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A series of Sm3+-activated Ca3Gd(AlO)3(BO3)4 red-emitting phosphors were prepared by a traditional high-temperature solid-state approach. They were characterized by XRD refinements, TEM, SEM, EDS, DRS, FTIR, Raman spectra, photoluminescence (PL) spectra, and fluorescence decay curves. The microstructure of the cation-borate phosphors and the presence of Sm3+ dopants, and their impact at the Ca and Gd sites were studied. All the samples exhibited bright red emissions caused by intra-4f transitions of Sm3+ ions when excited at 404 nm. The optimum dopant concentration was 4mol%, and the concentration quenching (CQ) process was driven by dipole-dipole interaction using Inokuti-Hirayama, and Dexter theories. Interestingly, the temperature-dependent PL spectra manifested that the resulting phosphor had excellent thermal stability with an activation energy of 0.234 eV. Ultimately, the investigated phosphor demonstrated excellent chemical stability. The Sm3+-doped CGAB:Sm3+ phosphor can convert NUV LED chips into intense red emission with Commission Internationale de l’Eclairage (CIE) diagrams of 0.615, 0.382 and high color purity of up to 95.6%. The WLED containing CG0.96AB:0.04Sm3+ merged with the commercial phosphors revealed low correlated color temperature (CCT≈4197 K) and high color rendering index (CRI≈89.7).

Laminate TiS2 nanosheets were successfully constructed for the electrochemical synthesis of valuable primary amines using biomass-derived furfurals at mild temperature and pressure.

The conductive metal-organic frameworks (MOFs) are suggested as the ideal electrocatalysts for hydrogen evolution reaction (HER) because of the high utilization of metal atoms. Rational design and facile synthesis of MOFs with large specific surface area, proper metals as center, and tunable chemical components is still full of challenges. Herein, we report the facile synthesis three types of porous MOFs by regulating metal center using benzene-1,3,5-tricarboxylic acid (H3BTC) as organic ligand and have successfully synthesized the rhombic octahedral Cu-BTC, rod-shaped Co-BTC and spherical Ni-BTC materials with large specific surface area ranged in 350-500 m2 g−1. These as-prepared MOFs materials exhibit high performance of HER in 0.5 M H2SO4. Ni-BTC material exhibits the lowest overpotential of 53 mV at 10 mA cm-2 and the smallest Tafel slope of 62 mV dec−1 than those of Cu-BTC (270 mV, 155 mV dec−1) and Co-BTC (123 mV, 100 mV dec−1), which are much superior to these previously reported MOFs catalysts. In addition, the fast catalytic kinetic of Ni-BTC was confirmed by the smaller charge transfer resistance (Rct) value of 0.9 Ω and larger electrochemical active surface area (ECSA) of 35.5 cm2 than those of Cu-BTC (8.2 Ω, 22.5 cm2) and Co-BTC (1.9 Ω, 27.7 cm2). Because of the structural advantage and large ECSA, the turnover frequency (TOF) value of Ni-BTC reaches up to 0.041 s−1 at 120 mV overpotential, which is 20.5 and 2.6 times greater than that of Cu-BTC (0.002 s−1) and Co-BTC (0.016 s−1). Besides, these three types of MOFs exhibited excellent durability over 12 h. This study unfolds diverse insights into the design and facile synthesis of MOFs for electrochemical energy conversion system.

Here, we report the effect of electron doping Zn for Cu on the physical properties of Cu0.5IrTe2. Slight Zn doping concentration (x) becomes detrimental to the charge density wave (CDW) order, whil...

In disordered transition-metal dichalcogenide (TMD) superconductor, both the strong spin-orbit coupling (SOC) and disorder show remarkable effects on superconductivity. However, the features of SOC and disorder were rarely detected directly. Here we report the quantum transport behaviors arising from the interplay of SOC and disorder in the TMD superconductor 1T-NbSeTe. Before entering the superconducting state, the single crystal at low temperature shows a resistivity upturn, which is T1/2 dependent and insensitive to the applied magnetic fields. The magnetoresistance (MR) at low temperatures shows a H1/2 dependence at high magnetic fields. The characteristics are in good agreement with the electron-electron interaction (EEI) in a disordered conductor. In addition, the upturn changes and MR at low magnetic fields suggest the contribution of weak antilocalization (WAL) effect arising from the strong SOC in the material. Moreover, the quantitative analyses of the transport features in different samples imply anomalous disorder-enhanced superconductivity that needs to be further understood. The results reveal the disorder enhanced EEI and the strong SOC induced WAL effect in 1T-NbSeTe, which illustrate the resistivity minimum in the widely studied doped superconductors. The work also provides insights into the disorder effect on the superconductivity.

We report the path from the charge density wave (CDW)-bearing superconductor CuIr

In this study, we determined the effect of doping with the noble metal Ag on Ir$_2$Te$_4$ superconductors. Based on the resistivity, magnetization, and heat capacity, we explored the changes in the superconductivity and charge density wave for Cu$_{1-x}$Ag$_x$Ir$_2$Te$_4$ as a function of isoelectric substitution. We assessed a complete set of competing states from suppressed charge density wave in the low doping region to superconductor in the middle doping region and re-entrant charge density wave in the high doping region, thereby obtaining an electronic phase diagram, where the superconducting dome was near bipartite charge density wave regions with a maximum superconducting temperature Tc of about 2.93 K at an Ag doping level of 12%. The lower H$_{c1}$ and upper H$_{c2}$ critical magnetic fields were determined for some representative samples in the Cu$_{1-x}$Ag$_x$Ir$_2$Te$_4$ series based on magnetization and resistivity measurements, respectively. We showed that H$_{c1}$ decreased whereas H$_{c2}$ increased as the doping content increased. The specific heat anomalies at the superconducting transitions $\Delta C_{el}/\gamma T_c$ for representative samples comprising Cu$_{0.92}$Ag$_{0.08}$Ir$_2$Te$_4$, Cu$_{0.88}$Ag$_{0.12}$Ir$_2$Te$_4$, and Cu$_{0.85}$Ag$_{0.15}$Ir$_2$Te$_4$ were approximately 1.40, 1.44, and 1.42, respectively, which are all near the Bardeen-Cooper-Schrieffer value of 1.43 and they indicate bulk superconductivity in these compounds., Comment: 35 pages, 6 figures, 3 tables;The manuscript with the same title will be published by Journal of Physics and Chemistry of Solids

We report the anomalous charge density wave (CDW) state evolution and dome-like superconductivity (SC) in CuIr2Te4-xSex series. Room temperature powder X ray-diffraction (PXRD) results indicate that CuIr2Te4-xSex compounds retain the same structure as the host CuIr2Te4 and the unit cell constants a and c manifest a linear decline with increasing Se content. Magnetization, resistivity and heat capacity results suggest that superconducting transition temperature (Tc) exhibits a weak dome-like variation as substituting Te by Se with the maximum Tc = 2.83 K for x = 0.1 followed by suppression in Tc and simultaneous decrease of the superconducting volume fraction. Unexpectedly, the CDW-like transition (TCDW) is suppressed with lower Se doping but re-emerges at higher doping. Meanwhile, the temperature-dependent XRD measurements show that the trigonal structure is stable at 20 K, 100 K and 300 K for the host sample and the doping composition with x = 0.5, thus we propose that the behaviour CDW-like transition arises from the disorder effect created by chemical doping and is not related to structural transition. The lower and the upper critical fields of these compounds are also addressed., The manuscript with the same title will be published by Superconductor Science and Technology, 2021

Ceramic dual-phase oxygen transport membranes with the composition of 60 wt% Ce0.9Pr0.1O2-δ-40 wt%Pr0.6Sr0.4Fe1-xAlxO3-δ (x = 0.05, 0.1, 0.2, 0.3, 0.4, 0.6, 0.8, 1.0) (60CPO-40PSF1-xAxO) based on 60Ce0.9Pr0.1O2-δ-40Pr0.6Sr0.4FeO3-δ doped Al was successfully synthesized through a modified Pechini method. Crystal structure, surface microtopography and oxygen permeability are investigated systematically. The cell parameters of perovskite phase first increased and then decreased with the increase of Al content, which is related to the radius of the Al3+ and the formation of impurity phase. As x ranges from 0.1 to 0.8, the oxygen permeability of the materials first increases and then decreases, and the maximum value of oxygen permeation rate for 60CPO-40PSF1-xAxO membranes with 0.4 mm thickness at 1000 °C is 1.12 mL min−1 cm−2 when x = 0.4. XRD measurements revealed high temperature stability and CO2-tolerant property of the dual-phase composites. The partial replacement of Fe3+/Fe4+ by Al3+ causes the material not only to exhibit good stability, but also to increase the oxygen permeability of the membranes.

The interplay between superconductivity (SC) and the charge density wave (CDW)-like order in CuIr2Te4 is systematically explored through Se substitution for Te site through the powder X-ray diffraction (PXRD), magnetic susceptibility, resistivity measurements and heat capacity. CuIr2Te4-XSex (0 ≤ x ≤ 0.5) compounds retain the same structure as the host CuIr2Te4. The unit cell parameters a and c decrease linearly with increasing Se content. Tc exhibits a weak dome-like variation as substituting Te by Se with the maximum Tc = 2.83 K for x = 0.1 followed by suppression in Tc and simultaneous decrease of the superconducting volume fraction. Unexpectedly, the CDW-like transition (TCDW) is suppressed with lower Se doping (0.025 ≤ x ≤ 0.2) but re-emerge at higher doping (0.25 ≤ x ≤ 0.5). We propose that it arises from the disorder effect by chemical doping. The lower and the upper critical field and these compounds are also addressed.

Ceramic composite oxygen transport membranes 60 wt%Ce0.9Pr0.1O2−δ–40 wt%Pr0.6Ca0.4Fe1−xCoxO3−δ (0 ≤ x ≤ 1) were synthesized via the Pechini one-pot method. X-ray diffraction patterns indicated that membranes of all compositions maintained the same crystal structure at the room temperature, whereas with the decrease in the Fe/Co ratio, it was more easier to find phase decomposition under Ar environment at an elevated temperature. SEM images demonstrate that the mechanical compatibility of the two phases becomes worse and the grain size gradually increases with the increase in the Co content. Oxygen permeability test results showed that the reduction in the Fe/Co ratio improved the oxygen permeability of the membrane for x ≤ 0.6, while the reduction in the Fe/Co ratio had an adverse impact on the oxygen permeability for x ≥ 0.8. Among all the composition membranes, 60 wt%Ce0.9Pr0.1O2−δ–40 wt%Pr0.6Ca0.4Fe0.4Co0.6O3−δ membrane possessed the highest permeation flux of about 0.85 mL min−1 cm−2 at 1000 °C under air/He atmosphere. The final stability testing indicated that it possessed good stability under air/He, and thereby has potential application prospects in high temperature oxygen consumption industries.

We report the path from the charge density wave (CDW)-bearing superconductor CuIr2Te4 to the metal insulator transition (MIT)-bearing compound CuIr2S4 by chemical alloying with the gradual substitution of S for Te. The evolution of structural and physical properties of the CuIr2Te4-xSx polycrystalline system with the doping range from 0 to 4 is systemically examined. The X-ray diffraction (XRD) results imply CuIr2Te4-xSx in the range between 0 and 0.5 crystallizes in a NiAs defected trigonal structure, whereas it adapts to the cubic spinel structure in the doping range from 3.6 to 4 and it is a mixed phase in the doping range from 0.5 to 3.6. Unexpectedly, the resistivity and magnetization measurements reveal that small-concentration S substitution for Te can suppress the CDW transition, but it reappears around x = 0.2, and the CDW transition temperature enhances clearly as x augments in the range from 0.2 to 0.5. Besides, the superconducting critical temperature (Tc) first increases with S doping content and then decreases after reaching a maximum Tc = 2.82 K for CuIr2Te3.85S0.15. MIT order has been observed in the spinel region from 3.6 to 4 associated with TMI increasing with x increasing. Finally, the rich electronic phase diagram of temperature versus x for this CuIr2Te4-xSx system is assembled, where the superconducting dome is associated with the suppression and re-emergence of CDW as well as MIT states at the end upon sulfur substitution in the CuIr2Te4-xSx chalcogenides., Comment: 33 pages, 8 figures, 4 tables; The manuscript with the same title will be published by JOURNAL OF PHYSICS-CONDENSED MATTER

In the progress of LED phosphors, the chemical stability, thermal stability, and color purity was not usually given due attention. However, the most critical problems of WLEDs are the deficit in the red-spectral region, stability, low color-rendering index (CRI) and high correlated color temperature (CCT) limit its efficiency for vivid application. Herein, the Ca3YGa3B4O15:xSm3+ (CYGB:xSm3+) were prepared by a solid-state route. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), diffuse reflection spectroscopy (DRS), and as well as photoluminescence (PL) spectra are used to exemplify the resulting samples. The structure and the Sm3+ dopants in the cation-borate phosphors were quantified, signifying the importance at Ca and Y sites. Under ultraviolet radiation-induced bright deep-red emissions with high color-purity up to 97.5%. The energy-migration (EM) between the Sm3+ ion was investigated both empirically and theoretically in the region of Sm3+ contents. Several theoretical-models were employed to simulate the lifetime of Sm3+ at various-concentrations, and the processes were investigated as a forced-electric dipole. The chemical-stability of CY0.95GB:0.05Sm3+ has also been investigated in this work. Interestingly, the CY0.95GB:0.05Sm3+ showed exceptional thermal-quenching resistance of>91.2% intensity at 400 K. The WLED containing CY0.95GB:0.05Sm3+ blended with the BAM:Eu2+ and CYAB:Tb3+ phosphor demonstrated low CCT ≈ 3843 K and high CRI ≈ 91.9. These findings were healthier than the industrial WLED having Y3Al5O12:Ce3+ and blue-LED.

Here we report a detailed investigation on the structural and superconducting properties of previously unreported CuIr2-xTixTe4 (0 ≤ x ≤ 0.2) samples. It is found that the charge density wave-like order is quickly suppressed with subtle Ti substitution on 5d Ir site in CuIr2Te4 and vanishes in all Ti-doped samples. Concurrently, superconducting critical temperature Tc is enhanced and increases up to 2.84 K at x = 0.075; thenceforth, Tc deceases with higher Ti-doped concentrations and forms a weak dome-shaped superconducting phase diagram. The optimal CuIr1.925Ti0.075Te4 composition exhibits type-Ⅱ superconductivity with its lower critical field (Hc1(0)) and upper critical field (Hc2(0)) based on Werthamer Helfand Hohenburg (WHH) model is 0.095 T and 0.212 T, respectively. The normalized specific heat jump ∆Cel./γTc = 1.34 is in good agreement with the nature of bulk superconductivity.

Here we report a new group of cobalt-free Cu-based dual-phase oxygen permeation membranes made up of Ce0.85Pr0.1Cu0.05O2-δ and PrxSr1-xFe1-yCuyO3-δ (x = 0.4, 0.6, y = 0.05, 0.1, 0.2). The structure, oxygen permeability and stability investigations are presented. Systematic studies reveal that the synergism of these two copper-based mixed ionic-electronic conducting (MIEC) oxides can reduce the sintering temperature and give rise to attractive oxygen permeability. We find the optimal 60 wt%Ce0.85Pr0.1Cu0.05O2-δ-40 wt%Pr0.4Sr0.6Fe0.95Cu0.05O3-δ composite displays the largest oxygen permeation flux with 1.60 mL min−1·cm−2 at 1000 °C under air/He gradient and retain a steady oxygen permeation flux for over 105 h. Moreover, the 60 wt%Ce0.85Pr0.1Cu0.05O2-δ-40 wt%Pr0.4Sr0.6Fe0.95Cu0.05O3-δ membrane yields an oxygen permeation flux of 0.98 mL min−1·cm−2 at 1000 °C under air/CO2 gradient and hold the close value over 65 h. Our findings are expected to promote further studies on new oxygen permeable composites and boost the possible applications in CO2 capture.

Bilayered YDy0.5Ba2Cu3.6O7−δ superconducting films with a thickness of about 1 μ were deposited by metallorganic deposition method, an interlayer of secondary phase of SrZrO3 (SZO) and BaZrO3 (BZO) were inserted. Detailed growth mechanism studies of these structures as well as superconducting properties in different temperatures and magnetic field range (0–5 T) were investigated. Structural analysis showed that bilayer structure changed clearly the growth mechanism of YBCO. The SZO interlayer smoothens the film surface. Magnetic measurements of superconducting properties demonstrated that the critical temperature decreases slightly when both of SZO and BZO interlayer were inserted. This indicates a growing strain effect at the layer interfaces. The critical current densities as well as pining forces of bilayered YDy0.5Ba2Cu3.6O7−δ in the entire applied temperature and magnetic field range were enhanced by the insertion of SZO layer and decreased when BZO layer is introduced. The enhancement of the pinning properties is explained by the dense flux pinning in layered YDyBCO superconductors; this result may give further improvements in the current-carrying capability.

Oxygenation is one of the most essential processes for practical applications of REBa 2 Cu 3 O 7−δ (RE123, RE = Y, Gd etc. rare earths) superconductors. Second generation high-T c superconducting coated conductors are based on biaxial textured RE123 thin films, on which, a cover layer of silver for protecting is normally applied. It results in a little more complicated oxygenation process compared to naked film without silver protective layer. In the present work, a series of absorbing oxygen post-annealing processes were carried out for YBa 2 Cu 3 O 7−δ coated conductors. The oxygen diffusion procedure and the kinetics in the annealing process were investigated. Analysis and calculations show that the activation energy was 1.01 eV, consistent with previous reports. Moreover, experiments show that the “over-doping” phenomena frequently occurs in coated conductors, and thus dropping the T c to as low as 86–88 K. To improve the temperature margin for practical applications (temperature difference between the superconducting transition temperature T c and application temperature), we investigated the potential of increase in T c by preventing from the “over-doped” happening, while keeping oxygen in order. Finally, by employing the new annealing process, we can produce long (several hundred meters) coated conductor with high T c,onset (92 K), narrow transition width and stable performance.

We report a systematic investigation on the evolution of the structural and physical properties, including the charge density wave (CDW) and superconductivity of the polycrystalline CuIr2Te4−x I x for 0.0 ≤ x ≤ 1.0. X-ray diffraction results indicate that both of a and c lattice parameters increase linearly when 0.0 ≤ x ≤ 1.0. The resistivity measurements indicate that the CDW is destabilized with slight x but reappears at x ≥ 0.9 with very high T CDW. Meanwhile, the superconducting transition temperature T c enhances as x increases and reaches a maximum value of around 2.95 K for the optimal composition CuIr2Te1.9I0.1 followed by a slight decrease with higher iodine doping content. The specific heat jump (ΔC/γT c) for the optimal composition CuIr2Te3.9I0.1 is approximately 1.46, which is close to the Bardeen–Cooper–Schrieffer value of 1.43, indicating that it is a bulk superconductor. The results of thermodynamic heat capacity measurements under different magnetic fields [C p(T, H)], magnetization M(T, H) and magneto-transport ρ(T, H) measurements further suggest that CuIr2Te4−x I x bulks are type-II superconductors. Finally, an electronic phase diagram for this CuIr2Te4−x I x system has been constructed. The present study provides a suitable material platform for further investigation of the interplay of the CDW and superconductivity.

A high critical current I c is crucial for the application of high temperature superconductors YBa 2 Cu 3 O 7 - δ in energy efficient power devices and wires. In this paper we report the fabrication of thick (YGd) 1.3 Ba 2 Cu 3 O 7−x films on a metal substrate using low-fluorine metal organic deposition method. The effects of the film thickness on the microstructure, texture and superconductivity properties of the films were evaluated. In order to increase the film thicknesses by single coating, the influence of withdrawal speed during the dip coating on resulting thickness are investigated with the other processing parameters fixed. It is revealed that there is a maximum thickness for a certain starting solution. Here we used 3 different solutions, Conventional Low Fluorine solutions with 2 M and 2.5 M, and super low-fluorine solution with 2.5 M. The maximum thicknesses of about 710 nm, 1280 nm and 1460 nm were obtained, respectively.

A new family of transition-metal monosilicides (MSi, M = Ti, Mn, Fe, Ru, Ni, Pd, Co, and Rh) electrocatalysts with superior electrocatalytic performance of hydrogen evolution is reported, based on the computational and experimental results. It is proposed that these MSi can be synthesized within several minutes by adopting the arc-melting method. The previously reported RuSi is not only fabricated more readily but eventually explored 8 MSi that can be good hydrogen evolution reaction catalysts. Silicides then can be another promising electrocatalysts family as carbides, wherein carbon has the same electronic configuration as silicon. All explored silicides electrodes exhibited low overpotentials (34-54 mV at 10 mA cm-2 ) with Tafel slopes from 23.6 to 32.3 mV dec-1 , which are comparable to that of the commercial 20 wt% Pt/C (37 mV, 26.1 mV dec-1 ). First-principles calculations demonstrated that the superior performance can be attributed to the high catalytic reactivity per site that can even function at high hydrogen coverages (≈100%) on multiple low surface energy facets. The work sheds light on a new class of electrocatalysts for hydrogen evolution, with earth-abundant and inexpensive silicon-based compounds.

Rational design and synthesis of low-cost noble-metal free electrode with high efficiency for hydrogen evolution reaction (HER) is crucial for the realization of eco-friendly hydrogen economy. Here, we report and design topologically nontrivial 1T’-MoTe2 single crystals as remarkable hydrogen evolution electrocatalyst. The catalytic 1T’-MoTe2 was controllably synthesized via solid-state reaction and then facilely exfoliated into nanosheets by isopropanol with the aid of sonication. The overpotentials at 10 mA cm−2( η 10) can reach 73 mV with a low Tafel slope of 46.3 mV dec−1, which are much lower than those reported by other preparation methods (η 10 > 300 mV, Tafel slope > 50 mV dec−1). The electrochemical impedance spectroscopy shows fast kinetics of 1T’-MoTe2 single crystal with low contact resistance of 0.3 Ω. Additionally, 1T’-MoTe2 single crystal also exhibits large electrochemical active surface area of 47.0 cm2, high turnover frequency of 1.02 s−1 at 0.4 V and excellent durability over 10 h in 0.5 M H2SO4( aq). This work reports 1T’-MoTe2 single crystal as an excellent candidate for HER, which makes it possible to fabricate other robust Te-derived HER electrocatalysts.

Developing good performance and low-cost oxygen permeable membranes for CO2 capture based on the oxy-fuel concept is greatly desirable but challenging. Despite tremendous efforts in exploring new CO2-stable dual-phase membranes, its presence is however still far from meeting the industrial requirements. Here we report a series of new Ca-containing CO2-resistant oxygen transporting membranes with composition 60wt.%Ce0.9Ln0.1O2-δ-40wt.%Ln0.6Ca0.4FeO3-δ (CLnO-LnCFO; Ln = La, Pr, Nd, Sm) synthesized via a Pechini one-pot method. Our results indicate all investigated compounds are composed of perovskite and fluorite phases, while the perovskite phases in the CNO-NCFO and CSO-SCFO membranes after sintering generates Ca-rich and Ca-less two kinds of grains with different morphologies, where the Ca-less small perovskite grains block the transport of oxygen ions and eventually result in poor oxygen permeability. Among our investigated CLnO-LnCFO membranes, CPO-PCFO exhibits the highest oxygen permeability and excellent CO2 stability, which were mainly associated with the improvement in crystal symmetry, non-negligible electronic conductivity of fluorite phase and the enhancement in electronic conductivity of perovskite. Our results establish Ca-containing oxides as candidate material platforms for membrane engineering devices that combine CO2 capture and oxygen separation.

Transition metal dichalcogenides (TMDCs) usually exhibit layered polytypic structures due to the weak interlayer coupling. 2H-NbSe2 is one of the most widely studied in the pristine TMDC family due to its high superconducting transition temperature (Tc = 7.3K) and the occurrence of a charge-density wave (CDW) order below 33 K. The coexistence of CDW with superconductivity poses an intriguing open question about the relationship between Fermi surface nesting and Cooper pairing. Past studies of this issue have mostly been focused on doping 2H-NbSe2 by 3d transition metals without significantly changing its crystal structure. Here we replaced the Se by Te in 2H-NbSe2 in order to design a new 1T polytype layered TMDC NbSeTe, which adopts a trigonal structure with space group P-3m1. We successfully grew large size and high-quality single crystals of 1T-NbSeTe via the vapor transport method using I2 as the transport agent. Temperature-dependent resistivity and specific heat data revealed a bulk Tc at 1.3 K, which is the first observation of superconductivity in pure 1T-NbSeTe phase. This compound enlarged the family of superconducting TMDCs and provides an opportunity to study the interplay between CDW and superconductivity in the trigonal structure., Comment: 21 pages, 6 figures, 2 tables

YBa 2 Cu 3 O 7-δ (YBCO) coated conductor has been a promising candidate for high-current transportation material in industry, while the critical current (I c ) becomes a limitation for large-scale application. An efficient way to improve I c is to increase the thickness of YBCO film without much reduction in critical current density (J c ). Metallorganic solution deposition (MOD) is a traditional method to fabricate YBCO films while it takes time as long as 10h during the pyrolysis process. In comparison, Low-Fluorine MOD (LF-MOD) method is applied to reduce the pyrolysis time to less than 2h. In this paper, we successfully obtain YBCO thick films up to 1.7μm by double dip coating process using low-fluorine MOD method. Though wrinkles are frequently observed on the surface of the first layer after pyrolysis at 400 °C for 0.5h, the surface of the final double coated YBCO thick film is homogeneous and cracks are hardly found. Further tests show relatively good c-axis orientation and J c value of about 10 5 A/cm 2 at 77K. With an optimization for the pyrolysis and crystallization processes, better superconducting properties of YBCO thick film are expected.