Showing papers by "Qian Zhang published in 2021"
TL;DR: In this article, a review of recent advances achieved in wide thermoelectric (TE) related technologies are reviewed from the view of materials to devices, including the specific structural designs and working principles of the FTE devices, the properties of the materials involved, the manufacturing strategies for device assembly, and their real functioning performances.
Abstract: Thermoelectric (TE) materials/devices that can directly convert thermal energy into electricity provide a promising solution for sustainable energy development. As the flexible power supplies are urgently required for miniaturized and portable electronics, the development of flexible TE (FTE) devices, which have widespread application in the fields of power generation, flexible electronics, and wearable devices, has gained widespread attention. Over the past decades, research has largely focused on enhancing the ZT values of FTE materials and developing high-efficiency FTE generators (FTEGs). However, it is noted that in the past five years, research into FTE technologies is no longer confined to the electronic FTE materials and FTEGs. Many novel FTE applications, including self-powered multifunctional FTE sensors, ionic TE devices based on the Soret effect, multi-technology integrated TE devices, and even evaporation-driven quasi-TE nanogenerators, are emerging and demonstrate great practical significance. In this paper, recent advances achieved in wide FTE-related technologies are reviewed from the view of materials to devices. The specific structural designs and working principles of the FTE devices, the properties of the materials involved, the manufacturing strategies for device assembly, and their real functioning performances are comprehensively addressed with a few representative examples. Finally, several conclusions and future prospects for the development of FTE materials and devices are also provided. This review features a comprehensive understanding of the development roadmap for FTEs, which will help to guide future studies on flexible thermal energy harvesting/sensing applications and self-powered wearable electronics.
65 citations
TL;DR: In this paper, a spectrally stable and efficient pure red perovskite LED was developed by employing sequential ligand post-treated CsPbI3 quantum dots (QDs).
Abstract: Metal halide perovskites are promising semiconductors for next-generation light-emitting diodes (LEDs) due to their high luminance, excellent color purity, and handily tunable band gap. However, it remains a great challenge to develop perovskite LEDs (PeLEDs) with pure red emission at the wavelength of 630 nm. Herein, we report a spectrally stable and efficient pure red PeLED by employing sequential ligand post-treated CsPbI3 quantum dots (QDs). The synthesized CsPbI3 QDs with a size of ∼5 nm are treated in sequential steps using the ligands of 1-hydroxy-3-phenylpropan-2-aminium iodide (HPAI) and tributylsulfonium iodide (TBSI), respectively. The CsPbI3 QD films exhibit improved optoelectronic properties, which enables the fabrication of a pure red PeLED with a peak external quantum efficiency (EQE) of 6.4% and a stable EL emission centered at the wavelength of 630 nm. Our reported sequential ligand post-treatment strategy opens a new route to improve the stability and efficiency of PeLEDs based on QDs.
46 citations
TL;DR: Zhang et al. as mentioned in this paper identified potent antibodies binding to SARS-CoV-2 Spike protein from COVID-19 convalescent patients, and P4A1 was subsequently engineered to reduce the potential risk for Antibody-Dependent Enhancement of infection and to extend its half-life.
Abstract: COVID-19 pandemic caused by SARS-CoV-2 constitutes a global public health crisis with enormous economic consequences. Monoclonal antibodies against SARS-CoV-2 can provide an important treatment option to fight COVID-19, especially for the most vulnerable populations. In this work, potent antibodies binding to SARS-CoV-2 Spike protein were identified from COVID-19 convalescent patients. Among them, P4A1 interacts directly with and covers majority of the Receptor Binding Motif of the Spike Receptor-Binding Domain, shown by high-resolution complex structure analysis. We further demonstrate the binding and neutralizing activities of P4A1 against wild type and mutant Spike proteins or pseudoviruses. P4A1 was subsequently engineered to reduce the potential risk for Antibody-Dependent Enhancement of infection and to extend its half-life. The engineered antibody exhibits an optimized pharmacokinetic and safety profile, and it results in complete viral clearance in a rhesus monkey model of COVID-19 following a single injection. These data suggest its potential against SARS-CoV-2 related diseases.
44 citations
TL;DR: In this paper, a 4-leg flexible thermoelectric generator composed of the Ag1.8Se (x = 1.6, 1.8, 2.0, and 2.2) films was successfully deposited on the polyimide substrate by thermal evaporation.
37 citations
TL;DR: In this article, a terbium phosphonate chain complex was synthesized through assembly of electron-rich phosphonates units, electron-deficient polypyridine components and paramagnetic Tb3+ ions.
Abstract: Crystalline complexes that exhibited light switchable proton conductivity are of great interest but still a challenge in material science. Herein, a terbium phosphonate chain complex was synthesized through assembly of electron-rich phosphonate units, electron-deficient polypyridine components and paramagnetic Tb3+ ions. Via light irradiation and heat treatment, the photogenerated radicals could simultaneously and reversibly tune the photochromic, luminescent and magnetic properties. Originated from the abundant hydrogen bonding networks formed between PO3 groups and lattice water molecules, proton conductive behaviour was explored with high proton conductivity of (1.74±0.19)×10−3 S cm−1 at 80 °C and 100% relative humidity. Importantly, accompanied with the colorless sample changed to blue, the proton conductivity increased about 20% after room temperature light illumination, implying that light irradiation could act as an external stimulus to enhance the conductive properties of original material. This work innovatively realized the light responsive conductive property in the electron transfer photochromic materials, providing a novel strategy for the construction of smart materials.
36 citations
TL;DR: In this article, an n-type TiCoSb-based half-Heusler was fabricated by arc melting, ball milling, and spark plasma sintering.
33 citations
TL;DR: In this article, a 1/3 power law between thermal conductivity and length of a NbSe3 nanowire is observed, pointing towards a superdiffusive heat transport regime.
Abstract: Fascinating phenomena can occur as charge and/or energy carriers are confined in one dimension1–4. One such example is the divergent thermal conductivity (κ) of one-dimensional lattices, even in the presence of anharmonic interatomic interactions—a direct consequence of the Fermi–Pasta–Ulam–Tsingou paradox proposed in 19555. This length dependence of κ, also known as superdiffusive phonon transport, presents a classical anomaly of continued interest6–9. So far the concept has remained purely theoretical, because isolated single atomic chains of sufficient length have been experimentally unattainable. Here we report on the observation of a length-dependent κ extending over 42.5 µm at room temperature for ultrathin van der Waals crystal NbSe3 nanowires. We found that κ follows a 1/3 power law with wire length, which provides experimental evidence pointing towards superdiffusive phonon transport. Contrary to the classical size effect due to phonon-boundary scattering, the observed κ shows a 25-fold enhancement as the characteristic size of the nanowires decreases from 26 to 6.8 nm while displaying a normal–superdiffusive transition. Our analysis indicates that these intriguing observations stem from the transport of one-dimensional phonons excited as a result of elastic stiffening with a fivefold enhancement of Young’s modulus. The persistent divergent trend of the observed thermal conductivity with sample length reveals a real possibility of creating novel van der Waals crystal-based thermal superconductors with κ values higher than those of any known materials. A 1/3 power law between thermal conductivity and length of a NbSe3 nanowire is observed, pointing towards a superdiffusive heat transport regime.
30 citations
TL;DR: In this article, PbTe, GeTe, and MnTe are coalloyed with SnTe to form a single-phase solid solution, and the configuration entropy increases and phonon scattering is strongly enhanced.
Abstract: Entropy is a physical quantity gauging the degree of chaos in the system. High entropy alloying is thus an effective strategy to reduce the lattice thermal conductivity of the thermoelectric materials. In this paper, PbTe, GeTe, and MnTe are coalloyed with SnTe to form a single-phase solid solution. Because of the inclusion of various elements at the cationic (Sn2+) site, the configurational entropy increases, and the phonon scattering is strongly enhanced, leading to a reduced lattice thermal conductivity. In addition, the Seebeck coefficient is improved because of the band modification via this coalloying. Ga is then further doped to optimize the carrier concentration to ∼5.7 × 1020 cm-3 and reduce the room-temperature lattice thermal conductivity to ∼0.6 W m-1 K-1. Finally, a high peak ZT value of ∼1.52 at 823 K and an average ZT value ∼1.0 from 323 to 823 K were obtained in Ga0.025(Sn0.25Pb0.25Mn0.25Ge0.25)0.975Te.
30 citations
TL;DR: The photogeneration of stable radicals is important but still challenging in the field of optical switching, displays, and other devices as mentioned in this paper, and a simple radical-actuated photochromic molecule was found to exhibit photochromism and photomagnetism after lamp light irradiation.
29 citations
10 Jul 2021
TL;DR: Catalytic asymmetric aza-Michael represents one of the most convenient and atom-economical approaches for the rapid construction of biologically active chiral β-amino acid frameworks.
Abstract: Catalytic asymmetric aza-Michael represents one of the most convenient and atom-economical approaches for the rapid construction of biologically active chiral β-amino acid frameworks. However, the ...
29 citations
TL;DR: In this paper, the spectral properties of the electromagnetic responses are summarized into single-band and multi-band spectral modulations, and a perspicuous mainline for existing spectral controlling work and to inspire other innovative optical tuning for potential energy applications is provided.
TL;DR: In this article, a rice plant resistance to the phloem-feeding brown planthopper (BPH) is associated with fortification of sclerenchyma tissue, which is located just beneath the epidermis and a cell layer or two away from the vascular bundle in the rice leaf sheath.
TL;DR: In this article, the authors used Co doping to achieve peak ZTs of 0.65 in n-type and p-type pseudo-ternary half-Heusler alloys.
19 May 2021
TL;DR: In this article, a wearable thermoelectric generator using human body temperature is proposed for wearable electronics, which has a low thermal bypass and an efficient thermal contact interface, resulting in a peak power density of ∼20.6μW/cm2 when placed on a human arm at an ambient temperature of 289 K (air velocity, 1.1m/s).
Abstract: Summary A wearable thermoelectric generator using human body temperature is a promising power supply for wearable electronics. Here we discuss the design and fabrication of one kind of wearable thermoelectric generator constructed by n-type Mg3.2Bi1.498Sb0.5Te0.002 legs, p-type Bi0.4Sb1.6Te3 legs, polyurethane matrices, and flexible Cu/polyimide electrodes. The proposed device has a low thermal bypass and an efficient thermal contact interface, resulting in a peak power density of ∼20.6 μW/cm2 when placed on a human arm at an ambient temperature of 289 K (air velocity, 1.1 m/s) and a high peak power density of 13.8 mW/cm2 at a temperature difference of 50 K. In addition, it can withstand 10,000 bending cycles at a bend radius of 13.4 mm, suggesting that the proposed wearable thermoelectric generator has the potential to be a real-time power supply for certain wearable electronics in daily life.
TL;DR: In this paper, the authors reveal a mechanism for thermal conductivity reduction in a Zintl phase thermoelectric based on length scales for disorder in Eu2ZnSb2.
Abstract: The Zintl thermoelectric phase Eu2ZnSb2 has a remarkable combination of high mobility and low thermal conductivity that leads to good thermoelectric performance. The key feature of this compound is a crystal structure that has a Zn-site with a 50% occupancy. Here we use comparison of experimental thermal conductivity measurements and first principles thermal conductivity calculations to characterize the thermal conductivity reduction. We find that partial ordering, characterized by local order, but Zn-site disorder on longer scales, leads to an intrinsic nanostructuring induced reduction in thermal conductivity, while retaining electron mobility. This provides a direction for identifying Zintl compounds with ultralow lattice thermal conductivity and good electrical conductivity. Understanding mechanisms for obtaining low thermal conductivity without degraded electrical properties remains a challenge. Here, the authors reveal a mechanism for thermal conductivity reduction in a Zintl phase thermoelectric based on length scales for disorder in Eu2ZnSb2.
TL;DR: This novel phenylboronic acid-based hydrogel MNP lays the foundation for fabrication of a sensitive, safe and stable transdermal drug delivery system.
TL;DR: Driven by the evolution of electronic packaging technology for high-dense integration of high-power, high-frequency, and multi-function devices in modern electronics, thermal management materials h...
Abstract: Driven by the evolution of electronic packaging technology for high-dense integration of high-power, high-frequency, and multi-function devices in modern electronics, thermal management materials h...
TL;DR: In this paper, the authors explore the acoustofluidic performance of zinc oxide (ZnO) thin-film surface acoustic wave (SAW) devices fabricated on flexible and bendable thin aluminum (Al) foils/sheets with thicknesses from 50 to 1500 μm.
Abstract: In this paper, we explore the acoustofluidic performance of zinc oxide (ZnO) thin-film surface acoustic wave (SAW) devices fabricated on flexible and bendable thin aluminum (Al) foils/sheets with thicknesses from 50 to 1500 μm. Directional transport of fluids along these flexible/bendable surfaces offers potential applications for the next generation of microfluidic systems, wearable biosensors and soft robotic control. Theoretical calculations indicate that bending under strain levels up to 3000 μe causes a small frequency shift and amplitude change (<0.3%) without degrading the acoustofluidic performance. Through systematic investigation of the effects of the Al sheet thickness on the microfluidic actuation performance for the bent devices, we identify the optimum thickness range to both maintain efficient microfluidic actuation and enable significant deformation of the substrate, providing a guide to design such devices. Finally, we demonstrate efficient liquid transportation across a wide range of substrate geometries including inclined, curved, vertical, inverted, and lateral positioned surfaces using a 200 μm thick Al sheet SAW device.
TL;DR: In this article, a glucose-responsive 4-carboxy-3-fluorophenylboronic acid-grafted e-polylysine (CFPBA-g-PL) was synthesized to meet the requirements.
Abstract: Microneedles with insulin-loaded glucose-responsive particles are promising to control the blood glucose levels of diabetic patients. In particular, the long-term usage of these microneedles calls for biodegradable and cost-effective particles, which are still large challenges. In this paper, glucose-responsive 4-carboxy-3-fluorophenylboronic acid-grafted e-polylysine (CFPBA-g-PL) was synthesized to meet these requirements. CFPBA-g-PL had low cytotoxicity, good hemocompatibility and no tissue reaction. The pharmacokinetics of CFPBA-g-PL were also studied. The self-assembled particles of CFPBA-g-PL were prepared via simple ultrasonic treatment. The insulin-loaded particles of CFPBA-g-PL (named INS/GRP-12.8) presented a glucose-responsive insulin delivery performance based on the disassembly-related mechanism in vitro. The INS/GRP-12.8-encapsulated microneedle patch with a uniform morphology and moderate skin penetration performance was prepared via a molding strategy. INS/GRP-12.8 lasted for more than 8 hours of normoglycemia on STZ-induced diabetic SD rats via subcutaneous injection and the INS/GRP-12.8-encapsulated microneedle patch also showed a blood-glucose-level-lowering performance in vivo via transdermal administration.
TL;DR: In this paper, the average grain size of the Mg3Sb2 was increased by 15 times and the grain boundary scattering was manipulated to obtain high carrier mobility of up to 180 cm2/V−1/s−1.
Abstract: Thermoelectric devices require thermoelectric materials with high figure-of-merit ( ZT ) values in the operating temperature range. In recent years, the Zintl phase compound, n-Mg3Sb2, has received much attention owing to its rich chemistry and structural complexity. However, it hardly achieves high ZT values throughout the medium temperature range. Herein, by increasing the sintering temperature as much as possible, we successfully increased the average grain size of the compound by 15 times, and the grain boundary scattering was manipulated to obtain high carrier mobility of up to 180 cm2 V−1 s−1. Simultaneously, we optimized the Mg content for ultralow lattice thermal conductivity. We first doped the Mg3Sb2-based materials with boron for higher sintering temperature, good thermal stability, and higher hardness. The synergistic optimization of electrical and thermal transport resulted in excellent ZT values (0.62 at 300 K, 1.81 at 773 K) and an average ZT of 1.4 (from 300 to 773 K), which are higher than the state-of-the-art values for n-type thermoelectric materials, demonstrating a high potential in device applications.
TL;DR: In this article, a quasioptical microcavity (QOM) structure was proposed to enhance the spectral selectivity and thermal stability of the absorber used in the concentrated solar power system.
Abstract: Enhancing the spectral selectivity and thermal stability of the absorber used in the concentrated solar power system would boom the conversion efficiency of solar energy to electricity. The ceramic coatings possess excellent thermal stability in optical films. Here, we design the ZrB2-based all-ceramic spectrally selective absorber with a quasioptical microcavity (QOM) structure, which shows an excellent performance with a solar absorptance of 0.965 and superior thermal stability. The pretty high absorptance is due to the design of QOM inducing the multiabsorption mechanisms composed of the intrinsic cermet absorption, the surface plasmon polaritons, and localized surface plasmon resonance proved by the electromagnetic power loss. The structure also demonstrates well-matched impedance with free space in the solar spectrum range, ensuring a high solar absorptance. The proposed absorber can survive at 800 °C in vacuum or 500 °C in air for 200 h, ascribed to the introduction of QOM and ultrahigh-temperature ceramic ZrB2. The total conversion efficiency of an ideal system with this absorber and an ideal thermal engineer can reach around 67% under the conditions of 800 °C and 1000 suns.
TL;DR: In this paper, a self-compensation method was proposed to suppress the "donor-like" effect caused by ball milling in Bi0.4Sb1.6Te3 materials, which leads to a high average zT value of 1.39 from 30 to 200 ℃.
TL;DR: In this paper, the authors take thermoelectric materials as a paradigm, illustrating how to interpret and utilize phase diagrams as well as other thermodynamic information to design target materials, with the aid of multi-component CALPHAD-base databases and software.
Abstract: Phase diagrams have always been used as a roadmap for materials research in terms of melting, casting, crystal growth, joining, solid-state reaction, heat treatment, phase transformation, and so on. CALPHAD (CALculation of PHAse Diagram) offers a theoretical instruction through a plausible simulation based on Gibbs energies, which could bypass some difficult experiments, extrapolate to a multicomponent-system or metastable region to get complete thermodynamic and kinetic properties, and improve the consistency and accuracy of the measured phase diagram. The present work takes thermoelectric materials as a paradigm, illustrating how to interpret and utilize phase diagrams as well as other thermodynamic information to design target materials, with the aid of multi-component CALPHAD-base databases and software. Two main aspects including phase design and microstructure modulation are delivered by the fundamentals of CALPHAD modeling and concrete examples of thermoelectric alloys. Opinions about the challenges and potentials of its applications in thermoelectric systems are also pointed out.
TL;DR: In this article, the authors demonstrate the safety and feasibility of NOSES and show that patients in the NOSE group had less intraoperative bleeding (49.3% vs. 57.6%, p = 0.02), lower postoperative pain scores, lower rate of postoperative complications (6.8% vs 25.4%), better satisfaction of the image and cosmesis of the abdominal wall postoperatively, and higher quality of life.
Abstract: Natural orifice specimen extraction surgery (NOSES) is an intra-abdominal procedure that does not require an auxiliary incision to take a surgical sample from the abdominal wall through the natural orifice, but there are few systematic clinical studies on it. The aim of this study was to demonstrate the safety and feasibility of NOSES. We retrospectively analyzed the clinical data and follow-up of 165 patients with low rectal cancer who underwent NOSES or conventional laparoscopic surgery at our center from January 2013 to June 2015. From the perioperative data and postoperative follow-up results of both groups, patients in the NOSES group had less intraoperative bleeding (49.3 ± 55.8 ml vs. 75.1 ± 57.3 ml, p = 0.02), shorter postoperative gastrointestinal recovery (42.3 ± 15.5 h vs. 50.1 ± 17.0 h, p = 0.01), less postoperative analgesic use (35.6% vs. 57.6%, p = 0.02), lower postoperative pain scores, lower rate of postoperative complications (6.8% vs. 25.4%, p = 0.01), better satisfaction of the image and cosmesis of the abdominal wall postoperatively, and higher quality of life. Moreover, there was no significant difference in overall survival (OS) and disease-free survival (DFS) between two groups. Overall, NOSES is a safe and reliable minimally invasive surgical technique for patients with low rectal cancer.
TL;DR: In this paper, the aptamer-exosome combination was analyzed for the diagnosis and prognosis of cancer using exosomes and aptamers, and future directions for the combination were proposed for personalized treatment of cancer.
Abstract: As carriers of biomolecules (proteins, nucleic acids, and lipids) from parent cells, exosomes play a significant role in physiology and pathology. In any diseased state, the morphology of the released exosomes remained similar. The contents of exosomes change depending on the disease or its stage; thus, exosomes are generally considered as a "source of biomarkers". Therefore, they are considered promising biomarkers for the diagnosis and prognosis of tumors. As natural delivery vehicles, exosomes can protect their cargo from immune clearance and deliver them to other cells through membrane fusion. After being genetically edited at the cell or exosome level, exosomes can be used for treatment with aptamers. Aptamers are short stretches of oligonucleotide sequences or short polypeptides that have been selected in vitro or in vivo, and have a wide range of targets and show excellent binding affinity and specificity. Aptamers have been widely used as molecular probes, and the combination of aptamers with exosomes has become a new direction for exosome-related research and therapeutic development. Here, we summarized various applications of exosomes and aptamers in cancer research, and further analyzed their combination as an "aptamer-exosome". Finally, we propose future directions for the aptamer-exosome in the precise diagnosis or personalized treatment of cancer.
TL;DR: In this paper, a cohort of 34 colorectal cancer patients (average age=65 years old), 26 young volunteers (below 30 years old) and 26 old volunteers (over 60 years old).
Abstract: Intestinal microbiota is gaining increasing interest from researchers, and a series of studies proved that gut bacteria plays a significant role in various malignancies, especially in colorectal cancer (CRC). In this study, a cohort of 34 CRC patients (average age=65 years old), 26 young volunteers (below 30 years old), and 26 old volunteers (over 60 years old) was enrolled. 16S ribosomal RNA gene sequencing was used to explore fecal bacteria diversity. The operational taxonomic unit (OTU) clustering analysis and NMDS (non-metric multidimensional scaling) analysis were used to separate different groups. Cluster of ortholog genes (COG) functional annotation and Kyoto encyclopedia of genes and genomes (KEGG) were used to detect enriched pathways among three groups. Community separations were observed among the three groups of this cohort. Clostridia, Actinobacteria, Bifidobacterium, and Fusobacteria were the most enriched bacteria in the young group, old group, and CRC group respectively. Also, in the young, old, and CRC group, the ratio of Firmicutes/Bacteroidetes was increased sequentially despite no statistical differences. Further, COG showed that transcription, cell wall/membrane/envelope biogenesis, inorganic ion transport and metabolism, and signal transduction mechanisms were differentially expressed among three groups. KEGG pathways associated with ABC transporters, amino sugar and nucleotide sugar metabolism, arginine and proline metabolism, and aminoacyl-tRNA biosynthesis also showed statistical differences among the three groups. These results indicated that the intestinal bacterial community varied as age changed and was related to CRC, and we discussed that specific bacteria enriched in the young and old group may exert a protective function, while bacteria enriched in the CRC group may promote tumorigenesis.
TL;DR: In this paper, a series of metal-organic complexes were synthesized and characterized under the assembly of electron donor phosphonate, electron acceptor polypyridine ligand and spin carrier rare earth ions.