APPLIED PHYSICS LETTERS
·
2022
·Vol. 120
·期 19
·
IF 3.971
Wang Ping,Chen Jun-Liang,Zhou Qi,Liao Yun Tiao,Peng Ying,Liang Ji Sheng,Miao Lei
Ag 2 Se is an attractive candidate for room temperature thermoelectric applications because of its extremely low thermal conductivity, large power factor, and excellent mechanical properties. However, its performance is difficult to be improved effectively by doping other atoms. The traditional synthesis processes have the disadvantages of low yield, complex steps, and long period. In this study, the Ag 2 Se 1+ x samples were rapidly synthesized by the melting method via changing the ratio of Ag and Se. The carrier concentration and mobility of Ag 2 Se are optimized by adding excess Se, which could regulate non-stoichiometric defects in the process of synthesis. A high Seebeck coefficient of ∼136.0 μ V K −1 , a large power factor of ∼3000.0 μ W m −1 K −2 , and the maximum figure of merit ( ZT ) of ∼1.02 of the Ag 2 Se 1.015 sample have been achieved at 375 K. The ZT value is 2.3 times than that of the pristine sample (Ag 2 Se). The mechanical properties of the molting sample are comparable to state-of-the-art thermoelectric materials. Finally, the highest ZT value of the material is predicted by factor B . This work provides an idea for further optimizing Ag 2 Se-based and other non-stoichiometric thermoelectric semiconductors by a slight excess of Se. Moreover, the fast synthesis technology can significantly save time and energy, which manifests great advantages to the wholesale manufacturing industry.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 23
·4238
·
IF 5.719
Wenhang Wu,Zheng Liang,Meng Jia,Yuwei Li,Xiongcong Guan,Yunfeng Zhan,Jinxiu Wen,Jianyi Luo
A flexible thermoelectric device has been considered as a competitive candidate for powering wearable electronics. Here, we fabricated an n-type Ag2Se/Ag composite film on a flexible nylon substrate using vacuum-assisted filtration and a combination of cold and hot pressing. By optimising the Ag/Se ratio and the sequential addition and reaction time of AA, an excellent power factor of 2277.3 μW∙m−1K−2(corresponding to aZTof ~0.71) at room temperature was achieved. In addition, the Ag2Se/Ag composite film exhibits remarkable flexibility, with only 4% loss and 10% loss in electrical conductivity after being bent around a rod of 4 mm radius for 1000 cycles and 2000 cycles, respectively. A seven-leg flexible thermoelectric device assembled with the optimised film demonstrates a voltage of 19 mV and a maximum power output of 3.48 μW (corresponding power density of 35.5 W m−2) at a temperature difference of 30 K. This study provides a potential path to design improved flexible TE devices.Keywords:thermoelectricity;Ag2Se;Ag;composite film;flexible device
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-11
·
IF 15.7
Zhang Lin,Shi Xiao-Lei,Shang Hongjing,Gu Hongwei,Chen Wenyi,Li Meng,Huang Daxing,Dong Hao,Wang Xiaolei,Ding Fazhu,Chen Zhi-Gang
Flexible thermoelectric materials and devices hold enormous potential for wearable electronics but are hindered by inadequate material properties and inefficient assembly techniques, leading to suboptimal performance. Herein, we developed a flexible thermoelectric film, comprising Ag 2 Se nanowires as the primary material, a nylon membrane as a flexible scaffold, and reduced graphene oxide as a conductive network, achieving a record-high room-temperature ZT of 1.28. Hot-pressed Ag 2 Se nanowires exhibited strong (013) orientation, enhancing carrier mobility and electrical conductivity. Dispersed reduced graphene oxide further boosts electrical conductivity and induces an energy-filtering effect, decoupling electrical conductivity and the Seebeck coefficient to achieve an impressive power factor of 37 μW cm −1 K −2 at 300 K. The high-intensity between Ag 2 Se and reduced graphene oxide interfaces enhance phonon scattering, effectively reducing thermal conductivity to below 0.9 W m −1 K −1 and enabling the high ZT value. The nylon membrane endowed the film with exceptional flexibility. A large-scale out-of-plane device with 100 pairs of thermoelectric legs, assembled from these films, delivers an ultrahigh normalized power density of >9.8 μW cm −2 K −2 , outperforming all reported Ag 2 Se-based flexible devices. When applied to the human body, the device generated sufficient power to operate a thermo-hygrometer and a wristwatch, demonstrating its practical potential for wearable electronics.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Mairman Muska,Ye Wang,Jing Yang,Lin Ma,Qian Xu,Honghe Ding,Junfa Zhu,Qing Yang
With a dual strategy of phase-interface engineering, monolayer (1L)–1T-WSe2 integrated with Ag2Se nanoparticles (NPs) is in situ fabricated as quasi-monolayer Ag2Se/1L–1T-WSe2 hybrid nanosheets via a one-pot oleylamine-colloidal reaction. The Ag2Se NPs direct the growth of 1L–1T-WSe2 nanosheets forming the quasi-monolayer hybrid nanosheets by lodging in the interlayer spaces of WSe2 while the Ag2Se NPs being in a superionic conductor state diffuse rapidly and prevent the growth of piled-up multilayered WSe2 nanosheets. Due to the formation of quasi-monolayer Ag2Se/1L–1T-WSe2 nanosheets, many more side edges are exposed. Intensive studies illustrated that the quasi-monolayer Ag2Se/1L–1T-WSe2 hybrid nanosheets provide increased surface area and active sites as compared with isolated Ag2Se and WSe2. The hybrid nanosheets demonstrated excellent catalytic properties for hydrogen evolution reaction (HER) with overpotentials (η10) of 163 and 140 mV in acidic and basic conditions, respectively, and an outstanding alkaline supercapacitance of 1674 F g–1 at 1 A g–1. Meanwhile, X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS) determinations revealed that the quasi-monolayer hybrid nanosheets with enhanced electronic modulation could promote H+ adsorption/H2 desorption and accelerate the transport and separation of charge on the interface of heterostructured catalyst along with the electrode surface so as to exhibit outstanding electrochemical performances for HER and pseudocapacitance.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
RARE METALS
·
2017
·Vol. 37
·期 4
·333-342
·
IF 1.189
Feng Dan,Chen Yue-Xing,Fu Liang-Wei,Li Ju,He Jia-Qing
Earth-abundant IV–VI semiconductor SnSe is regarded as a promising thermoelectric material due to its intrinsic low thermal conductivity. In this report, the highly textured SnSe/Ag 2 Se composites were first designed by solid solution method followed by spark plasma sintering (SPS) and their thermoelectric properties in two directions were investigated, and then, the performance of composites was further optimized with an additional ball milling. The coexistence of SnSe and Ag 2 Se phases is clearly confirmed by energy-dispersive X-ray spectroscopy (EDX) in transmission electron microscopy (TEM). After ball milling, the size of SnSe grains as well as the incorporated Ag 2 Se particles reduces effectively, which synergistically optimizes the electrical and thermal transport properties at high temperature range. As a result, a maximum ZT of ~ 0.74 at 773 K for SnSe + 1.0%Ag 2 Se in the direction vertical to the pressing direction is achieved. Composite engineering with additional ball milling is thus proved to be an efficient way to improve the thermoelectric properties of SnSe, and this strategy could be applicable to other thermoelectric systems. Graphical
研究领域:
材料科学
·
热电材料
·
半导体物理
·
纳米结构工程
·
能源材料
✓ 已验证
DOI
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
·
凝聚态物理
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2016
·
IF 7.145
Huan Tang,Sheng-Tao Yang,Yi-Fan Yang,Da-Ming Ke,Jia-Hui Liu,Xing Chen,Haifang Wang,Yuanfang Liu
As a novel fluorescent probe in the second near-infrared window, Ag2Se quantum dots (QDs) exhibit great prospect in in vivo imaging due to their maximal penetration depth and negligible background. However, the in vivo behavior and toxicity of Ag2Se QDs still largely remain unknown, which severely hinders their wide-ranging biomedical applications. Herein, we systematically studied the blood clearance, distribution, transformation, excretion, and toxicity of polyethylene glycol (PEG) coated Ag2Se QDs in mice after intravenous administration with a high dose of 8 μmol/kg body weight. QDs are quickly cleared from the blood with a circulation half-life of 0.4 h. QDs mainly accumulate in liver and spleen and are remarkably transformed into Ag and Se within 1 week. Ag is excreted from the body readily through both feces and urine, whereas Se is excreted hardly. The toxicological evaluations demonstrate that there is no overt acute toxicity of Ag2Se QDs to mice. Moreover, in regard to the in vivo stability problem of Ag2Se QDs, the biotransformation and its related metabolism are intensively discussed, and some promising coating means for Ag2Se QDs to avert transformation are proposed as well. Our work lays a solid foundation for safe applications of Ag2Se QDs in bioimaging in the future.
研究领域:
生物医学
·
药理学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2023
·
IF 10.9
Yi-Yan Liao,Qiang Sun,Xu-Ping Jiang,Hao Wu,Bang-Zhou Tian,Ze-Gao Wang,Kun Zheng,Lei Yang
The coupling of charge carrier and phonon transport limits the application of Ag 2 Se as a low-toxic near-room-temperature thermoelectric material. Strategies that reduce the thermal conductivity via enhancing the phonon scattering usually lead to reduced carrier mobility due to high grain boundary potential barrier. In this study, we developed a cell-membrane-mimic grain boundary engineering strategy for decoupling the charge carrier and phonon scattering through decorating high-dielectric-constant rutile TiO 2 at Ag 2 Se grain boundaries to enable the charge carrier/phonon selective permeability. The nano-sized TiO 2 with high dielectric permittivity can secure the charge carrier transport by shielding the interfacial Coulomb potential to lower the energy barrier of grain boundaries, rendering an enhanced power factor. Additionally, benefited from the enhanced phonon scattering by TiO 2 nanoparticles, a significantly decreased lattice thermal conductivity of ∼0.20 W m −1 K −1 and a high zT of ∼0.97 at 390 K are obtained in the Ag 2 Se-based nanocomposites. This work demonstrates that such cell-membrane-mimic grain boundary engineering strategy may shed light on developing high-performance thermoelectric materials.
研究领域:
材料科学
·
物理学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2020
·
IF 8.758
Jie Chen,Qiang Sun,Deyu Bao,Taoyi Liu,Wei-Di Liu,Can Liu,Jun Tang,Dali Zhou,Lei Yang,Zhi-Gang Chen
Owing to the intrinsically good near-room-temperature thermoelectric performance, β-Ag2Se has been considered as a promising alternative to n-type Bi2Te3 thermoelectric materials. Herein, we develop an energy- and time-efficient wet mechanical alloying and spark plasma sintering method to prepare porous β-Ag2Se with hierarchical structures including high-density pores, a metastable phase, nanosized grains, semi-coherent grain boundaries, high-density dislocations, and localized strains, leading to an ultralow lattice thermal conductivity of ∼0.35 W m–1 K–1 at 300 K. A relatively high carrier mobility is obtained by adjusting the sintering temperature to obtain pores with an average size of ∼260 nm, therefore resulting in a figure of merit, zT, of ∼0.7 at 300 K and ∼0.9 at 390 K. The single parabolic band model predicts that zT of such porous β-Ag2Se can reach ∼1.1 at 300 K if the carrier concentration can be tuned to ∼1 × 1018 cm–3, suggesting that β-Ag2Se can be a competitive candidate for room-temperature thermoelectric applications.
研究领域:
材料科学
·
热电材料研究
✓ 已验证
DOI
PubMed
高影响因子
Nano Energy
·
2020
·
IF 16.602
Cong Jiang,Ping Wei,Yufei Ding,Kefeng Cai,Liang Tong,Qi Gao,Yao Lu,Wenyu Zhao,Song Chen
Flexible thermoelectric generator (f-TEG) has been considered to be a competitive candidate for powering wearable electronics and node sensor of internet-of-things. Herein, we report a polyvinylpyrrolidone (PVP)/Ag 2 Se composite film on nylon membrane prepared by first in-situ synthesis of PVP coated Ag 2 Se nanostructures (NSs), then vacuum assisted filtration of the NSs and finally hot pressing. High-resolution scanning and transmission electron microscope observations reveal that the PVP is located at the wall of pores and most Ag 2 Se grains are with coherent interfaces. Because of the unique microstructure and synergistic effect of the two components, an optimal composite film exhibits an ultrahigh power factor of ~ 1910 μW m −1 K −2 (corresponding ZT ~ 1.1) at 300 K and outstanding flexibility (only a 5.5% decrease in power factor after 1000 times bending around a 4 mm radius rod). An assembled 6-leg f-TEG produces 4.16 μW and the maximum power density is 28.8 W m −2 at a temperature difference of 29.1 K. This work demonstrates that insulating polymer can act as a great additive for improving both the TE properties and flexibility of inorganic TE films via fine design. The as-prepared composite film shows great promise for directly converting low-grade heat into electrical energy near room temperature.
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
Materials
·
2024
·Vol. 17
·期 15
·3784
·
IF 3.1
Yunhuan Yuan,Chaogang Ding,Rui Yin,Shun Lu,Jie Xu,Wei Ren,Kang Li,Weiwei Zhao
Flexible thermoelectric materials have drawn significant attention from researchers due to their potential applications in wearable electronics and the Internet of Things. Despite many reports on these materials, it remains a significant challenge to develop cost-effective methods for large-scale, patterned fabrication of materials that exhibit both excellent thermoelectric performance and remarkable flexibility. In this study, we have developed an Ag2Se-based ink with excellent printability that can be used to fabricate flexible thermoelectric films by screen printing and low-temperature sintering. The printed films exhibit a Seebeck coefficient of −161 μV/K and a power factor of 3250.9 μW/m·K2at 400 K. Moreover, the films demonstrate remarkable flexibility, showing minimal changes in resistance after being bent 5000 times at a radius of 5 mm. Overall, this research offers a new opportunity for the large-scale patterned production of flexible thermoelectric films.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Qi Gao,Wu Wang,Yao Lu,Kefeng Cai,Yating Li,Zixing Wang,Miaomiao Wu,Changjun Huang,Jiaqing He
Herein, we fabricated an Ag/Ag2Se composite film on a flexible nylon membrane with a high power factor and excellent flexibility. First, Ag nanoparticles and multiscale Ag2Se nanostructure composite powders were prepared by wet chemical synthesis using Se nanowires, silver nitrate, and l-ascorbic acid as raw materials, followed by vacuum-assisted filtration of the composite powders on a porous nylon membrane and then hot pressing. The optimized composite film shows a very high power factor of 1860.6 μW m–1 K–2 (with a corresponding electrical conductivity of 3958 S cm–1) at room temperature. The composite film retains 93.3% of the original electrical conductivity after 1000 bending cycles around a rod with a diameter of 8 mm. At a temperature difference of 27 K, an 8-leg thermoelectric prototype device assembled with the optimized composite film generates a maximum power of 7.14 μW with a corresponding power density of 8.74 W m–2. This work provides a new strategy to synthesize flexible thermoelectric films with both a high power factor and high electrical conductivity.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子