Small Methods
·
2023
·
IF 12.4
Shanhong Wan,Shanshan Xiao,Mingquan Li,Xin Wang,Khak Ho Lim,Min Hong,Maria Ibáñez,Andreu Cabot,Yu Liu
Developing cost-effective and high-performance thermoelectric (TE) materials to assemble efficient TE devices presents a multitude of challenges and opportunities. Cu 3 SbSe 4 is a promising p -type TE material based on relatively earth abundant elements. However, the challenge lies in its poor electrical conductivity. Herein, an efficient and scalable solution-based approach is developed to synthesize high-quality Cu 3 SbSe 4 nanocrystals doped with Pb at the Sb site. After ligand displacement and annealing treatments, the dried powders are consolidated into dense pellets, and their TE properties are investigated. Pb doping effectively increases the charge carrier concentration, resulting in a significant increase in electrical conductivity, while the Seebeck coefficients remain consistently high. The calculated band structure shows that Pb doping induces band convergence, thereby increasing the effective mass. Furthermore, the large ionic radius of Pb 2+ results in the generation of additional point and plane defects and interphases, dramatically enhancing phonon scattering, which significantly decreases the lattice thermal conductivity at high temperatures. Overall, a maximum figure of merit ( zT max ) ≈ 0.85 at 653 K is obtained in Cu 3 Sb 0.97 Pb 0.03 Se 4 . This represents a 1.6-fold increase compared to the undoped sample and exceeds most doped Cu 3 SbSe 4 -based materials produced by solid-state, demonstrating advantages of versatility and cost-effectiveness using a solution-based technology.
研究领域:
材料科学
·
能源技术
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Khak Ho Lim,Yuxuan Xia,Lixiang Xu,Mingjun Zhao,Mingquan Li,Ye Cheng,Jiale Mao,Shuang Wang,Lei Chen,Sai Wing Tsang,Pingwei Liu,Qingyue Wang,Xuan Yang,Wen-Jun Wang,Andreu Cabot,Min Hong,Yu Zhang,Yu Liu
Ag 2 Se has emerged as a promising thermoelectric (TE) material for room-temperature applications. However, its TE performance is limited by the low carrier effective mass ( m* ) of only 0.1 m 0 , where m 0 represents the free electron mass. In this study, we employ a microwave-assisted method to synthesize nanostructured Ag 2-x Se with Pb doping that is found to increase m* to 0.4 m 0 . Accordingly, the Seebeck coefficient is significantly enhanced, which together with the high electrical conductivity, leads to enhanced electronic transport. The increase in m* is systematically investigated by density functional theory calculations and linked to the enhanced electronic by modeling simulations. The calculated band structures reveal that the hybridization of heavy Pb-6p orbitals flattens the conduction band edges, and thereby enhances m* . Furthermore, Pb doping significantly reduces the lattice thermal conductivity due to the high-density point defects, dislocations, and grain boundaries, as revealed by detailed electron microscopy characterizations. The synergy from both enhanced electronic transport and reduced phonon propagation yielded a maximum figure of merit of 1.04 at 376 K, and an average figure of merit of 1.0 for Pb-doped Ag 1.9 Se. The optimized TE performance is further validated in a flexible TE generator, which produced a maximum output power of 0.6 μW at a temperature difference of 45 K. These findings demonstrate that enhancing m* and increasing phonon-scattering using vacancy tuning and aliovalent doping effectively boosts the TE performance of Ag 2 Se, a strategy that can be extended to other TE materials to maximize their potentials for power generation and thermoelectric cooling applications.
研究领域:
材料科学
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凝聚态物理
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DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Honglei Wang,Zixuan Tian,Zhuang Fu,Lijun Zhao,Lei Wang,Songtao Dong,Hongbo Ju
Cu 3 SbSe 4 has garnered significant attention due to its low thermal conductivity, complex elemental composition, and economic feasibility. In this study, Cu 2.85 Ag 0.15 Sb 0.985−x Bi 0.015 Pb x Se 4 (x=0, 0.05, 0.10, and 0.15) samples were synthesized using a system of vacuum melting combined with cold isostatic pressing techniques. The impact of Pb doping on the thermoelectric properties of Cu 2.85 Ag 0.15 Sb 0.985 Bi 0.015 Se 4 was comprehensively investigated. The experimental results revealed a notable increase in carrier concentration, from 2.95×10 18 cm −3 to 8.31×10 19 cm −3 , leading to a substantial improvement on the electrical conductivity. At 573 K, the electrical conductivity of the Cu 2.85 Ag 0.15 Sb 0.835 Bi 0.015 Pb 0.15 Se 4 reached 234.26 S cm −1 , while the power factor of the Cu 2.85 Ag 0.15 Sb 0.885 Bi 0.015 Pb 0.10 Se 4 achieved a maximum value of 883.5 μW m −1 K −2 . The incorporation of Pb induced lattice defects, which modified the phonon mean free path and enhanced phonon scattering. As a result, the increased phonon scattering contributed to a reduction in lattice thermal conductivity within the Cu 2.85 Ag 0.15 Sb 0.985 Bi 0.015 Se 4 sample. The thermoelectric figure of merit (ZT) for the Cu 2.85 Ag 0.15 Sb 0.935 Bi 0.015 Pb 0.05 Se 4 reached a peak value of approximately 0.74 at 573 K, marking a 157.4% improvement compared to that of Cu 2.85 Ag 0.15 Sb 0.985 Bi 0.015 Se 4 (∼0.47). This study demonstrates that multi-element doping is a highly effective strategy for optimizing the thermoelectric properties of the Cu 3 SbSe 4 system.
研究领域:
材料科学
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热电材料研究
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
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IF 4.175
Boyi Wang,Yongli Wang,Shuqi Zheng,Shichao Liu,Juan Li,Siyi Chang,Teng An,Weilu Sun,Yuxuan Chen
Pb doped Cu 3 Sb 1-x Pb x Se 4 (x = 0, 0.01, 0.02, 0.04 and 0.06) compounds have been synthesized via microwave-assisted solvothermal method followed by SPS progress, and their thermoelectric properties from 300 K to 623 K has been explored. On one hand, Pb doping in the Sb site improved the electrical properties of Cu 3 SbSe 4 , on the other hand, the second phase PbSe formed at the high doping content (x ≥ 0.02) reduced the thermal conductivity by the phonon scattering. Altogether, the improvement of the electrical properties and decrease of the thermal conductivity results in a promising peak zT of ∼0.52 at 623 K of Cu 3 Sb 0.96 Pb 0.04 Se 4 sample, which is about 80% higher than that of the un-doped Cu 3 SbSe 4 . The current work provides a method which can reduce the thermal conductivity by forming heterojunction and also improve the electrical properties by doping of one element.
研究领域:
材料科学
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物理学
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DOI
高影响因子
Small
·
2021
·Vol. 17
·期 8
·2006111
·
IF 13.281
Mengxuan Yu,Xiaohu Yang,Yejun Zhang,Hongchao Yang,Haoying Huang,Zan Wang,Jinyi Dong,Rong Zhang,Ziqiang Sun,Chunyan Li,Qiangbin Wang
Ag 2 Se quantum dots (QDs) as an effective biological probe in the second near-infrared window (NIR-II, 1000–1700 nm) have been widely applied in bioimaging with high tissue penetration depth and high spatiotemporal resolution. However, the ions deficiency and crystal defects caused by the high Ag + mobility in Ag 2 Se crystals are mainly responsible for the inefficient photoluminescence (PL) of Ag 2 Se QDs. Herein, a tailored route is reported to achieve controllable doping of Ag 2 Se QDs in which Ag is exchanged by Pb via cation exchange (CE), which is unattainable by direct synthetic methods. The Pb-doped Ag 2 Se QDs (denoted as Pb:Ag 2 Se QDs) present fire-new optical features with significantly enhanced PL intensity of 4.2 folds. Photoelectron spectroscopy confirms that Pb acts as an n-type dopant for Ag 2 Se QDs and therefore the electronic impurities provide additional carriers to fill the traps. Moreover, the general validity of this method is demonstrated to convert different sized Ag 2 Se into Pb:Ag 2 Se QDs, so that a wide range of NIR-II PL with high intensity is obtained. The bright NIR-II emission of Pb:Ag 2 Se QDs is further successfully performed in lymphatic system mapping.
研究领域:
生物医学工程
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材料科学
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光学成像
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DOI
PubMed
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2020
·Vol. 22
·期 13
·7012-7020
·
IF 3.43
Qiang Zhang,Jichong Hou,Jianfeng Fan,Shaoping Chen,Wenhao Fan,Hua Zhang,Wenxian Wang,Yucheng Wu,Bingshe Xu
This work reports the electrical and thermal transport processes in p-type Pb-doped Mg3(1+x)Sb2−yPby (0.02 ≤ x ≤ 0.08; 0 ≤ y ≤ 0.02) compounds. Low-energy electron acceptor defects Mg vacancies are easy to form, which can provide holes and make p-type transport in the Mg3Sb2 matrix. However, with an increase in excess Mg, the transport behavior changes from p type to n type as manifested synergistically by both the Hall coefficient and Seebeck coefficient. This indicates the effective role of Mg in tuning carrier type and concentration for a pristine Mg3Sb2 compound. Upon substitution of Sb by Pb, the hole concentration slightly increases, and mobility is greatly improved by 133% at room temperature. The significant increase in mobility is attributed to the weakening ionized impurity scattering, stemming from the decreasing concentration induced by Pb doping. Thus, the power factor is enhanced with a 146% improvement at room temperature. Consequently, the figure of merit ZT of the Pb-doped sample is 1.8 times larger than the pristine one at around 300 K. Moreover, the non-degenerate transport behavior revealed by electrical properties is simply analyzed regarding the effects of minority carriers on the overall Seebeck coefficient. This study proposes a new strategy of charge compensation for improving mobility and a simple way to guide the prediction about the onset of bipolar conduction for Mg3Sb2-based compounds and other potential thermoelectric materials.
研究领域:
材料科学
·
热电学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·
IF 3.3
Qingyuan Cheng,Liman Li,Mingxia Yu
Silver chalcogenide (Ag2X; X = S, Se, Te) quantum dots (QDs) have facilitated the biomedical applications of QDs due to their low toxicity and tunable emission reaching the second near-infrared window (NIR-II window, 1000–1700 nm). The photoluminescence intensity of Ag2S QDs and Ag2Se QDs is considerably enhanced via Pb doping. However, the developed Pb-doped Ag2S QDs lacked in vivo verification, and the toxicity of the Pb-doped Ag2X QDs was only preliminarily assessed. Although QDs containing Pb have been widely introduced into the field of biomedicine, there are still concerns regarding toxicity associated with Pb. In the present study, we prepared polyethylene glycol (PEG)-modified Pb-doped Ag2S QDs with better biocompatibility and tested their in vivo bioimaging and toxicity in comparison with Ag2S QDs modified with the same PEG under identical concentrations. Results indicated that the PEG-modified Pb-doped Ag2S QDs significantly enhanced the brightness of in vivo bioimaging and spatial resolution for vessels inside the tumor without increasing toxicity, assessed based on cell viability post incubation for 96 h, intracellular ROS level, DNA damage, early apoptosis and mitochondrial injury. Our study demonstrated that the PEG-modified Pb-doped Ag2S QDs could serve as an advanced fluorescent probe for various biomedical applications.
研究领域:
生物医学工程
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材料科学
·
纳米技术
·
毒理学
✓ 已验证
产品关联
DOI
高影响因子