MATERIALS SCIENCE FORUM
·
2015
·
IF 0
Gang Chen,Chun Wei Gong,Chun Lin Fu,Xiao Dong Peng,Wei Cai,Rong Li Gao,Xiao Ling Deng
(Sr1-xBax) 2(Nb0.9Ta0.1) 2O7 (SBNT) ceramics were prepared by solid state reaction. The crystal structure of SBNT ceramics, surface morphology and dielectric properties were studied using XRD, SEM and LCR instrument analyzer, respectively. The results show that the grain size decreases with increasing Ba concentration, and all samples show single phase, no second phase can been observed. Addition of Ba ion can improve the dielectric properties of SBN ceramics. The dielectric constant increases first, then decreases; the maximum value (εr=97) can be obtained at x=0.1, the dielectric constant changes slightly with increasing wide frequency.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Jian Zhang,Penghui Yao,Xuanlin Lu,Jiaxuan Chen,Wen Liu,Yicheng Zhao,Yongdan Li
The sluggish oxygen reduction reaction (ORR) at the cathode is a key step in protonic ceramic fuel cells. In this work, Pr 1.7 Sr 0.3 Ni 0.7 Cu 0.3 O 4+δ cathode with a Ruddlesden-Popper (RP) structure is modified with the doping of Ba, and BaPrO 3-δ nanoparticles are formed on the surface of the cathode. The addition of Ba improves the oxygen vacancy concentration and the electrical conductivity of the cathode, and the cathode with the nominal composition of Pr 1.7 Ba 0.15 Sr 0.3 Ni 0.7 Cu 0.3 O 4+δ shows the highest activity for the ORR process. The cathode shows the lowest polarization resistance of 0.055 Ω cm 2 at 700 °C. The hydration ability of the cathode is also enhanced with Ba. The maximum power density of a protonic ceramic fuel cell with Pr 1.7 Sr 0.3 Ni 0.7 Cu 0.3 O 4+δ cathode increases from 877 to 1262 mW cm −2 at 700 °C after the doping of Ba in the cathode. The cell also shows a promising durability.
研究领域:
材料科学
·
能源工程
·
化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 35
·19930-19939
·
IF 3.049
Panqi Huang,Jingfei Luan
The effects of Ba-doping on the structure and photocatalytic performance of GaOOH were investigated for the first time in this paper. XRD, SEM, TEM, XPS, UPS, FT-IR, UV-Vis DRS, PL, BET and EPR characterizations were carried out to analyze the properties of Ba-doped GaOOH. The results showed that GaOOH crystallized well with the orthorhombic crystal system with space group Pbnm. The lattice parameters of GaOOH were found to be a = 4.509526 Å, b = 9.771034 Å and c = 2.969284 Å. The transition in the structural morphology of GaOOH before and after Ba-doping was observed in SEM pictures in which the morphology of GaOOH varied from wood-like to rice husk-like. At the same time, the specific surface area of 4 wt% Ba-doped GaOOH (21.5854 m2 g−1) was 3.42 times that of pure GaOOH (6.3047 m2 g−1). Ba-doping caused a red shift of the band gap according to UV-Vis DRS results. The enhanced defect states caused by Ba-doping was confirmed by PL results, which decreased the recombination rate of photogenerated electrons and photogenerated holes. Compared with pure GaOOH, when GaOOH with different Ba content was used as photocatalyst, the removal rate of enrofloxacin was increased by more than 20% only by illumination for 60 min. In addition, Ba-doped GaOOH had excellent stability and could be reused, which could reduce costs and increase the potential of its practical application.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Research
·
2021
·Vol. 15
·期 4
·3264-3272
·
IF 8.897
Cai Changkun,Xie Manyi,Xue Ke,Shi Yu,Li Shuting,Liu Yuanyuan,An Shengli,Yang Hong
La 06 Sr 04 Co 02 Fe 08 O 3− δ (LSCF) is recognized as one of the most promising cathode materials for the highly-desired intermediate-temperature solid oxide fuel cell (IT-SOFC) technology. However, it is still challenged by polarization losses due to reduced operation temperatures. In this work, a series of Ba 2+ -doped La 0.6− x Ba x Sr 0.4 Co 0.2 Fe 0.8 O 3− δ (LBSCF x, x = 0.05, 0.10, 0.15, and 0.20) materials are successfully synthesized and their electrochemical performances are evaluated as a cathode for IT-SOFC technology. The study shows that, compared to the un-doped LSCF, the Ba 2+ -doped LBSCF possess higher electrical conductivities at 500–800 °C and display lower polarization resistances to oxygen adsorption/dissociation. As a result, the Ni-SDC|SDC|LBSCF0.20 cell (SDC = samarium-doped cerium, Sm 0.2 Ce 0.8 O 1.9 ) delivers a high maximum power density of 0.704 W/cm 2 at 750 °C, which is > 30% higher than the Ni-SDC|SDC|LSCF cell. This work reveals that Ba 2+ -doping is effective in enhancing oxygen catalytic activity of LSCF-based cathode materials, demonstrating a new and commercial-feasible strategy in developing high performance cathode materials for the IT-SOFC technology.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2024
·Vol. 53
·期 42
·17200-17206
·
IF 3.5
Wang Zhao,Jiazheng Zhou,Linan Wang,Wenqi Jin,Yingying Kong,Yu Chu,Junjie Li
Pb-based chalcogenides display abundant structural diversity and distinguished properties. Based on a mixed anion and dimensional reduction combined strategy, a wide band gap Pb-based thiohalide, Pb6Ba3Si2S8I10, has been rationally designed and synthesized experimentally by the flux method. The compound crystallizes in the Rc space group with cell parameters a = 9.7925(2) Å, b = 9.7925(2) Å, and c = 70.628(3) Å and is composed of [SiS4] tetrahedra and unprecedented [PbI5S2] polyhedral units, resulting in a unique quasi-two-dimensional structure, which enriches the chemical and structural diversity of Pb-based thiohalides. The experimental band gap of Pb6Ba3Si2S8I10 was determined to be 2.80 eV. Based on statistical analyses and to the best of our knowledge, it is the largest experimental optical band gap among the known Pb-based thiohalides. The results demonstrate the feasibility of using highly electropositive Ba atoms to regulate the dimensions of the structural framework of thiohalides and give new insights into the structure and property modifications of thiohalides by the mixed anion and dimensional reduction combined strategy.
研究领域:
无机化学
·
材料科学
·
固体化学
·
功能材料
·
半导体物理
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2016
·Vol. 18
·期 28
·19165-19172
·
IF 4.449
Lihong Bao,Xiaoping Qi,Tana,Lumen Chao,O. Tegus
Multiple nanocrystalline rare-earth hexaborides La1−xBaxB6 have been synthesized via a single step solid-state reaction. The Ba doping effects on crystal structure, grain morphology, magnetic and optical absorption properties were investigated using XRD, FESEM, HRTEM, SQUID magnetometry and optical measurements. The results show that all the Ba-doped hexaborides crystallize in the CsCl-type single phase, indicating the Ba atoms occupied the lattice sites of LaB6. The optical absorption results indicate that the absorption valleys of LaB6 are red-shifted from 622 nm to 780 nm when the Ba doping content increases to x = 0.8. The first-principle calculation results reveal that Ba doping reduces the total kinetic energy of the electrons of LaB6, which lead to the absorption valleys moving toward a higher wavelength. Meanwhile, the band gap of BaB6 obtained from optical absorption is in good agreement with the theoretical calculation results. The magnetic measurements results showed that Ba doping lead to room-temperature ferromagnetism of LaB6 due to the different ionic radii of La3+ and Ba2+ causing intrinsic crystal defects, which is directly observed experimentally by HRTEM. This is the first time that we have found the tunable optical and ferromagnetic behavior of Ba doped nanocrystalline LaB6. Thus, nanocrystalline La1−xBaxB6, as multi-functional materials, should open up a new route to extend the optical and magnetic applications of LaB6 nanopowder.
研究领域:
材料科学
·
凝聚态物理
·
纳米材料
·
功能材料
·
磁学
·
光学材料
✓ 已验证
DOI
高影响因子
SOLID STATE IONICS
·
2017
·
IF 2.354
Yan Sun,Wenning Yan,Li An,Bingbin Wu,Kaifu Zhong,Ruizhi Yang
A super solid electrolyte of Ba-substituted Li 10 GeP 2 S 12 is designed and fabricated to achieve high electrochemical stability. Among the Ba-substituted Li 10 GeP 2 S 12 solid electrolytes, the composition of Li 9.4 Ba 0.3 GeP 2 S 12 exhibits the highest ionic conductivity of 7.04 × 10 − 4 S cm − 1 with an activation energy of 28.27 kJ mol − 1 at 25 °C. The electrochemical window of Li 9.4 Ba 0.3 GeP 2 S 12 is between 0 and 6 V (vs. Li), which is higher than the typical 5 V window of Li 10 GeP 2 S 12 . As compared with Li 10 GeP 2 S 12 , Li 9.4 Ba 0.3 GeP 2 S 12 demonstrates a significantly reduced polarization and a better cycle stability though its ionic conductivity is slightly lower than that of the former. The electrochemical stability of Ba-substituted Li 10 GeP 2 S 12 can be attributed to the structural stability resulting from the stable interaction between Ba 2 + and S 2 − in the structure.
研究领域:
材料科学
·
固态离子学
·
电化学
·
能源材料
·
无机固体化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Faxiang Lu,Xiumin Xu,Yang Cao,Xingfu Zhou
The electron transport layer (ETL) plays an important part in perovskite solar cell (PSC) devices. TiO 2 nanorod arrays (TiO 2 NAs) is widely used as ETL for perovskite solar cells because of its excellent energy level matching. Furthermore, TiO 2 NAs provide the directed 1-D electron transmission channel. In this work, rutile TiO 2 NAs synthesized by one-step hydrothermal method were used as the ETL of carbon-based perovskite solar cells to improve the performance. The interface between the ETL and perovskite was modified by barium acetate to reduce interface defects, non-radiative recombination and improve the electron transport rate. The perovskite film based on the Ba@TiO 2 NAs exhibited larger grains and fewer grain boundaries, which was of positive significance for improving the power conversion efficiency (PCE) of devices. At the same time, we replaced the precious metal electrode and unstable organic hole transport layer (HTL) with carbon electrode, which reduces the manufacturing cost and improves the stability of the device. Finally, all inorganic HTL-free carbon-based perovskite solar cells based on Ba@TiO 2 NAs showed a champion PCE of 10.74%, which is 14.74% higher than the control device.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）