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Graphite-like carbon nitride (g-C 3 N 4) has been regarded as a promising photocatalyst for solar-to-chemical conversion. Nevertheless, the narrow absorption of light extremely limited its photocatalytic performance under near-infrared (NIR) irradiation. Herein, the Cu 7. 2 S 4 with outstanding NIR absorption was successfully introduced to g-C 3 N 4 nanosheets through a simple in-situ growth procedure. As expected, the constructed Cu 7.2 S 4 /g-C 3 N 4 (CSCN) photocatalysts exhibit superior H 2 production activity of 82 μmol g−1 h−1 under NIR light irradiation (λ > 800 nm), which outperforms currently reported g–C 3 N 4 –based NIR-driven H 2 production systems. Especially, the optimal sample CSCN-5 displays a robust activity of 66 μmol g−1 h−1 at λ = 850 nm monochromatic light irradiation. The excellent photocatalytic performance is linked to the extended optical absorption as well as the efficient separation efficiency of photoinduced carriers, which are evidenced by the UV-visible absorption spectroscopy and photoelectrochemical test. This work provides an effective approach for constructing a Cu 7.2 S 4 /g-C 3 N 4 photocatalytic system for the transformation of NIR solar energy into hydrogen. The novel NIR-driven Cu 7. 2 S 4 /g-C 3 N 4 composite photocatalyst was constructed through a convenient in situ growth process. As expected, the outstanding photocatalytic H 2 yield was 82 μmol g−1 h−1 under the irradiation of NIR light (λ > 800 nm), which outperforms currently reported g–C 3 N 4 –based NIR-driven H 2 production systems. More significantly, the sample CSCN-5 shows an optimum activity (66 μmol g−1 h−1) under λ = 850 nm monochromatic light irradiation. This work provides a feasible approach for achieving g–C 3 N 4 –based photocatalyst NIR-induced superior solar-to-chemical conversion. [Display omitted] • Cu 7·2 S 4 modified g-C 3 N 4 is prepared by a facile hydrothermal treatment method. • The Cu 7·2 S 4 /g-C 3 N 4 composites show a superior optical adsorption from visible to NIR. • The Cu 7·2 S 4 /g–C 3 N 4 –5 composite exhibits excellent HER of 82 μmol g−1 h−1 (λ > 800 nm). • The HER of Cu 7·2 S 4 /g–C 3 N 4 –5 shows no obvious change after 4 runs within 20 h. [ABSTRACT FROM AUTHOR]

Abstract: In order to identify competitive ion-conducting materials in ceria-carbonates composite electrolytes, M-NLCO (M = Ce0.8Sm0.2O2-δ (SDC), Ce0.8Gd0.2O2-δ (GDC), Ce0.8Y0.2O2-δ (YDC); NLCO = 0.53Li2CO3–0.47Na2CO3) sintered at different temperatures (600° C, 625° C, 650° C, 675° C and 700° C) have been prepared and characterized. It is found that independent of systems, the 675° C-sintered composites in M-NLCO always present the highest conductivities because of the best NLCO distribution and interfacial microstructures. Moreover, among three composites (sintered at 675° C), the total () and grain boundary () conductivities measured at 600° C are ranked as: SDC-NLCO (, ) ﹥ GDC-NLCO (, ) ﹥ YDC-NLCO (, ), which is attributed to ionic-radius compatibility between the dopant and the host as well as the NLCO distribution and interfacial microstructures. It can be concluded that ionic-radius compatibility between the dopant and the host, NLCO distribution and interfacial microstructures have important effects on improving ionic conductivities for ceria-carbonates composite electrolytes. [Copyright &y& Elsevier]

In order to optimize the electrical properties of co-doped ceria electrolytes, Ce 0.8 Ca 0.15 Sm 0.05 O 2− δ (CCS) sintered at different temperatures (1150 °C, 1200 °C, 1250 °C, 1300 °C and 1350 °C for 8 h) have been prepared and systematically investigated. It is found that among these samples sintered at different conditions, the electrical conductivity ( σ ) measured at 800 °C can be ranked as: CCS 1250 °C : σ CCS 1250 ° C 800 ° C = 2.38 × 10 −2 S cm −1 > CCS 1200 °C : σ CCS 1200 ° C 800 ° C = 1.81 × 10 −2 S cm −1 > CCS 1150 °C : σ CCS 1150 ° C 800 ° C = 1.50 × 10 −2 S cm −1 > CCS 1300 °C : σ CCS 1300 ° C 800 ° C = 1.26 × 10 −2 S cm −1 > CCS 1350 °C : σ CCS 1350 ° C 800 ° C = 0.68 × 10 −2 S cm −1 . The electrical conductivity of CCS increases with the increase of sintering temperatures, and the 1250 °C-sintered sample presents the highest conductivity because of the best microstructures. However, the electrical conductivity of CCS decreases when the sintering temperatures goes beyond 1250 °C. We attribute this to the phase instability. It reveals that microstructures and the phase stability have important effects on the optimization of electrical properties for the co-doped ceria electrolytes. [ABSTRACT FROM AUTHOR]

Abstract: In order to optimize the electrical properties of co-doped ceria electrolytes, Ce0.8Ca0.15Sm0.05O2−δ (CCS) sintered at different temperatures (1150 °C, 1200 °C, 1250 °C, 1300 °C and 1350 °C for 8 h) have been prepared and systematically investigated. It is found that among these samples sintered at different conditions, the electrical conductivity (σ) measured at 800 °C can be ranked as: CCS1250 °C:  = 2.38 × 10−2 S cm−1 > CCS1200 °C:  = 1.81 × 10−2 S cm−1 > CCS1150 °C:  = 1.50 × 10−2 S cm−1 > CCS1300 °C:  = 1.26 × 10−2 S cm−1 > CCS1350 °C:  = 0.68 × 10−2 S cm−1. The electrical conductivity of CCS increases with the increase of sintering temperatures, and the 1250 °C-sintered sample presents the highest conductivity because of the best microstructures. However, the electrical conductivity of CCS decreases when the sintering temperatures goes beyond 1250 °C. We attribute this to the phase instability. It reveals that microstructures and the phase stability have important effects on the optimization of electrical properties for the co-doped ceria electrolytes. [Copyright &y& Elsevier]