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Cu(In,Al)(S,Se) 2 (CIASSe) films were prepared on soda lime glass substrates by sulfuring and selenizing co-sputtered Cu-In-Al metal precursors. CIASSe film preparation was optimized and the film properties were characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, and ultraviolet–visible spectroscopy. Films that were annealed for 20 min formed a single-phase chalcopyrite structure, and those films annealed at 500 °C and 540 °C exhibited a smooth and dense surface topography. After being annealed at 450–540 °C, films contained reduced amounts of copper and close to ideal stoichiometric compositions. Their absorption coefficients were over 10 4 cm −1 , and the obtained optical band gap values were 1.37 eV, 1.42 eV, and 1.44 eV, respectively, which were close to the ideal optical band gaps for photovoltaic applications. [ABSTRACT FROM AUTHOR]

Abstract: CuIn(S,Se)2(CISSe) thin films have been prepared onto soda-lime-glass (SLG) substrates by selenization and sulfurization of magnetron sputtered Cu–In precursors. The results indicate that the properties of the CISSe films are strongly dependent on the post-annealing treatment. After annealing at 400 °C for 20 min, the CISSe films have formed tetragonal (chalcopyrite) crystal structure and the diffraction peaks of the films shift systematically to the left with the temperature varying from 400 °C to 500 °C. EDAX study reveals that the compositions of CISSe films are Cu0.83In1.17S1.67Se0.3, Cu0.86In1.13S1.61Se0.4 and Cu0.82In1.15S1.54Se0.49 after annealing at 400 °C, 450 °C and 500 °C, respectively. The direct optical band gaps of the films slightly decrease from 1.44 ev to 1.32 ev with the increase of the temperature from 400 °C to 500 °C, and the optical absorption coefficient is over 105 cm−1. The films annealed at 400 °C–500 °C are all found to be p-type and the resistivity is almost 10−2–10−3 Ω cm. The carrier mobility of the film at 500 °C is almost as high as 1.701 cm2/V S. [Copyright &y& Elsevier]

Cu2ZnSn(S,Se)4 (CZTSSe) thin films were successfully prepared by selenization and sulfurization of Cu2ZnSnS4 (CZTS) nanocrystals synthesized by a single-step process with a new oleamide-based solution. The structure and properties of the CZTSSe thin films were characterized. The results indicated that the CZTSSe films had formed a single-phase structure at 450°C, and showed rich Cu, Sn and poor Zn compositions, and the Se element in CZTSSe increased with the increase of the annealing temperature. The films were all p-type, and that annealed at 500°C owned lower resistivity. In the visible light region, the films had strong optical absorption and the observed band gaps are 1.36eV and 1.32eV at 450°C and 500°C, respectively. [ABSTRACT FROM AUTHOR]

Ca 3 Co 4 O 9-δ (Ca349) cathode is prepared by sol-gel method and its performance on new Sm 0.075 Nd 0.075 Ce 0.85 O 2-δ (SNDC) electrolyte was evaluated as cathode for intermediate temperature solid oxide fuel cells (IT-SOFC). The crystal structure and chemical compatibility with SNDC electrolyte are studied by X-ray diffraction (XRD). The micromorphology and electrochemical performance of Ca349 with SNDC electrolyte are characterized. The formation of Ca349 phase and good chemical compatibility between Ca349 and SNDC electrolyte are confirmed by XRD. The Ca349 cathode sintered at 850 °C for 5 h shows the best cathode performance, the area specific resistances (ASR) of Ca349 cathode are found to be 0.236 Ω cm 2 at 800 °C, and the ASR can be further decreased by incorporating SNDC electrolyte. The composite (Ca349-50 wt% SNDC) gives the lowest ASR values (0.093 Ω cm 2 at 800 °C). Its ASR is improved by at least 60% compare to single-phase Ca349 cathode. At 800 °C, the maximal power density of anode-supported SOFCs with Ca349 cathode reaches 410.09 mW cm −2 . The total resistance of the cell was only 0.168 Ω cm 2 . These encouraging data show that Ca349 onto SNDC with good electrochemical performance could be promising as a cathode material of IT-SOFC. [ABSTRACT FROM AUTHOR]

Highlights • BaCo 0.7 Nb 0.2 Ta 0.1 O 3−δ (BCNT) cathode were prepared was prepared by solid phase reaction method. • The stability evaluation of the cathode showed the BCNT had sufficient stability during the operation. • Maximum power density of SDC electrolyte-supported cell reaches 626.41 mW·cm−2 at 800 °C. Abstract The BaCo 0.7 Nb 0.2 Ta 0.1 O 3−δ (BCNT) perovskite-type oxide was prepared by the conventional solid phase reaction method as a potential electrocatalyst for the oxygen reduction reaction. Its electrochemical properties were characterized. The results indicated that the BCNT oxide sintered at 1100 °C for 10 h had formed a single-phase cubic perovskite structure. And the BCNT–Sm 0.2 Ce 0.8 O 1.9 (SDC) mixture co-sintered at the same conditions showed good chemical compatibility and stability between BCNT and SDC. The BCNT cathode sintered at 1000 °C for 4 h on SDC electrolyte exhibited the lowest the polarization resistance (about 0.0495 Ω·cm2 at 800 °C). Moreover, with a 351 μm-thick SDC as electrolyte and BCNT as the cathode, maximum power densities of the single cell reached 466.81 and 626.41 mW·cm−2 at 750 and 800 °C, respectively, and the corresponding total interface polarization resistance of the cell were 0.0913 Ω·cm2 and 0.0552 Ω·cm2. Short-term stability of the cell showed that the cell was quite stable at 750 °C for 15 h. This suggested that BCNT was a very promising cathode material for IT-SOFCs. [ABSTRACT FROM AUTHOR]

• A novel CBP 0.4 C material is developed as a potential cathode of IT-SOFCs. • Doping with Pr ions can improve the electrochemical performance of the cathode. • Maximum power density of cell with CBP 0.4 C cathode reached 0.705 W/cm2 at 800 °C. The Ca 2.9−x Bi 0.1 Pr x Co 4 O 9−δ (CBP x C, x = 0–0.6) oxides were prepared by sol–gel method, as the potential cathode of anode-supported intermediate temperature solid oxide fuel cells (IT-SOFCs). The electrochemical performance test showed that the CBP x C oxide sintered at 700 °C for 10 h could form a single-phase crystal structure, and when the doping ratio of Pr ion was x = 0.4, the CBP x C cathode on the SDC electrolyte sintered at 950 °C for 5 h obtained the minimum interface polarization resistance (about 0.406 Ω·cm2 at 800 °C). Meanwhile, on the basis of the above conditions, we had fabricated Ni 0.95 Cu 0.05 O x -SDC/SDC/CBP 0.4 C single cell with the optimized CBP x C (x = 0.4) cathode, in which the SDC electrolyte thickness was 55.6 μm. The maximum power densities of the single cell reached 0.705 W/cm2 and 0.570 W/cm2 at 800 °C and 750 °C, the corresponding polarization resistances were 0.051 Ω·cm2 and 0.153 Ω·cm2, respectively. This suggested that CBP 0.4 C was a very promising cathode material for IT-SOFCs. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries have been explored extensively due to its abundant reserve and low cost. However, reports on full symmetric battery with the same electrode materials are relatively less than asymmetrical battery. In this work, symmetric sodium-ion battery based on layered P 2-Na 0.67 [Zn x Mn 1- x ]O 2 (x = 0.1, 0.2, 0.28, 0.34) as both positive and negative electrode materials are studied comprehensively. This active material shows two electrochemical working windows with reversible lattice oxygen redox and Mn4+/Mn3+ redox couple. The positive side Na 0.67 [Zn 0.28 Mn 0.72 ]O 2 provides a highly reversible capacity of 170 mAh g−1 at 0.05C (10 mA g−1) between 2.0–4.2 V and outstanding capacity retention of 77.2% after 100 cycles. Na 0.67 [Zn 0.28 Mn 0.72 ]O 2 electrode also exhibits excellent rate performance up to a high rate of 5C which is the best among the pure anionic-redox based cathodes. In addition, an average voltage of about 2.0 V versus Na+/Na is obtained as negative electrode material, with a reversible capacity of 99 mAh g−1. This full symmetric battery also exhibits excellent rate performance and cycle stability which are related to Zn doping. As a cost-effective element, zinc has been used as inactive atom to induce the anionic redox and enhance the crystal structure. This is the first time to explore symmetric sodium-ion battery with anionic redox. [ABSTRACT FROM AUTHOR]