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Solid polymer electrolytes have been considered as promising candidates for solid-state batteries (SSBs), owing to their excellent interfacial compatibility and high mechanical toughness; however, they suffer from intrinsic low ionic conductivity (lower than 10−6 S/cm) and large thickness (usually surpassed over 100 μm or even 500 μm), which has a negative influence on the interface resistance and ionic migration. In this work, ceria quantum dot (CQD)-modified composite polymer electrolyte (CPE) membranes with a thickness of 20 μm were successfully manufactured via 3D printing technology. The CQD fillers can reduce the crystallinity of the polymer, and the oxygen vacancies on CQDs can facilitate the dissociation of ion pairs in the NaTFSI salt to release more free Na+, improving the ionic conductivity. Meanwhile, tailoring the thickness of the CPE-CQDs membrane via 3D printing can further promote the migration and transport of Na+. Furthermore, the printed NNM//CPE-CQDs//Na SSB exhibited outstanding rate capability and cycling stability. The combination of CQD modification and thickness tailoring through 3D printing paves a new avenue for achieving high performance solid electrolyte membranes for practical application in Na SSBs.

Developing argyrodite-type, chlorine-rich, sodium-ion, solid-state electrolytes with high conductivity is a long-term challenge that is crucial for the advancement of all-solid-state batteries (ASSBs). In this study, chlorine-rich, argyrodite-type Na6−xPS5−xCl1+x solid solutions were successfully developed with a solid solution formation range of 0 ≤ x ≤ 0.5. Na5.5PS4.5Cl1.5 (x = 0.5), displaying a highest ionic conductivity of 1.2 × 10−3 S/cm at 25 °C, which is more than a hundred times higher than that of Na6PS5Cl. Cyclic voltammetry and electrochemical impedance spectroscopy results demonstrated that the rich chlorine significantly enhanced the ionic conductivity and electrochemical stability, in addition to causing a reduction in activation energy. The Na5.5PS4.5Cl1.5 composite also showed the characteristics of a pure ionic conductor without electronic conductivity. Finally, the viability of Na5.5PS4.5Cl1.5 as a sodium electrolyte for all-solid-state sodium batteries was checked in a lab-scale ASSB, showing stable battery performance. This study not only demonstrates new composites of sodium-ionic, solid-state electrolytes with relatively high conductivity but also provides an anion-modulation strategy to enhance the ionic conductivity of argyrodite-type sodium solid-state ionic conductors. [ABSTRACT FROM AUTHOR]

A high capacitance and widened voltage frames for an aqueous supercapacitor system are challenging to realize simultaneously in an aqueous medium. The severe water splitting seriously restricts the narrow voltage of the aqueous electrolyte beyond 2 V. To overcome this limitation, herein, we proposed the facile wet-chemical synthesis of a new CuSe-TiO2-GO ternary nanocomposite for hybrid supercapacitors, thus boosting the specific energy up to some maximum extent. The capacitive charge storage mechanism of the CuSe-TiO2-GO ternary nanocomposite electrode was tested in an aqueous solution with 3 M KOH as the electrolyte in a three-cell mode assembly. The voltammogram analysis manifests good reversibility and a remarkable capacitive response at various currents and sweep rates, with a durable rate capability. At the same time, the discharge/charge platforms realize the most significant capacitance and a capacity of 920 F/g (153 mAh/g), supported by the impedance analysis with minimal resistances, ensuring the supply of electrolyte ion diffusion to the active host electrode interface. The built 2 V CuSe-TiO2-GO||AC-GO||KOH hybrid supercapacitor accomplished a significant capacitance of 175 F/g, high specific energy of 36 Wh/kg, superior specific power of 4781 W/kg, and extraordinary stability of 91.3% retention relative to the stable cycling performance. These merits pave a new way to build other ternary nanocomposites to achieve superior performance for energy storage devices. [ABSTRACT FROM AUTHOR]

Considering that both La2Fe14B and Ce2Fe14B compounds exhibit similar weak temperature-dependent anisotropic fields (HA) as Y2Fe14B, this work aims to clarify the elevated temperature behavior of melt-spun nanocrystalline La- or Ce-partially substituted stoichiometric Y2Fe14B alloys containing no critical rare earth elements. The results show that La-substituted (Y1−xLax)2Fe14B alloys (x = 0–0.5) show exceptional elevated temperature behavior, manifested by the increased coercivity with increasing temperature. For the Ce-substituted (Y1−xCex)2Fe14B alloys, only x = 0.1 and 0.2 alloys show the similar trend. Both the temperature coefficient of remanence α and coercivity β can be improved by La-substituted, indicating partial substitution La can effectively enhance the thermal stability of Y2Fe14B alloy. However, excess La or Ce substitution would reduce α and β value, resulting in the deterioration of thermal stability. Highest β values of 0.05 and − 0.08 have been obtained in (Y0.9La0.1)2Fe14B alloy at 300–400 K and (Y0.8La0.2)2Fe14B alloy at 300–500 K, respectively. In addition, Ce substitution can effectively enhance the coercivity of Y2Fe14B alloy at room temperature and La substitution does not show a beneficial effect on the room-temperature magnetic properties. This work is beneficial for developing high-performance/cost ratio permanent magnets based on abundant rare earth elements with superior thermal stability. [ABSTRACT FROM AUTHOR]

Flexible supercapacitors (SCs) have shown great potential for portable electronic devices due to ultra-long lifetime and high power characteristics. However, low energy densities of SCs hinder their practical applications. Herein, mesoporous C60 fullerene micro-particles (mCF) are prepared using Krätschmer-Huffman method, followed by solvent extraction and column chromatography for purification. The as-prepared mCF is characterized by XRD, EIMS, XPS, EDX, SEM, Raman spectroscopy and BET analysis, respectively. The mCF supported on carbon cloth (mCF@CC) is used as the electrode to study charge storage properties. The mCF@CC exhibits excellent capacitance of 440 F/g at 2 A/g, good rate capability of 84.85% at high current density of 12 A/g and stable life up to 10000 cycles. Additionally, the mCF@CC electrode possesses good flexible characteristics and presents almost same performance after 1000 bending cycles. Thus, mesoporous C60 fullerene micro-particles can be employed as negative electrode material for the flexible next generation supercapacitors. [ABSTRACT FROM AUTHOR]

Genetic effects on grain yield (GY) were determined in four wheat crosses using mixed inheritance model. GY in cross 1 was controlled by Model E while it was under control of Model E-1 in other crosses. Additive effects of two major genes were observed in cross 1 while additive effects due to several polygene and negative additive effects related to the major genes were observed in controlling GY in the rest of the crosses. Transgressive segregates in the segregating populations of all the crosses indicated the presence of favorable and adverse genes in the parents for GY. Major genes heritability was higher than that of the polygene in the segregating populations of all the crosses with highest environmental influence. Additively controlled nature of the trait predicts that selection of desirable recombinants for higher GY may be delayed up to advance generations until favorable genes are accumulated in homozygous condition. [ABSTRACT FROM AUTHOR]

A high capacitance and widened voltage frames for an aqueous supercapacitor system are challenging to realize simultaneously in an aqueous medium. The severe water splitting seriously restricts the narrow voltage of the aqueous electrolyte beyond 2 V. To overcome this limitation, herein, we proposed the facile wet-chemical synthesis of a new CuSe-TiO 2 -GO ternary nanocomposite for hybrid supercapacitors, thus boosting the specific energy up to some maximum extent. The capacitive charge storage mechanism of the CuSe-TiO 2 -GO ternary nanocomposite electrode was tested in an aqueous solution with 3 M KOH as the electrolyte in a three-cell mode assembly. The voltammogram analysis manifests good reversibility and a remarkable capacitive response at various currents and sweep rates, with a durable rate capability. At the same time, the discharge/charge platforms realize the most significant capacitance and a capacity of 920 F/g (153 mAh/g), supported by the impedance analysis with minimal resistances, ensuring the supply of electrolyte ion diffusion to the active host electrode interface. The built 2 V CuSe-TiO 2 -GO||AC-GO||KOH hybrid supercapacitor accomplished a significant capacitance of 175 F/g, high specific energy of 36 Wh/kg, superior specific power of 4781 W/kg, and extraordinary stability of 91.3% retention relative to the stable cycling performance. These merits pave a new way to build other ternary nanocomposites to achieve superior performance for energy storage devices.