC and FEC, as weak binding solvents, show facile interfacial kinetics. FB enables a loose coordination chemistry through dipole‐dipole interaction, further lubricating Li+ desolvation and transport through SEI at interphase, which accelerates electrochemical kinetics and enables improved rate performance (257 mA h g−1 is achieved for graphite at 6 C). Moreover, the optimized electrolyte shows decent graphite compatibility, long‐term stability (75 % capacity retention after 350 cycles for NCM622/graphite pouch cells at 1 C) and wide‐temperature adaptability (−40~160 °C). This work reveals that dipole‐dipole interaction between non‐solvating cosolvents and solvents can effectively lower desolvation energy barrier and ultimately enable good rate capability, which provides a new avenue for designing EC‐free electrolyte in high‐rate LIBs. [ABSTRACT FROM AUTHOR]

Sulfurized polyacrylonitrile (SPAN), featuring uniform dispersion of short-chain sulfur in an organic skeleton, shows great promise in lithium–sulfur (Li–S) batteries due to the inhibited polysulfide dissolution and hence improved electrochemical performance. However, the practical applicability of SPAN is significantly limited by its relatively poor ionic and electronic conductivity, as well as sulfur content (<50%). Herein, triallyl isocyanurate (TI) is incorporated to fabricate SPAN fibers with robust chemical structure and high sulfur loading. The fine-tuned organosulfur cathode (Se0.05S0.95PAN-TI11, 1F) demonstrates increased S&Se content of 54.2% and excellent electrochemical performance in Li/Na–S batteries. As a result, 1F exhibits an ultrahigh composite capacity of 671 mA h g−1 at 0.1C (capacity retention up to 100%) and remarkable rate capability of 405 mA h g−1 at 8C in Li–S batteries. Additionally, 1F shows prolonged cycling ability over 300 cycles at 0.5C when applied in an RT-S battery. Notably, under harsh conditions (S&Se loading of 5.5 mg cm−2 and E/S&Se = 5 μL mg−1), the Li–1F battery displays a brilliant initial areal capacity of 8.0 mA h cm−2 at 0.1C (reversible capacity of 6.3 mA h cm−2) and retains a capacity of 5.3 mA h cm−2 at the 200th cycle (capacity retention of 84%). Consequently, 1F is promising for practical applications in high-performance metal–S batteries. [ABSTRACT FROM AUTHOR]

The introduction of 1,3,5-trifluorobenzene (F3B) as an additive for lithium-ion battery electrolytes can produce a LiF-rich solid electrolyte interface (SEI). Meanwhile, F3B has superior thermal stability compared with traditional fluorinated additives and is less likely to produce hydrogen fluoride to damage the cathode. [ABSTRACT FROM AUTHOR]

The operation of lithium‐ion batteries (LIBs) at low temperatures (<−20 °C) is hindered by the low conductivity and high viscosity of conventional carbonate electrolytes. Methyl acetate (MA) has proven to be a competitive low‐temperature electrolyte solvent with low viscosity and low freezing point, but its interfacial stability is poor and remains elusive until now. Here, it is revealed thaat the reductive stability of MA‐based electrolytes is fundamentally governed by the anion‐prevailed solvation structure. Based on this framework, fluorobenzene is employed in the electrolyte to promote the entry of anions into the solvation shell via dipole‐dipole interactions and the generation of free MA, thus enhancing the lowest unoccupied molecular orbital energy of MA. The designed electrolyte enables LiCoO2 (LCO)/graphite cells to exhibit excellent cycling performance at −20 °C (90% retention after 1000 cycles at 1 C) and to remain 91% of their room‐temperature capacity at a super‐low temperature of −60 °C at 0.05 C. Thanks to the plentiful free MA, this electrolyte has a high conductivity (2.61 mS cm−1) at −60 °C and allows LCO/graphite cell to charge at −60 °C. This study offers the possibility of practical applications for those solvents with poor reductive stability and provides new approaches to designing advanced electrolytes for low‐temperature applications. [ABSTRACT FROM AUTHOR]

Despite wide‐temperature tolerance and high‐voltage compatibility, employing propylene carbonate (PC) as electrolyte in lithium‐ion batteries (LIBs) is hampered by solvent co‐intercalation and graphite exfoliation due to incompetent solvent‐derived solid electrolyte interphase (SEI). Herein, trifluoromethylbenzene (PhCF3), featuring both specific adsorption and anion attraction, is utilized to regulate the interfacial behaviors and construct anion‐induced SEI at low Li salts' concentration (<1 m). The adsorbed PhCF3, showing surfactant effect on graphite surface, induces preferential accumulation and facilitated decomposition of bis(fluorosulfonyl)imide anions (FSI−) based on the adsorption–attraction–reduction mechanism. As a result, PhCF3 successfully ameliorates graphite exfoliation‐induced cell failure in PC‐based electrolyte and enables the practical operation of NCM613/graphite pouch cell with high reversibility at 4.35 V (96% capacity retention over 300 cycles at 0.5 C). This work constructs stable anion‐derived SEI at low concentration of Li salt by regulating anions–co‐solvents interaction and electrode/electrolyte interfacial chemistries. [ABSTRACT FROM AUTHOR]

The self‐exothermic in early stage of thermal runaway (TR) is blasting‐fuse for Li‐ion battery safety issues. The exothermic reaction between lithiated graphite (LiCx) and electrolyte accounts for onset of this behavior. However, preventing the deleterious reaction still encounters hurdles. Here, we manage to inhibit this reaction by passivating LiCx in real time via targeted repair of SEI. It is shown that 1,3,5‐trimethyl‐1,3,5‐tris(3,3,3‐trifluoropropyl)cyclotrisiloxane (D3F) can be triggered by LiCx to undergo ring‐opening polymerization at elevated temperature, so as to targeted repair of fractured SEI. Due to the high thermal stability of polymerized D3F, exothermic reaction between LiCx and electrolyte is inhibited. As a result, the self‐exothermic and TR trigger temperatures of pouch cell are increased from 159.6 and 194.2 °C to 300.5 and 329.7 °C. This work opens up a new avenue for designing functional additives to block initial exothermal reaction and inhibit TR in early stage. [ABSTRACT FROM AUTHOR]

The self‐exothermic in early stage of thermal runaway (TR) is blasting‐fuse for Li‐ion battery safety issues. The exothermic reaction between lithiated graphite (LiCx) and electrolyte accounts for onset of this behavior. However, preventing the deleterious reaction still encounters hurdles. Here, we manage to inhibit this reaction by passivating LiCx in real time via targeted repair of SEI. It is shown that 1,3,5‐trimethyl‐1,3,5‐tris(3,3,3‐trifluoropropyl)cyclotrisiloxane (D3F) can be triggered by LiCx to undergo ring‐opening polymerization at elevated temperature, so as to targeted repair of fractured SEI. Due to the high thermal stability of polymerized D3F, exothermic reaction between LiCx and electrolyte is inhibited. As a result, the self‐exothermic and TR trigger temperatures of pouch cell are increased from 159.6 and 194.2 °C to 300.5 and 329.7 °C. This work opens up a new avenue for designing functional additives to block initial exothermal reaction and inhibit TR in early stage. [ABSTRACT FROM AUTHOR]

The advancements of lithium‐ion batteries indubitably call for advanced electrolytes with superior environmental adaptability and long‐term stability. Propylene carbonate (PC) proves to be a competitive solvent with the high permittivity and wide‐liquid range, while the application is intrinsically hindered by the poor graphite compatibility and high viscosity. Here, a PC‐based electrolyte with wide‐temperature range is developed by tuning the strength and topology of the Li+‐PC interactions via non‐solvating interactions without altering the solvation structure. Thus, the problem of graphite exfoliation caused by Li+‐PC co‐intercalation can be successfully mitigated. Consequently, such electrolyte shows compatibility with both graphite and high‐nickel cathode, exhibiting an expanded liquid range from −90 to 90 °C. This work, breaking from the traditional EC‐based formula, provides a new strategy for designing PC‐enabled electrolyte featuring high performance, wide‐temperature compatibility, and sustainability [ABSTRACT FROM AUTHOR]

The indium thiospinels In2S3 and MgIn2S4 are promising host for the intermediated band (IB) photovoltaic materials due to their ideal band gap value. Here, the optical properties and electronic structure of Fe-doped In2S3 and MgIn2S4 have been investigated. All the Fe-substituted semiconductors exhibit two additional absorption bands at about 0.7 and 1.25 eV, respectively. The results of first-principles calculations revealed that the Fe substituted at the octahedral In site would introduce a partially filled IB into the band gap. Thanks to the formation of IB, the Fe-substituted semiconductors have the ability to absorb the photons with energies below the band gap. With the wide-spectrum absorption of solar energy, these materials possess potential applications in photovoltaic domain. [ABSTRACT FROM AUTHOR]

A novel titanium–silicon MOF precursor was first designed and constructed via a facile solvothermal process. After subsequent pyrolysis, the derived ternary TiO2/SiOx@C nanocomposite exhibited superior lithium storage performances, which was attributed to their all-in-one architecture of synergistic components, including stable-cycling nanostructured TiO2, high-capacity SiOx and high-conductivity carbon matrix. [ABSTRACT FROM AUTHOR]

Keywords: lithium-ion batteries; molecular interactions; PC-based electrolytes; solvation structures; wide-temperature electrolytes EN lithium-ion batteries molecular interactions PC-based electrolytes solvation structures wide-temperature electrolytes 1 1 1 12/27/22 20221222 NES 221222 B Lithium-Ion Batteries b In article number 2201801, Ziqi Zeng, Jia Xie, and co-workers report that the non-solvating interactions within electrolytes can be employed to tune the strength and topology of Li SP + sp -propylene carbonate (PC), which enhances the graphite compatibility of PC-based electrolytes over a wide temperature range and high voltage. Rejuvenating Propylene Carbonate-based Electrolyte Through Nonsolvating Interactions for Wide-Temperature Li-ions Batteries (Adv. Lithium-ion batteries, molecular interactions, PC-based electrolytes, solvation structures, wide-temperature electrolytes. [Extracted from the article]

A simple, safe, and clean molecular precursor-based solution method was developed to fabricate a Cu(In,Ga)(S,Se)2 absorber layer. Low-cost and versatile thioacetic acid was deployed as an effective solvent and suitable sulfur source to dissolve the starting materials, generating a high power conversion efficiency of 8.6% in the final cell. [ABSTRACT FROM AUTHOR]

Low-cost and high-yield preparation of CuInSe2 films is the bottleneck for promising CuInSe2-based thin film solar cells. Here, we developed a simple, safe and cost-effective method using thioacetic acid to fabricate the absorber films of CuIn(S,Se)2 (CISSe). Dissolution of Cu2O and In(OH)3 in thioacetic acid was attributed to the strong coordination ability of S. The adhesive precursor solution can be prepared without any heating, centrifugation and inert gas protection, superior to the previously reported methods. The precursor CISSe layer was easily deposited in air by spin coating to ensure low cost. Uniform and compact CISSe thin films with well-crystallized and pure-phased CISSe grains were obtained after one step annealing. The as-prepared CISSe thin films were successfully applied to solar cells and a energy conversion efficiency of 6.75% was achieved. This facile preparation provides a low-cost and easy method to fabricate Cu-based thin film solar cells. [ABSTRACT FROM AUTHOR]

An intermediate-band (IB) semiconductor CuGa1− xCr xS2 was investigated by the self-consistent many-body GW approach (sc GW) and further confirmed by the experimental results. The Cr dopant introduced a partially occupied IB, and the density-of-states analysis indicates the electron transfer between the impurities and host lattice would suppress the non-radiative recombination. The CuGa1− xCr xS2 was synthesized by a high-temperature solid-state reaction and the X-ray photoelectron spectroscopy (XPS) indicated the presence of Cr3+. Due to the Cr dopant, two additional absorption responses were directly observed in the UV-Vis-NIR absorption spectrum. The further photocatalytic investigations verified the IB absorptions could produce highly mobile electrons and holes to degrade dyes. This material leads to lower-energy photon absorption, which could be a promising candidate for the high-efficiency solar cells. [ABSTRACT FROM AUTHOR]

Coordination compounds such as Prussian blue and its analogues are acknowledged as promising candidates for electrochemical sodium storage owing to their tailorable and open frameworks. However, a key challenge for these electrode materials is the trade‐off between energy and power. Here, it is demonstrate that Prussian white (Na3.1Fe4[Fe(CN)6]3) hierarchical nanotubes with fully open configurations render extrinsic Na+ intercalation pseudocapacitance. The cathode exhibits a capacity up to 83 mA h g−1 at an ultrahigh rate of 50 C and an unprecedented cycle life over 10 000 times for sodium storage. In situ Raman spectroscopy together with in situ X‐ray diffraction analysis reveal that intercalation pseudocapacitance enables full reaction of N‐FeIII/FeII sites in Prussian white with a negligible volume expansion (<2.1%). The discovery of surface‐controlled charge storage occurring inside the entire bulk of intercalation cathodes paves a new way for developing high power, high energy, and long life‐span sodium‐ion batteries. Prussian white hierarchical nanotubes with surface‐controlled charge storage are first developed based on a self‐template method. On the strength of this change storage mechanism, the cathode achieves an outstanding rate capability (83 mA h g−1 at 50 C) and an unprecedented cycling stability (65% after 10 000 cycles) for sodium storage. [ABSTRACT FROM AUTHOR]

Soft carbon has attracted tremendous attention as an anode in rocking‐chair batteries owing to its exceptional properties including low‐cost, tunable interlayer distance, and favorable electronic conductivity. However, it fails to exhibit decent performance for sodium‐ion storage owing to difficulties in the formation of sodium intercalation compounds. Here, microporous soft carbon nanosheets are developed via a microwave induced exfoliation strategy from a conventional soft carbon compound obtained by pyrolysis of 3,4,9,10‐perylene tetracarboxylic dianhydride. The micropores and defects at the edges synergistically leads to enhanced kinetics and extra sodium‐ion storage sites, which contribute to the capacity increase from 134 to 232 mAh g−1 and a superior rate capability of 103 mAh g−1 at 1000 mA g−1 for sodium‐ion storage. In addition, the capacitance‐dominated sodium‐ion storage mechanism is identified through the kinetics analysis. The in situ X‐ray diffraction analyses are used to reveal that sodium ions intercalate into graphitic layers for the first time. Furthermore, the as‐prepared nanosheets can also function as an outstanding anode for potassium‐ion storage (reversible capacity of 291 mAh g−1) and dual‐ion full cell (cell‐level capacity of 61 mAh g−1 and average working voltage of 4.2 V). These properties represent the potential of soft carbon for achieving high‐energy, high‐rate, and low‐cost energy storage systems. Defect‐rich microporous soft carbon nanosheets are synthesized via a facile microwave induced exfoliation strategy. The as‐designed nanosheets can function as outstanding anodes for sodium‐ion battery (232 mAh g−1), potassium‐ion battery (291 mAh g−1), and dual‐ion full battery (cell‐level capacity of 61 mAh g−1). [ABSTRACT FROM AUTHOR]