Energy Technology
·
2019
·Vol. 7
·期 9
·1900374
·
IF 3.163
Zhong Ma,Dewang Zeng,Shuai Zhang,Rui Xiao
NiFe 2 O 4 oxygen carrier (OC) presents higher oxygen carrying capacity than single metal oxides (NiO and Fe 2 O 3 ). However, the redox ability of NiFe 2 O 4 gets deactivated due to phase segregation. Herein, the investigation of the effect of supports (CeO 2 , CeZrO 2 , and ZrO 2 ) on the phase stability and the redox performance of NiFe 2 O 4 during the chemical looping (CL) process are presented. The structure of NiFe 2 O 4 -based OCs is characterized using different characterization methods. The CL reaction is conducted in a fixed-bed reactor at 900 °C under alternate 5% CO/N 2 and 5% O 2 /N 2 atmospheres. The results indicate that the redox performance and the phase stability of NiFe 2 O 4 -based OCs are significantly affected by the supports. According to experimental results, CeO 2 can improve the oxygen mobility of NiFe 2 O 4 . The CeO 2 –NiFe 2 O 4 OC has the best performance in terms of both recyclability and phase stability during the redox cycles. The results show that CeO 2 –NiFe 2 O 4 can reduce the tendency of Fe segregation due to the high concentration of oxygen vacancies. It can be reduced and reoxidized to the original crystalline phase of NiFe 2 O 4 . Nevertheless, the CeZrO 2 –NiFe 2 O 4 and ZrO 2 –NiFe 2 O 4 OCs have drawbacks related to serious sintering and phase segregation into Fe 2 O 3 .
研究领域:
材料科学
·
化学工程
·
能源化学
·
催化化学
·
无机化学
✓ 已验证
DOI
高影响因子
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
·
2024
·Vol. 130
·期 3
·203
·
IF 2.5
Xu Yingying,Xia Siyi,Zhang Yingjiu,Song Hongzhang,Liu Shaohui,Hao Haoshan
In this study, ceramic samples of Bi 2 Sr 2 Co 2 O y + v wt% B 2 O 3 ( v = 0.0, 0.1, 0.2, 0.3, 0.4) were synthesized using the solid state reaction method, and the influence of B 2 O 3 additive on their microstructure and thermoelectric properties were investigated. On one hand, the B 2 O 3 additive acted as a sintering aid, enhancing carrier mobility. On the other hand, B 2 O 3 dispersion served as a nano-second-phase, increasing hetero-interfaces and strengthen phonon scattering, thereby effectively suppressing lattice thermal conductivity. By dual optimization of both electric and thermal transport performance, the Bi 2 Sr 2 Co 2 O y + 0.3 wt% B 2 O 3 sample achieved a high ZT value (thermoelectric figure of merit) of 0.31 at 923 K, which was improved by approximately 33% compared with the pristine Bi 2 Sr 2 Co 2 O y sample.
研究领域:
材料科学
·
凝聚态物理
·
无机非金属材料
·
热电材料
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2023
·Vol. 11
·期 43
·23319-23329
·
IF 11.9
Bang-Zhou Tian,Yi-Yan Liao,Fang Xu,Xiao-Ling Qiu,Fu-Jie Zhang,Ran Ang
Interfacial modulation has been considered an effective strategy to enhance the thermoelectric (TE) performance by decoupling thermal and electrical parameters. However, inappropriate interfacial heterojunctions can significantly deteriorate electrical transport while enhancing phonon scattering, which causes no substantial improvement in TE performance. Herein, we introduce two-dimensional graphene or MXene into the Mg3.2Sb0.5Bi1.49Te0.01 matrix by ball mixing combined with rapid sintering to modify the composition and structure at the interface. The differences in morphology, size and distribution of interfacial graphene and MXene lead to distinct results which show that incorporated graphene flakes with larger size hinder the carrier transport, while the homogeneously dispersed tiny MXene provides improved carrier channels and boosts the mobility. On the other hand, such uniformly diffused heterogeneous MXene structures create stronger scattering on phonons compared to enriched graphene phases, resulting in a low lattice thermal conductivity of ∼0.66 W m−1 K−1 and enhanced zT of ∼1.0 at 513 K in Mg3.2Sb0.5Bi1.49Te0.01-0.6 wt% MXene with good component stability in air. This work highlights the importance of size, concentration, and distribution in the interfacial modulation strategy, demonstrating an effective method for developing high TE performance Mg3(Sb, Bi)2-based near-room-temperature materials.
研究领域:
材料科学
·
凝聚态物理
·
纳米材料
·
能源材料
·
固体化学
✓ 已验证
DOI
高影响因子
FUEL
·
2024
·
IF 6.7
Xingyan Liu,Tianrong Xiong,Yonggang Xu,Kunhe Yang,Youzhou He,Haifeng Yang,Hong Wu,Jiajia Jing,Siqi Li,Siping Wei
Defect engineering for MOFs is a promising approach to accelerate the charge transfer to further enhance the photocatalytic performance. Up to now, the current defect engineering strategy for MOFs mainly focuses on a single adjustment mode with the apparent ceiling effect, whether the further break out of the ceiling effect could be achieved through the combination of two or more adjustment modes is still in its infancy. In this work, the original NH 2 -MIL-125 was firstly adjusted by a single adjustment mode in ethanol solvothermal method to obtain partially linker defective NM-125-X (where X signifies the distinct temperatures used in the solvothermal treatment, with optimal results observed at X = 120). Subsequently, the NM-125-120 was further re-regulated by adjusting the ligand defects through another adjustment mode in water heating agitation, resulting in the ultimate defective NM-125-120-65. The NM-125-120-65 obtained through double defect engineering avenue showed superior photocatalytic performance with the hydrogen production rate of 11585.23 μmol·g −1 , which was 1.23 and 14.05 times as those of partially defective NM-125-120 (9427.65 μmol·g −1 ) and original NH 2 -MIL-125 (824.85 μmol·g −1 ), respectively. In addition, the NO removal rate of NM-125-120-65 was 64.8 % also higher than that of NM-125-120 (37.8 %) and NH 2 -MIL-125 (23.6 %). Through a series of comparative experiments, especially TGA and XPS, it was noted that the ligand defective NH 2 -MIL-125 can be formed by ethanol solvothermal method, and it was also confirmed that through further re-regulating the ligand defects in water heating agitation, the linker defects could also be further expanded. The PL emission spectra, IT diagrams, and EIS measurements displayed that the NM-125-120-65 had outstanding conductivity and excellent electron mobility compared to NM-125-120 and NH 2 -MIL-125. This work provided a novel approach for the subsequent defect engineering by another adjustment mode based on the existing defective MOFs via double linker defect engineering adjustment modes, so as to further obtain better photocatalytic performance for solving the environmental and energy crisis.
研究领域:
材料科学
·
环境化学
·
能源化学
·
光催化
·
纳米材料
·
物理化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 100
·97783-97790
·
IF 3.289
Ying Sun,Qizan Huang,Xueqin Zhang,Xiaojing Ding,Pei Han,Baoping Lin,Hong Yang,Lingxiang Guo
In recent years, side chain engineering has been proven to play a critical role in the development of high performance conjugated polymers for organic electronics. Here, we report a new strategy to improve charge transport property through side chain functionalization. A series of carbazole–diketopyrrolopyrrole based conjugated polymers P1, P2 and P3 with different side chains have been designed and synthesized. For P2 and P3, a pyrene and carbazole unit were incorporated into the terminal of the alkyl side chain, respectively. Thermal properties, crystallinities, UV-vis absorptions, electrochemical properties as well as charge transport properties of the polymers were investigated in detail. Interestingly, results showed that incorporation of the fused aromatic ring into the side chain terminal not only changed the absorption and electrochemical properties, but also affected the charge transport properties. The pyrene and carbazole group in the side chain terminal significantly promoted aggregation of the polymer chains, which would provide short-range order for improved charge carrier mobility. Compared to the hole mobility (0.019 cm2 V−1 s−1) for polymer P1 with the whole alkyl chains, increased hole mobilities of 0.081 cm2 V−1 s−1 and 0.052 cm2 V−1 s−1 were achieved for polymer P2 and polymer P3, respectively. It is worthy to note that our strategy gives rise to no increment of the crystallinity of the polymer, being beneficial for the practical application of soft electronics since high crystallinity of the material usually leads to poor thin film uniformity and weak mechanical resilience. In this respect, we offer a promising tool to aid rational polymer design for enhanced charge transport property.
研究领域:
高分子化学
·
有机电子学
·
材料科学
·
半导体材料
·
光电功能材料
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Yuqing Sun,Adeel Abbas,Hongxiang Wang,Chang Tan,Zhihao Li,Yujie Zong,Hui Sun,Chunlei Wang,Hongchao Wang
Quaternary Cu 2 MnSnSe 4 alloys with low intrinsic thermal conductivity are identified as promising middle-temperature thermoelectric materials. However, zT is depressed by the poor electrical performance. To overcome this issue, here, a series of Cu 2.1 Mn 0.9 SnSe 4 samples are prepared by ball-milling method which appears as a time-saving technique and lattice strain variation is observed by changing the annealing time ( x = 0, 1, 2, 3, 4 days). The vacancy defects concentration of Cu, with lowest vacancy defects formation energy, is changed with the competition between compression and tension-strain state, consistent with the first principles calculations, which optimizes the carrier transport. As a result, about 4 times increment of the carrier mobility is found. Moreover, the lattice strain of several nanometers is observed with TEM analysis, which scatters phonon strongly. A lowest κ L value of 0.57 W m −1 K −1 at 673 K is obtained for x = 3 sample, which is close to the amorphous limit. The interactive effect of enhanced mobility and strong scattering of phonons, contributing to a record zT ∼ 0.48 at 673 K for x = 3 sample. Lattice strain engineering is an effective tactic to simultaneously optimize the electrical and thermal transport.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
能源材料
·
半导体物理
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry A
·
2024
·Vol. 12
·期 15
·8893-8899
·
IF 10.7
Ziming Zhang,Zhiqiang Gao,Tingting Deng,Qingfeng Song,Lidong Chen,Shengqiang Bai
Mg3(Sb,Bi)2-based Zintl compounds have attracted lots of attention due to their high thermoelectric performance and good mechanical properties. However, thermally activated mobility, which is ascribed to the grain boundary scattering, greatly limits their practical use. In this work, we reveal the plasticity of Mg3(Sb,Bi)2-based compounds in the compressive strength test. The ab initio analysis indicates that this plasticity should be ascribed to the low slip barrier energy (∼580 mJ m−2), which is only one third of the cleavage energy (∼1600 mJ m−2). Based on this finding, we propose a cold-deformation procedure to elongate particles and to enhance texture, which successfully suppresses the grain boundary scattering. As a result, a high carrier mobility of 86.6 cm2 V−1 s−1 and a high power factor of 16.2 μW cm−1 K−2 in Mg3.1Bi1.5Sb0.49Te0.01 are obtained at room temperature. The plastic deformation capacity of Mg3(Sb,Bi)2 compounds provides a near-net-forming method to fabricate special-shaped devices at room-temperature, which will extend the application fields of thermoelectric techniques.
研究领域:
材料科学
·
凝聚态物理
·
无机非金属材料
·
热电转换
·
固态物理化学
✓ 已验证
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 45
·2403852
·
IF 13
Xinxin Wang,Chao Wang,Yajing Wang,Min Hao,Shengqiang Cui,Xudong Huang,Chunhui Wang,Jing Chen,Zhenxiang Cheng,Jianli Wang
N-type PbSe thermoelectric materials encounter challenges in improving the power factor due to the single-band structure near the Fermi level, which obstructs typical band convergence. The primary strategy for enhancing the thermoelectric figure of merit (ZT) for n-type PbSe involves reducing lattice thermal conductivity (κ lat ) by introducing various defect structures. However, lattice mismatches resulting from internal defects within the matrix can diminish carrier mobility, thereby affecting electrical transport properties. In this study, n-type AgCuTe-alloyed PbSe systems achieve a peak ZT value of ≈1.5 at 773 K. Transmission electron microscopy reveals nanoprecipitates of Ag 2 Te, the room temperature second phase of AgCuTe, within the PbSe matrix. Meanwhile, a unique semi-coherent phase boundary is observed between the PbSe matrix and the Ag 2 Te nanoprecipitates. This semi-coherent phase interface effectively scatters low-frequency phonons while minimizing damage to carrier mobility. Additionally, the dynamic doping effect of Cu atoms from the decomposition of AgCuTe within the matrix further optimize the high-temperature thermoelectric performance. Overall, these factors significantly enhance the ZT across the whole temperature range. The ZT value of ≈1.5 indicates high competitiveness compared to the latest reported n-type PbSe materials, suggesting that these findings hold promise for advancing the development of efficient thermoelectric systems.
研究领域:
材料科学
·
凝聚态物理
·
能源材料
·
纳米结构工程
·
热电转换
✓ 已验证
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2022
·Vol. 24
·期 44
·27105-27113
·
IF 3.945
Panpan Peng,Chao Wang,Lanwei Li,Shuyao Li,Jing Chen,Pengya Fan,Rui Du,Haotian Si,Zhenxiang Cheng,Jianli Wang
Endotaxial nanostructures can reduce lattice thermal conductivity through enhancing phonon scattering without affecting electrical transport, leading to a high thermoelectric performance. On the other hand, band engineering can enhance electrical transport by improving the Seebeck coefficient through valence band convergence and the resonance level. In this paper, the synergistic effect of band engineering and endotaxial nanostructures was implemented in SnTe thermoelectric materials by alloying with AgCuTe and doping with Indium. The positron annihilation lifetime spectra show that the vacancy concentration in SnTe was reduced after alloying with AgCuTe, which led to a decreasing hole concentration and improved carrier mobility. Additionally, the diffusion of Ag in the matrix during the preparation can facilitate valence band convergence. Therefore, the power factor of SnTe is greatly increased to 18 μW cm−1 K−2 at 800 K, which can be further increased to 21.4 μW cm−1 K−2 at 800 K after In doping due to resonance level formation. Meanwhile, Cu2Te endotaxial nanostructures also can be observed in the TEM image after SnTe alloying with AgCuTe. So, the lattice thermal conductivity significantly reduced to 0.93 W m−1 K −1 in In-doped and AgCuTe-alloyed SnTe. Finally, we obtain an enhanced ZT value of 1.14 in Sn1.02In0.01Te–1%AgCuTe at 800 K.
研究领域:
材料科学
·
凝聚态物理
·
功能材料
·
热电转换
·
纳米结构调控
·
半导体物理
·
能源材料
✓ 已验证
DOI
高影响因子
Physica Status Solidi-Rapid Research Letters
·
2020
·Vol. 14
·期 4
·1900723
·
IF 2.291
Yadan Deng,Jingzan Jiang,Jun Sun,Yufeng Hu,Qiuhong Cui,Zhenbo Deng,Zhidong Lou,Yanbing Hou,Feng Teng
Fabrication of nanowires in polymer films can dramatically enhance the mobility of thin-film transistors (TFTs). Unlike the popular method of forming nanowires after spin-coating films, here a water-bath method to fabricate the micrometer-long nanowires in the poly(3-hexylthiophene) (P3HT) solution is introduced, which is suitable for large-area printing electronic application. The resulting transistor exhibits significantly enhanced mobility and excellent device stability. However, the threshold voltage of the device is increased, compared with the amorphous film device. The underlying mechanism of the mesoscale crystalline induced threshold voltage increase has been rarely studied. The temperature-dependent characteristics imply that the activation energy of the device with nanowires is higher than that of the amorphous one, indicating nanowires can introduce deep traps. This suggests that the charge transport is mainly limited by the deep traps at the junctions between the nanowires considering the trap density inside the nanowires is significantly low. The deep traps introduced by the junctions can increase the threshold voltage as the device needs higher voltage to fill these traps in the channel before the device is turned on. This explains why the devices with nanowires have an increased threshold voltage while their mobilities are dramatically enhanced.
研究领域:
材料科学
·
凝聚态物理
·
有机电子学
·
薄膜晶体管
·
半导体器件物理
✓ 已验证
DOI
高影响因子
Advanced Electronic Materials
·
2021
·Vol. 8
·期 4
·2101125
·
IF 7.295
Qi-Qi Wang,Fan Li,Sheng-Qing Xia,Jian Liu,Xiao-Cun Liu,Ling Chen,Cheng-Qian Zhang
The single crystal growth of Mg 3 Bi 2 -based thermoelectric materials is of great significance for their applications near room temperature. So far, it is still a big challenge to grow such bulk single crystals and attempts are primarily focused on the metal flux methods. For the first time, bulk single crystals of n-type Mg 3 Bi 1.49 Sb 0.5 Te 0.01 are directly grown by applying an In-situ Loading Bridgman method. The as-grown single crystal features an excellent carrier mobility of 220 cm 2 V −1 s −1 , which is among the best compared to other Mg 3 Bi 2 -based bulk materials. Besides, this method is successfully developed to fast grow uniform polycrystalline materials with high thermoelectric and mechanic performance. As demonstrated by the single-leg device, a large temperature difference of 10.5 K is achieved at the supplied electric current of 0.6 A, much superior to other room temperature state-of-the-art thermoelectric materials. With the single crystalline and polycrystalline materials prepared reliably and conveniently, in-depth investigations on the Mg 3 Bi 2 thermoelectric system can be greatly benefited, which should as well significantly facilitate their practical applications at room temperature.
研究领域:
材料科学
·
热电学
·
凝聚态物理
·
晶体生长
·
功能材料
·
能源材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 21
·17029-17035
·
IF 3.289
Xiaoyu Zhang,Yu Zhang,Hua Wu,Long Yan,Zhenguang Wang,Jun Zhao,William W. Yu,Andrey L. Rogach
We explore two strategies to improve the performance of hybrid solar cells fabricated using poly(3-hexylthiophene) (P3HT) and colloidal PbSe nanocrystals, which have reached a 1 sun power conversion efficiency of 2.9%. Using an atomic passivation strategy towards inorganic ligand-capped nanocrystals, the electron mobilities of PbSe quantum dot films are improved from 1.95 × 10−6 cm2 V−1 s−1 to 1.15 × 10−5 cm2 V−1 s−1. Employing ultrasmall PbSe nanocrystals allows us to adjust their bandgaps towards the type II heterojunction with P3HT, thus achieving efficient charge separation and transfer between the polymer/inorganic constituents. The device performance dropped to half after 10 days' storage, and the P3HT/PbSe interface was found to play a primary role in this efficiency degradation.
研究领域:
材料科学
·
纳米科技
·
光伏技术
·
半导体物理
·
表面与界面化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）