INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2022
·Vol. 47
·期 79
·33861-33871
·
IF 7.139
Zhizhong Leng,Zuzhi Huang,Xu Zhou,Bo Zhang,Hu Bai,Juan Zhou,Shaorong Wang
Proton-conducting solid oxide electrolysis cells (H-SOECs) are attracting attentions of researchers due to their unique advantages. The proton-conducting material BaCe 0·7 Zr 0·1 Y 0.1 Yb 0.1 O 3-δ (BZCYYb) has both the advantages of barium ceria-based and barium zirconate-based materials. BZCYYb material usually is synthesized by solid-state reaction (SSR) method, hence the densification of this electrolyte material is the key to restrict the application of H-SOECs. In this paper, effects of adding 1 wt% of different sintering aids (NiO, CuO, ZnO) to BZCYYb on the grain size and the conductivity are investigated. After adding 1 wt% of NiO and CuO sintering aids, BZCYYb electrolyte achieves ideal density. The electrical conductivity of four samples (BZCYYb without adding sintering aid, BZCYYb with 1 wt% NiO, CuO, ZnO, respectively) is tested under different steam concentrations of air, nitrogen, hydrogen, and nitrogen-hydrogen mixture. The conductivity increased after the sintering aid is added. With the increase of steam concentration, the conductivity decreased slightly and then increased due to electron holes under oxygen atmosphere with steam at high temperature. In other atmospheres, the conductivity increases with the steam concentration. In the atmosphere of 20 vol% H 2 O-Air and H 2 , the conductivity of the BZCYYb samples with 1 wt% CuO is about 1.087 × 10 −2 S cm −1 and 9.02 × 10 −3 S cm −1 at 650 °C, and the conductivity of the BZCYYb samples with 1 wt% NiO is 1.277 × 10 −2 S cm −1 and 8.24 × 10 −3 S cm −1 , respectively. However, compared with NiO, CuO has advantages in promoting hydration reaction and proton conduction of BZCYYb electrolyte.
研究领域:
材料科学
·
电化学
·
能源材料
·
固态离子学
·
陶瓷材料
✓ 已验证
DOI
高影响因子
SOLID STATE SCIENCES
·
2024
·
IF 3.4
Kaiwu Fu,Dandan Ma,Nan Zhang,Jiacheng Cao,Xiaonan Chen,Min Zhu,Peiqing La
Oxide thermoelectric materials have a wide range of applications due to their excellent stability, low cost, and non-toxic properties. However, their low thermoelectric conversion efficiency limits their practical use. Therefore, improving the performance of oxide thermoelectric materials has become the focus of current research. Interface engineering is an important approach to enhance thermoelectric properties by optimizing electrical transport properties through multiphase composite regulation of phase interface structure. A series of Sr 0.6 La 0.4 Nb 2 O 6-δ /x wt% graphite (x = 0, 0.6, 1.0, 1.5, 2.0) composite ceramics thermoelectric materials were prepared, and the mechanism for improving their thermoelectric properties was explored. Graphite serves as an electron momentum amplifier within the Sr 0.6 Ba 0.4 Nb 2 O 6-δ matrix, thereby augmenting both conductivity and power factor values significantly. Notably, the incorporation of 1.5 wt% graphite led to a remarkable enhancement in the thermoelectric power factor at 1073 K, reaching an impressive value of 254.84 μW/K 2 m - representing a notable increase of approximately 51 % compared to the unmodified sample - primarily attributed to the elevated electrical conductivity .
研究领域:
材料科学
·
无机非金属材料
·
热电转换
·
固态物理
·
功能陶瓷
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·Vol. 49
·期 14
·23538-23545
·
IF 5.2
Jianbo Zhu,Jing Lin,Chao Yu,Yi Fang,Zhenya Liu,Zhonglu Guo,Chengchun Tang,Yang Huang
Boron nitride (BN) aerogels is a class of three-dimensional (3D) hierarchical network structure assembled from BN micro/nanostructures. The construction of BN/BN composite aerogel by introducing of BN micro/nano-structural units into the 3D BN aerogel scaffold provides an effective strategy for obtaining BN aerogel with improved all-round properties. Here, a novel kind of BN/BN composite aerogels has been developed by vacuum impregnation of ammonia borane (AB) into fiber-based BN aerogels, followed by high-temperature pyrolysis . The introducing of AB into BN aerogels makes the formation of unique AB/BN composite aerogels, and the high-temperature decomposition of AB results in the obtaining of a series of multifunctional composites, i.e. BN/BN composite aerogels. As compared with the porous BN microfibers in original BN aerogel, the self-assembled fibers in BN/BN composite aerogel are densely covered with high crystalline BN nanoflakes, which are generated by the AB decomposition. The obtained BN/BN composite aerogels have shown excellent thermal stability, significantly improved hydrophobic effect and heat transfer capability. This work provides a new idea for the future research and development of BN composite aerogels.
研究领域:
材料科学
·
纳米材料
·
热功能材料
·
多孔材料
·
复合材料
✓ 已验证
DOI
高影响因子
POLYMER
·
2019
·
IF 3.771
Wenbo Shen,Ling Wang,Gang Chen,Chunxin Li,Lanying Zhang,Zhou Yang,Huai Yang
A liquid crystalline epoxide was synthesized and its curing reactivity was compared with that of the conventional epoxy monomers . By utilizing the difference in curing reactivity between the liquid crystalline epoxide and non-liquid crystalline epoxy monomers, a coexistent system of polymer-dispersed and polymer-stabilized liquid crystal (LC) in the intelligent films can be obtained by two-step thermal curing method. If the later curing process was undertaken under an external electric field , the ordered microstructure of liquid crystalline epoxy polymer (LCEP) network can be implanted into the conventional epoxy resin. The competition of the anchoring effect on the LC molecules from the LCEP network and the conventional epoxy resin matrix was crucial to the electro-optical performance of the films. Moreover, the performance of the films can be adjusted by controlling the content of liquid crystalline epoxide and the external electric field applied during later curing. This approach can provide a facile route to regulate the electric-optical performance of polymer-dispersed liquid crystal films for practical applications.
研究领域:
材料科学
·
高分子化学
·
功能材料
·
光电工程
·
智能材料
✓ 已验证
DOI
高影响因子
Small
·
2021
·Vol. 18
·期 8
·2105599
·
IF 13.281
Wuhong Xue,Qitao Jiang,Fakun Wang,Ri He,Ruixue Pang,Huali Yang,Peng Wang,Ruilong Yang,Zhicheng Zhong,Tianyou Zhai,Xiaohong Xu
2D ferroelectrics with robust polar order in the atomic-scale thickness at room temperature are needed to miniaturize ferroelectric devices and tackle challenges imposed by traditional ferroelectrics. These materials usually have polar point group structure regarding as a prerequisite of ferroelectricity. Yet, to introduce polar structure into otherwise nonpolar 2D materials for producing ferroelectricity remains a challenge. Here, by combining first-principles calculations and experimental studies, it is reported that the native Ga vacancy-defects located in the asymmetrical sites in cubic defective semiconductor α‑Ga 2 Se 3 can induce polar structure. Meanwhile, the induced polarization can be switched in a moderate energy barrier. The switched polarization is observed in 2D α‑Ga 2 Se 3 nanoflakes of ≈4 nm with a high switching temperature up to 450 K. Such polarization switching could arise from the displacement of Ga vacancy between neighboring asymmetrical sites by applying an electric field. This work removes the point group limit for ferroelectricity, expanding the range of 2D ferroelectrics into the native defective semiconductors.
研究领域:
材料科学
·
凝聚态物理
·
纳米电子学
·
功能材料
·
半导体物理
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
·
IF 3.014
Dong Zhang,Xuanxuan Ma,Qi Zhang,Yanru Xie,Qiang Shi,Qiangru Wang,Wenjun Wang
Zn x Al 2 O 4 :Cr 3+ (0.8 ≤ x ≤ 4) phosphors with spinel structure were prepared by using sol-gel method. The structure, morphology and photoluminescence properties were analyzed by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron paramagnetic resonance (EPR) and photoluminescence (PL). The spinel structure of ZnAl 2 O 4 was formed for all samples, and hexagonal structure of ZnO appeared in the powders with x ≥ 1.1. The results of XRD, SEM and TEM showed that the crystallinity of Zn x Al 2 O 4 :Cr 3+ phosphors was improved with increasing the value of x . The PL spectra showed a series of sharp emission peaks ranging from 650 nm to 730 nm assigned to spin-forbidden 2 E g → 4 A 2 g transition of Cr 3+ ions in spinel lattices. The most intense emission was observed in Zn 1.2 Al 2 O 4 :Cr 3+ powders, and the results of EPR showed that this enhancement resulted from the best dispersity of Cr 3+ ions in Zn x Al 2 O 4 lattices.
研究领域:
材料科学
·
无机化学
·
固体物理
·
发光材料
·
纳米材料
✓ 已验证
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2021
·
IF 9.127
Fengchen Zhou,Xu-Sheng Yang,Jiangwen Liu,Jun Liu,Renzong Hu,Liuzhang Ouyang,Min Zhu
Owing to the high theoretic capacity (2596 mAh g −1 ) and suitable lithiation potential (～0.7 V vs. Li + /Li), Black phosphorus (BP) is considered as an ideal anode material for the fast-charging lithium-ion batteries. However, BP still faces the large volume change and low Li + transfer during the charge/discharge. In this work, a facile two-step high-energy ball milling method is developed to synthesis the black phosphorus@TiP 2 –C (CBP@TiP 2 –C) nanocomposite for the high-rate performance anode material, in which the conductive nanocrystalline TiP 2 is in-situ introduced and uniformly distributed into BP-C matrix. We reveal that the uniformly dispersed TiP 2 nanocrystals can enhance the electronic and ionic conductivities of active particles and the electrode reaction kinetics. The lithiation product cubic Li y TiP 4 phase is beneficial to release the stress, reduce the Li + diffusion energy barrier and accelerate the Li + extraction from LiP 3 upon delithiation . Moreover, the contact among different components can be improved by Ti–C and P–C bonds in the CBP@TiP 2 –C, thus ensuring excellent electric contact within the material and enhancing the structural stability of composites. As a result, the CBP@TiP 2 –C anode displays a high reversible capacity of 1007.4 mAh g −1 at 10.0 A g −1 and excellent capacity retention of 925.6 mAh g −1 after 500 cycles at 2 A g −1 .
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
固态化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2022
·
IF 7.392
Baifeng Wu,Xiaofeng Wang,Xuefeng Xia,Qixin Wan,Yangsheng Li,Fan Li
The power conversion efficiency (PCE) of the perovskite solar cell (PSC) has made an illustrious breakthrough in the past ten years. However, it is still a great challenge to fabricate high-quality perovskite films due to the intrinsic high defect-density and internal non-radiative recombination, which has severely hindered the development of PSCs . Herein, a new-type additive guanidinium tetrafluoroborate (GuaBF 4 ) is introduced to improve the perovskite films quality, thus boosting photovoltaic performance of resultant PSCs . It is demonstrated that owing to the synergistic effect of Gua + and BF 4 − , the introduction of GuaBF 4 can improve the quality of CH 3 NH 3 PbI 3 (MAPbI 3 ) films. Through optimizing the concentration of GuaBF 4 , the MAPbI 3 film with GuaBF 4 displays higher crystallinity , enlarged crystal grain and smoother surface. Furthermore, by virtue of the strong interaction between MAPbI 3 and GuaBF 4 , the inclusion of GuaBF 4 can effectively passivate traps/defects in perovskite films, thereby diminishing the non-radiative recombination and promoting the charge carrier transportation. Consequently, a high-performance MAPbI 3 PSC with a PCE of 20.62 %, lessened hysteresis behavior and improved moisture stability is achieved. Our research emphasizes on the significance of the synergistic effect in additives for high-performance PSCs.
研究领域:
材料科学
·
能源科学
·
半导体器件
·
表面化学
·
光电子学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 48
·期 6
·8579-8588
·
IF 4.527
Sunyi Shen,Shaolei Song,Jinming Wang,Rong Li,Xingchao Li,Qiang Zhen
Microstructure control and multiple compounding methods in the synthesis stage can enhance microwave absorption performance of microwave absorbents. In this work, we successfully synthesized binary TiB 2 –SiC (TsBC) powders with hexagonal sheet (TiB 2 ) and particle (SiC) interlocking structures by sol-gel carbothermal reduction method. We investigated the effect of raw material ratio and synthesis temperature on the synthesized powders and evaluated the microwave absorption properties of the synthesized TsBC powders. It was found that the TsBC absorber exhibited excellent microwave adsorption properties with the minimum Reflection Loss ( R L ) reached −21.8 dB at 17.4 GHz corresponding to the thickness of 4 mm. This excellent performance was attributed to the interfacial polarization between TiB 2 –SiC interfaces and the multiple reflections between the sheet-particle interlocking structures.
研究领域:
材料科学
·
功能材料
·
复合材料
·
电磁学
·
无机非金属材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Luquan Ren,Wangxuan Li,Zhenguo Wang,Xueli Zhou,Chao Xu,Yulin He,Zhengyi Song,Qingping Liu
Spruce branches have a continuous gradient in the microfibril angle of helically entwined cellulose fibrils in their internal cell walls, which confers the modulation of the site-specific mechanical properties. This paper draws inspiration from the microstructure within spruce branches and successfully fabricates a biomimetic structural material assembled from stiff and soft resins in a double-helix distribution using rotational co-extrusion 3D printing . The tunability of the mechanical properties of the helical structural material can be achieved by regulating the helical degree and ratio of two resins in the extrusion filament in real-time. Additionally, a strategy for controlling failure is proposed through dynamic programming of the local structure within the printed sample. Furthermore, compared with the homogeneous beam, the prepared spruce-like beam can effectively mitigate stress concentration during the loading process, achieving greater deformation capacity. This helical structural material is expected to meet customized mechanical performance requirements and enrich the bionic structural material system.
研究领域:
材料科学
·
生物医学工程
·
仿生学
·
高分子材料
·
力学性能优化
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2017
·Vol. 52
·期 19
·11569-11579
·
IF 2.599
Lan Jin-Le,Ma Wenqiang,Deng Chengjie,Ren Guang-Kun,Lin Yuan-Hua,Yang Xiaoping
A series of K-doped Bi 1− x
K
x
CuSeO (0 ≤ x ≤ 0.10) compounds were prepared by combustion synthesis combined with spark plasma sintering method. Phase composition and microstructure analysis indicate almost single BiCuSeO phase in low doping level, while phase separation appears in heavy doping level. The thermoelectric properties of the Bi 1− x
K
x
CuSeO compounds have been measured in the temperature range of 323–823 K. The electrical conductivity is greatly enhanced by almost three times from 8.70 to 26.2 S/cm at 323 K by the substitution of Bi with K due to the large decrease of the activation energy. The overall thermal conductivity decreases significantly due to the strong point defect scattering by K doping and possibly enhanced interface scattering on the secondary phase. The maximum ZT reaches 0.6 at 823 K for the sample of x = 0.02, which is about 50% higher than that of the pristine sample. Our work offers a fast and more efficient approach for the fabrication of BiCuSeO-based materials.
研究领域:
材料科学
·
无机非金属材料
·
热电材料
·
固态化学
·
纳米复合材料
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Liang Zheng,Wenjie Zhang,Qi Wang,Hong Zhang,Zhou Yu,Cuihua Cheng,Yong Zhang,Ming Lei,Yong Zhao
MgB 2 bulks with NaCl doping amount ranging from 0–30 at% have been prepared by hot pressed sintering process . With the increase of NaCl doping amount, the c axis lattice parameter of MgB 2 monotonously increases, indicating the substitution of Mg atoms by larger Na atoms. Meanwhile, the intensity of diffraction peaks of both NaCl and impurity phase of MgO increases. More compact morphology was found in the NaCl doped MgB 2 samples. The critical transition temperature ( T c ) decreases from 38.2 K to 36.8 K with the increase of NaCl doping amount from 0 to 30 at%, and the corresponding transition width of T c (Δ T c ) increases from 0.5 K to 1.8 K. When the doping amount of NaCl is not exceeding 10 at%, the J c value is about 10 6 A/cm 2 at 4.2 K, 3 T, and 5 × 10 5 A/cm 2 at 10 K, 3T. J c performance of the 5 at% NaCl doped MgB 2 sample (NC05) reaches 6.8 × 10 5 A/cm 2 at 20 K, 2T, which improves approximately 20% compared to the pure one, attributing to the better grain connectivity of MgB 2 and enhancement of flux pinning force by NaCl doping.
研究领域:
凝聚态物理
·
材料科学
·
超导材料
·
无机固体化学
·
功能陶瓷
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）