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1.
Adv Sci (Weinh) ; : e2409788, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-39352315

RESUMEN

With the advances in bulk Mg3Bi2, there is increasing interest in pursuing whether Mg3Bi2 can be fabricated into flexible thin films for wearable electronics to expand the practical applications. However, the development of fabrication processes for flexible Mg3Bi2 thin films and the effective enhancement of their thermoelectric performance remain underexplored. Here, magnetron sputtering and ex-situ annealing techniques is used to fabricate flexible Mg3Bi2 thermoelectric thin films with a power factor of up to 1.59 µW cm-1 K-2 at 60 °C, ranking as the top value among all reported n-type Mg3Bi2 thin films. Extensive characterizations show that ex-situ annealing, and optimized sputtering processes allow precise control over film thickness. These techniques ensure high adhesion of the films to various substrates, resulting in excellent flexibility, with <10% performance degradation after 500 bending cycles with a radius of 5 mm. Furthermore, for the first time, flexible thermoelectric devices are fabricated with both p-type and n-type Mg3Bi2 legs, which achieve an output power of 0.17 nW and a power density of 1.67 µW cm-2 at a very low temperature difference of 2.5 °C, highlighting the practical application potential of the device.

2.
Nat Commun ; 15(1): 8356, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333137

RESUMEN

Ag2Se shows significant potential for near-room-temperature thermoelectric applications, but its performance and device design are still evolving. In this work, we design a novel flexible Ag2Se thin-film-based thermoelectric device with optimized electrode materials and structure, achieving a high output power density of over 65 W m-2 and a normalized power density up to 3.68 µW cm-2 K-2 at a temperature difference of 42 K. By fine-tuning vapor selenization time, we strengthen the (013) orientation and carrier mobility of Ag2Se films, reducing excessive Ag interstitials and achieving a power factor of over 29 µW cm-1 K-2 at 393 K. A protective layer boosts flexibility of the thin film, retaining 90% performance after 1000 bends at 60°. Coupled with p-type Sb2Te3 thin films and rational simulations, the device shows rapid human motion response and precise servo motor control, highlighting the potential of high-performance Ag2Se thin films in advanced applications.

3.
Adv Sci (Weinh) ; : e2408374, 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39324659

RESUMEN

Due to its inherent ductility, Ag2S shows promise as a flexible thermoelectric material for harnessing waste heat from diverse sources. However, its thermoelectric performance remains subpar, and existing enhancement strategies often compromise its ductility. In this study, a novel Sn-doping-induced biphasic structuring approach is introduced to synergistically control electron and phonon transport. Specifically, Sn-doping is incorporated into Ag2S0.7Se0.3 to form a biphasic composition comprising (Ag, Sn)2S0.7Se0.3 as the primary phase and Ag2S0.7Se0.3 as the secondary phase. This biphasic configuration achieves a competitive figure-of-merit ZT of 0.42 at 343 K while retaining exceptional ductility, exceeding 90%. The dominant (Ag, Sn)2S0.7Se0.3 phase bolsters the initially low carrier concentration, with interfacial boundaries between the phases effectively mitigating carrier scattering and promoting carrier mobility. Consequently, the optimized power factor reaches 5 µW cm-1 K-2 at 343 K. Additionally, the formation of the biphasic structure induces diverse micro/nano defects, suppressing lattice thermal conductivity to a commendable 0.18 W m-1 K-1, thereby achieving optimized thermoelectric performance. As a result, a four-leg in-plane flexible thermoelectric device is fabricated, exhibiting a maximum power density of ≈49 µW cm-2 under the temperature difference of 30 K, much higher than that of organic-based flexible thermoelectric devices.

4.
Adv Mater ; : e2409275, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223847

RESUMEN

Environmental-friendless and high-performance thermoelectrics play a significant role in exploring sustainable clean energy. Among them, AgSbTe2 thermoelectrics, benefiting from the disorder in the cation sublattice and interface scattering from secondary phases of Ag2Te and Sb2Te3, exhibit low thermal conductivity and a maximum figure-of-merit ZT of 2.6 at 573 K via optimizing electrical properties and addressing phase transition issues. Therefore, AgSbTe2 shows considerable potential as a promising medium-temperature thermoelectric material. Additionally, with the increasing demands for device integration and portability in the information age, the research on flexible and wearable AgSbTe2 thermoelectrics aligns with contemporary development needs, leading to a growing number of research findings. This work provides a detailed and timely review of AgSbTe2-based thermoelectrics from materials to devices. Principles and performance optimization strategies are highlighted for the thermoelectric performance enhancement in AgSbTe2. The current challenges and future research directions of AgSbTe2-based thermoelectrics are pointed out. This review will guide the development of high-performance AgSbTe2-based thermoelectrics for practical applications.

5.
Chem Soc Rev ; 53(18): 9254-9305, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39143899

RESUMEN

With the increasing demand for energy and the climate challenges caused by the consumption of traditional fuels, there is an urgent need to accelerate the adoption of green and sustainable energy conversion and storage technologies. The integration of flexible thermoelectrics with other various energy conversion technologies plays a crucial role, enabling the conversion of multiple forms of energy such as temperature differentials, solar energy, mechanical force, and humidity into electricity. The development of these technologies lays the foundation for sustainable power solutions and promotes research progress in energy conversion. Given the complexity and rapid development of this field, this review provides a detailed overview of the progress of multifunctional integrated energy conversion and storage technologies based on thermoelectric conversion. The focus is on improving material performance, optimizing the design of integrated device structures, and achieving device flexibility to expand their application scenarios, particularly the integration and multi-functionalization of wearable energy conversion technologies. Additionally, we discuss the current development bottlenecks and future directions to facilitate the continuous advancement of this field.

6.
Nat Commun ; 15(1): 6640, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103324

RESUMEN

Immune checkpoint inhibitor (ICI)-induced myocarditis involves intensive immune/inflammation activation; however, its molecular basis is unclear. Here, we show that gasdermin-E (GSDME), a gasdermin family member, drives ICI-induced myocarditis. Pyroptosis mediated by GSDME, but not the canonical GSDMD, is activated in myocardial tissue of mice and cancer patients with ICI-induced myocarditis. Deficiency of GSDME in male mice alleviates ICI-induced cardiac infiltration of T cells, macrophages, and monocytes, as well as mitochondrial damage and inflammation. Restoration of GSDME expression specifically in cardiomyocytes, rather than myeloid cells, in GSDME-deficient mice reproduces ICI-induced myocarditis. Mechanistically, quantitative proteomics reveal that GSDME-dependent pyroptosis promotes cell death and mitochondrial DNA release, which in turn activates cGAS-STING signaling, triggering a robust interferon response and myocardial immune/inflammation activation. Pharmacological blockade of GSDME attenuates ICI-induced myocarditis and improves long-term survival in mice. Our findings may advance the understanding of ICI-induced myocarditis and suggest that targeting the GSDME-cGAS-STING-interferon axis may help prevent and manage ICI-associated myocarditis.


Asunto(s)
Inhibidores de Puntos de Control Inmunológico , Proteínas de la Membrana , Miocarditis , Nucleotidiltransferasas , Piroptosis , Animales , Miocarditis/inmunología , Miocarditis/patología , Miocarditis/inducido químicamente , Miocarditis/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Ratones , Masculino , Humanos , Nucleotidiltransferasas/metabolismo , Nucleotidiltransferasas/genética , Transducción de Señal , Ratones Endogámicos C57BL , Ratones Noqueados , ADN Mitocondrial/metabolismo , ADN Mitocondrial/genética , Femenino , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Miocitos Cardíacos/efectos de los fármacos , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Proteínas de Unión a Fosfato/metabolismo , Proteínas de Unión a Fosfato/genética , Gasderminas
7.
Nanoscale Horiz ; 9(9): 1574-1581, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39034818

RESUMEN

We report two previously undiscovered phases of GeTe including the sphalerite (c-) phase and the hexagonal (h-) phase with interlayer van der Waals gaps. A polymorphic phase transformation from rhombohedral α-GeTe to c- and h-GeTe at near room temperature is first realized via electron beam irradiation. Their underlying thermodynamics and kinetics are illustrated using the in situ heating experiments and molecular dynamics simulations. Density-functional theory calculations indicate that c-GeTe exhibits typical metallic behavior and h-GeTe is a narrow-gap semiconductor with a strong spin-orbital coupling effect. Our findings shed light on a strategy for designing GeTe-based quantum devices compromising nanopillars and heterostructures via an atomic-scale electron beam lithography technique.

8.
Nat Commun ; 15(1): 6074, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39025911

RESUMEN

One-dimensional metallic transition-metal chalcogenide nanowires (TMC-NWs) hold promise for interconnecting devices built on two-dimensional (2D) transition-metal dichalcogenides, but only isotropic growth has so far been demonstrated. Here we show the direct patterning of highly oriented Mo6Te6 NWs in 2D molybdenum ditelluride (MoTe2) using graphite as confined encapsulation layers under external stimuli. The atomic structural transition is studied through in-situ electrical biasing the fabricated heterostructure in a scanning transmission electron microscope. Atomic resolution high-angle annular dark-field STEM images reveal that the conversion of Mo6Te6 NWs from MoTe2 occurs only along specific directions. Combined with first-principles calculations, we attribute the oriented growth to the local Joule-heating induced by electrical bias near the interface of the graphite-MoTe2 heterostructure and the confinement effect generated by graphite. Using the same strategy, we fabricate oriented NWs confined in graphite as lateral contact electrodes in the 2H-MoTe2 FET, achieving a low Schottky barrier of 11.5 meV, and low contact resistance of 43.7 Ω µm at the metal-NW interface. Our work introduces possible approaches to fabricate oriented NWs for interconnections in flexible 2D nanoelectronics through direct metal phase patterning.

9.
Medicine (Baltimore) ; 103(24): e38298, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38875421

RESUMEN

INTRODUCTION: Most adrenal tumors are benign and primary adrenal malignancies are relatively rare. Primary adrenal lymphoma (PAL) is a very rare and highly aggressive malignant tumor with unknown etiology, atypical clinical symptoms, nonspecific imaging manifestations, difficult disease diagnosis and poor prognosis. CASE REPORT: This case report details a 42-year-old woman who was admitted to the hospital with a 1-year-old bilateral adrenal mass and 1-month-old left upper abdominal pain. Enhanced CT of the abdomen showed a right adrenal nodule and a large occupying lesion in the left adrenal region, with a high probability of pheochromocytoma. Intraoperatively, a huge tumor measuring about 12*12*10 cm was found in the left adrenal region, infiltrating the left kidney, spleen and pancreatic tail. Postoperative pathology: lymphocytes were found in the renal capsule and subcapsule, lymphocytes were found in the pancreas; lymphocytes were found in the spleen. Consider a tumor of the lymphohematopoietic system, possibly lymphoma. CONCLUSION: This case demonstrates that primary adrenal diffuse large B-cell lymphoma (PADLBCL) is highly aggressive, has a poor prognosis, is prone to recurrence, has poor therapeutic outcomes, and is difficult to diagnose. Clinicians should consider the possibility of PADLBCL when encountering huge adrenal-occupying lesions and consider chemotherapy before surgery. Reducing the tumor size before surgery is a more favorable therapeutic approach, thus prolonging the patient life and improving the quality of survival.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Linfoma de Células B Grandes Difuso , Humanos , Femenino , Linfoma de Células B Grandes Difuso/patología , Linfoma de Células B Grandes Difuso/diagnóstico , Neoplasias de las Glándulas Suprarrenales/patología , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/cirugía , Adulto , Tomografía Computarizada por Rayos X , Glándulas Suprarrenales/patología , Glándulas Suprarrenales/diagnóstico por imagen , Glándulas Suprarrenales/cirugía
10.
Appl Opt ; 63(12): 3130-3137, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38856457

RESUMEN

Numerous applications at the photon-starved regime require a free-space coupling single-photon detector with a large active area, low dark count rate (DCR), and superior time resolutions. Here, we developed a superconducting microstrip single-photon detector (SMSPD), with a large active area of 260 µm in diameter, a DCR of ∼5k c p s, and a low time jitter of ∼171p s, operated at a near-infrared of 1550 nm and a temperature of ∼2.0K. As a demonstration, we applied the detector to a single-pixel galvanometer scanning system and successfully reconstructed the object information in depth and intensity using a time-correlated photon counting technology.

11.
NPJ Precis Oncol ; 8(1): 100, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740834

RESUMEN

Anaplastic lymphoma kinase (ALK) fusion-positive colorectal cancer (CRC) is a rare and chemotherapy-refractory subtype that lacks established and effective treatment strategies. Additionally, the efficacy and safety of ALK inhibitors (ALKi) in CRC remain undetermined. Herein, we examined a series of ALK-positive CRC patients who underwent various lines of ALKi treatment. Notably, we detected an ALK 1196M resistance mutation in a CRC patient who received multiple lines of chemotherapy and ALKi treatment. Importantly, we found that Brigatinib and Lorlatinib demonstrated some efficacy in managing this patient, although the observed effectiveness was not as pronounced as in non-small cell lung cancer cases. Furthermore, based on our preliminary analyses, we surmise that ALK-positive CRC patients are likely to exhibit inner resistance to Cetuximab. Taken together, our findings have important implications for the treatment of ALK-positive CRC patients.

12.
Nat Commun ; 15(1): 4242, 2024 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-38762562

RESUMEN

P-type Fe3CoSb12-based skutterudite thin films are successfully fabricated, exhibiting high thermoelectric performance, stability, and flexibility at medium-to-high temperatures, based on preparing custom target materials and employing advanced pulsed laser deposition techniques to address the bonding challenge between the thin films and high-temperature flexible polyimide substrates. Through the optimization of fabrication processing and nominal doping concentration of Ce, the thin films show a power factor of >100 µW m-1 K-2 and a ZT close to 0.6 at 653 K. After >2000 bending cycle tests at a radius of 4 mm, only a 6 % change in resistivity can be observed. Additionally, the assembled p-type Fe3CoSb12-based flexible device exhibits a power density of 135.7 µW cm-2 under a temperature difference of 100 K with the hot side at 623 K. This work fills a gap in the realization of flexible thermoelectric devices in the medium-to-high-temperature range and holds significant practical application value.

13.
Adv Mater ; 36(37): e2313146, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38608290

RESUMEN

Thermoelectric technology, which enables a direct and pollution-free conversion of heat into electricity, provides a promising path to address the current global energy crisis. Among the broad range of thermoelectric materials, silver copper chalcogenides (AgCuQ, Q = S, Se, Te) have garnered significant attention in thermoelectric community in light of inherently ultralow lattice thermal conductivity, controllable electronic transport properties, excellent thermoelectric performance across various temperature ranges, and a degree of ductility. This review epitomizes the recent progress in AgCuQ-based thermoelectric materials, from the optimization of thermoelectric performance to the rational design of devices, encompassing the fundamental understanding of crystal structures, electronic band structures, mechanical properties, and quasi-liquid behaviors. The correlation between chemical composition, mechanical properties, and thermoelectric performance in this material system is also highlighted. Finally, several key issues and prospects are proposed for further optimizing AgCuQ-based thermoelectric materials.

14.
Nat Commun ; 15(1): 3426, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654020

RESUMEN

Single-walled carbon nanotubes (SWCNTs)-based thermoelectric materials, valued for their flexibility, lightweight, and cost-effectiveness, show promise for wearable thermoelectric devices. However, their thermoelectric performance requires significant enhancement for practical applications. To achieve this goal, in this work, we introduce rational "triple treatments" to improve the overall performance of flexible SWCNT-based films, achieving a high power factor of 20.29 µW cm-1 K-2 at room temperature. Ultrasonic dispersion enhances the conductivity, NaBH4 treatment reduces defects and enhances the Seebeck coefficient, and cold pressing significantly densifies the SWCNT films while preserving the high Seebeck coefficient. Also, bending tests confirm structural stability and exceptional flexibility, and a six-legged flexible device demonstrates a maximum power density of 2996 µW cm-2 at a 40 K temperature difference, showing great application potential. This advancement positions SWCNT films as promising flexible thermoelectric materials, providing insights into high-performance carbon-based thermoelectrics.

15.
Neuron ; 112(11): 1795-1814.e10, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38518778

RESUMEN

Although bile acids play a notable role in depression, the pathological significance of the bile acid TGR5 membrane-type receptor in this disorder remains elusive. Using depression models of chronic social defeat stress and chronic restraint stress in male mice, we found that TGR5 in the lateral hypothalamic area (LHA) predominantly decreased in GABAergic neurons, the excitability of which increased in depressive-like mice. Upregulation of TGR5 or inhibition of GABAergic excitability in LHA markedly alleviated depressive-like behavior, whereas down-regulation of TGR5 or enhancement of GABAergic excitability facilitated stress-induced depressive-like behavior. TGR5 also bidirectionally regulated excitability of LHA GABAergic neurons via extracellular regulated protein kinases-dependent Kv4.2 channels. Notably, LHA GABAergic neurons specifically innervated dorsal CA3 (dCA3) CaMKIIα neurons for mediation of depressive-like behavior. LHA GABAergic TGR5 exerted antidepressant-like effects by disinhibiting dCA3 CaMKIIα neurons projecting to the dorsolateral septum (DLS). These findings advance our understanding of TGR5 and the LHAGABA→dCA3CaMKIIα→DLSGABA circuit for the development of potential therapeutic strategies in depression.


Asunto(s)
Depresión , Neuronas GABAérgicas , Área Hipotalámica Lateral , Receptores Acoplados a Proteínas G , Animales , Masculino , Ratones , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Depresión/metabolismo , Modelos Animales de Enfermedad , Neuronas GABAérgicas/metabolismo , Neuronas GABAérgicas/fisiología , Área Hipotalámica Lateral/metabolismo , Ratones Endogámicos C57BL , Vías Nerviosas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Núcleos Septales/metabolismo , Derrota Social , Estrés Psicológico/metabolismo
16.
Ther Adv Med Oncol ; 16: 17588359241230752, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38425989

RESUMEN

Background: Patients with initially unresectable colorectal cancer liver metastases (IU-CRLM) might benefit from using an effective systemic treatment followed by resection of liver metastases but the curative success rate is quite low. Indeed, nearly one-third of patients exhibit early recurrence within the first 6 months after surgery, and these individuals often have poor overall survival. Objectives: This study aims to clarify the application value of serial circulating tumor DNA (ctDNA) analysis in predicting the clinical outcome of IU-CRLM patients following liver metastasectomy. Design: A retrospective study was conducted on a cohort of patients with IU-CRLM between February 2018 and April 2021. Methods: Plasma samples at different time points during CRLM treatment [baseline (BL), preoperation (PRE), postoperation (POST), end-of-treatment (EOT), and progressive disease (PD)] were retrospectively collected from patients with initially unresectable CRLM enrolled at the Sun Yat-sen University Cancer Center. Dynamic changes of SEPTIN 9 (SEPT9) and Neuropeptide Y (NPY) methylated circulating tumor DNA (MetctDNA) levels in serial plasma samples were detected using droplet-digital PCR (ddPCR). Results: SEPT9 and NPY genes were hypermethylated in colon cancer cell lines and tissues while no difference was observed between primary and metastatic tumors. Patients with MetctDNA positive at POST or EOT had significantly lower recurrence-free survival (RFS) compared to patients with MetctDNA negative at these time points [POST: Hazard ratio (HR) 9.44, 95% confidence interval (CI) 5.15-17.30, p < 0.001; EOT: HR 11.48, 95% CI 3.27-40.31, p < 0.001]. Multivariate analysis demonstrated that POST (OR 33.96, 95% CI 4.03-286.10, p = 0.001) and EOT (OR 18.36, 95% CI 1.14-295.71, p = 0.04) MetctDNA was an independent risk factor for early recurrence. Time-dependent receiver operating characteristic curve (T-ROC) analysis revealed that area under the curve (AUC) value was greatest at the relapse time point of 6 months post-intervention, with POST-AUC and EOT-AUC values of 0.74 (95% CI 0.66-0.81) and 0.73 (95% CI 0.53-0.94), respectively. Serial MetctDNA analysis showed that RFS was significantly lower in patients with no MetctDNA clearance compared with those with MetctDNA clearance (HR 26.05, 95% CI 4.92-137.81, p < 0.001). Conclusion: Our study confirmed that serial ctDNA analysis of NPY and SEPT9 gene methylation could effectively predict early recurrence in IU-CRLM patients, especially at POST and EOT.

17.
J Colloid Interface Sci ; 664: 136-145, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38460379

RESUMEN

Extracting functional materials from industrial waste residues to absorb organic dyes can maximize waste reuse and minimize water pollution. However, the extraordinarily low purification efficiency still limits the practical application of this strategy. Herein, the lamellar NiOOH is in-situ anchored on the industrial waste red mud surface (ARM/NiOOH) as an adsorbent to purify organic dyes in wastewater. ARM/NiOOH adsorbent with high specific surface area and porosity provides considerable active sites for the congo red (CR), thereby significantly enhancing the removal efficiency of CR. Besides, we fit a reasonable adsorption model for ARM/NiOOH adsorbent and investigate its adsorption kinetics. Resultantly, ARM/NiOOH adsorbent can remarkably adsorb 348.0 mg g-1 CR within 5 min, which is 7.91 times that of raw RM. Our work provides a strategy for reusing industrial waste and purifying sewage pollution, which advances wastewater treatment engineering.

18.
Chem Asian J ; 19(10): e202400130, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38380867

RESUMEN

The creation of hierarchical nanostructures can effectively strengthen phonon scattering to reduce lattice thermal conductivity for improving thermoelectric properties in inorganic solids. Here, we use Zn doping to induce a remarkable reduction in the lattice thermal conductivity in SnTe, approaching the theoretical minimum limit. Microstructure analysis reveals that ZnTe nanoprecipitates can embed within SnTe grains beyond the solubility limit of Zn in the Zn alloyed SnTe. These nanoprecipitates result in a substantial decrease of the lattice thermal conductivity in SnTe, leading to an ultralow lattice thermal conductivity of 0.50 W m-1 K-1 at 773 K and a peak ZT of ~0.48 at 773 K, marking an approximately 45 % enhancement compared to pristine SnTe. This study underscores the effectiveness of incorporating ZnTe nanoprecipitates in boosting the thermoelectric performance of SnTe-based materials.

19.
Nat Commun ; 15(1): 923, 2024 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-38296942

RESUMEN

Exploring new near-room-temperature thermoelectric materials is significant for replacing current high-cost Bi2Te3. This study highlights the potential of Ag2Se for wearable thermoelectric electronics, addressing the trade-off between performance and flexibility. A record-high ZT of 1.27 at 363 K is achieved in Ag2Se-based thin films with 3.2 at.% Te doping on Se sites, realized by a new concept of doping-induced orientation engineering. We reveal that Te-doping enhances film uniformity and (00l)-orientation and in turn carrier mobility by reducing the (00l) formation energy, confirmed by solid computational and experimental evidence. The doping simultaneously widens the bandgap, resulting in improved Seebeck coefficients and high power factors, and introduces TeSe point defects to effectively reduce the lattice thermal conductivity. A protective organic-polymer-based composite layer enhances film flexibility, and a rationally designed flexible thermoelectric device achieves an output power density of 1.5 mW cm-2 for wearable power generation under a 20 K temperature difference.

20.
J Am Chem Soc ; 146(2): 1681-1689, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38178655

RESUMEN

The coupled relationship between carrier and phonon scattering severely limits the thermoelectric performance of n-type GeTe materials. Here, we provide an efficient strategy to enlarge grains and induce vacancy clusters for decoupling carrier-phonon scattering through the annealing optimization of n-type GeTe-based materials. Specifically, boundary migration is used to enlarge grains by optimizing the annealing time, while vacancy clusters are induced through the aggregation of Ge vacancies during annealing. Such enlarged grains can weaken carrier scattering, while vacancy clusters can strengthen phonon scattering, leading to decoupled carrier-phonon scattering. As a result, a ratio between carrier mobility and lattice thermal conductivity of ∼492.8 cm3 V-1 s-1 W-1 K and a peak ZT of ∼0.4 at 473 K are achieved in Ge0.67Pb0.13Bi0.2Te. This work reveals the critical roles of enlarged grains and induced vacancy clusters in decoupling carrier-phonon scattering and demonstrates the viability of fabricating high-performance n-type GeTe materials via annealing optimization.

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