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Science Advances Jun 2024Short-wavelength infrared (SWIR) light detection plays a key role in modern technologies. Emerging solution-processed organic semiconductors are promising for...
Short-wavelength infrared (SWIR) light detection plays a key role in modern technologies. Emerging solution-processed organic semiconductors are promising for cost-effective, flexible, and large-area SWIR organic photodiodes (OPDs). However, the spectral responsivity () and specific detectivity (*) of SWIR OPDs are restricted by insufficient exciton dissociation and high noise current. In this work, we synthesized an SWIR small molecule with a spectral coverage of 0.3 to 1.3 micrometers peaking at 1100 nanometers. The photodiode, with optimized exciton dissociation, charge injection, and SWIR transmittance, achieves a record high of 0.53 ampere per watt and * of 1.71 × 10 Jones at 1110 nanometers under zero bias. The * at 1 to 1.2 micrometers surpasses that of the uncooled commercial InGaAs photodiode. Furthermore, large-area semitransparent all-organic upconversion devices integrating the SWIR photodiode realized static and dynamic SWIR-to-visible imaging, along with excellent upconversion efficiency and spatial resolution. This work provides alternative insights for developing sensitive organic SWIR detection.
PubMed: 38838154
DOI: 10.1126/sciadv.adm9631 -
ACS Applied Materials & Interfaces Jun 2024The Fe/FeCl-Graphite molten salt battery is a promising technology for large-scale energy storage, offering a long lifespan, a low operating temperature (<200 °C), and...
The Fe/FeCl-Graphite molten salt battery is a promising technology for large-scale energy storage, offering a long lifespan, a low operating temperature (<200 °C), and cost efficiency. However, its practical applications are hindered by the lack of a scalable preparation approach and insufficient redox stability in the Fe/FeCl electrode. Our study introduces an electrochemical anodic electrolysis (EAE) strategy, employing the anodic process (Fe → Fe) in an Al|AlCl/NaCl/LiCl|Fe electrolysis system for the Fe/Fe negative electrode in the Fe/FeCl-Graphite battery. The EAE strategy forms an oxidized film, preventing incipient dissolution in the electrolyte and addressing redox stability issues with FeCl as the active substance. The Fe/Fe negative electrode prepared by the EAE strategy exhibits a stabilized capacity of 0.72 mAh/cm after 7000 cycles at 5 mA/cm, with a lower polarization level (∼29 mV) compared to FeCl as the active component. The flexibility of the EAE strategy is validated in both galvanostatic and potentiostatic processes, with a discharge capacity of 14 mAh after 1000 cycles, a capacity retention rate of 85%, and a Coulombic efficiency of 98% in the potentiostatic anodic electrolysis Fe/Fe electrode. The scalability and reliability of the EAE strategy are further demonstrated in capacity-expanded Fe/FeCl-Graphite batteries, reaching a discharge capacity of 155.1 mAh after 1000 cycles at 130 mA, with a capacity retention rate of 94%. For the first time, we showcased an EAE approach capable of producing Fe/Fe electrodes at a rate of about 68.6 m per day. Additionally, we successfully assembled an Fe/FeCl-Graphite battery at about a 0.42 ampere-hour level, paving the way for the scalable application of Fe/FeCl-Graphite batteries.
PubMed: 38828906
DOI: 10.1021/acsami.4c03592 -
Journal of Colloid and Interface Science Oct 2024Promoting water dissociation and H intermediate desorption play a pivotal role in achieving highly efficient hydrogen evolution reaction (HER) in alkaline media but...
Promoting water dissociation and H intermediate desorption play a pivotal role in achieving highly efficient hydrogen evolution reaction (HER) in alkaline media but remain a great challenge. Herein, we rationally develop a unique W-doped NiS/Ni heterointerface as a favorable HER electrocatalyst which was directly grown on the Cu nanowire foam substrate (W-NiS/Ni@Cu) by the electrodeposition strategy. Benefiting from the rational design of the interfaces, the electronic coupling of the W-NiS/Ni@Cu can be efficiently modulated to lower the HER kinetic barrier. The obtained W-NiS/Ni@Cu exhibits an enhanced HER activity with a low overpotential of 38 mV at 10 mA cm and a small Tafel value of 27.5 mV dec, and high stability during HER catalysis. In addition, in-situ Raman spectra reveal that the Ni active sites preferentially adsorb OH intermediate. The theoretical calculation confirms that the water dissociation is accelerated by the construction of W-NiS/Ni heterointerface and H intermediate desorption can be also promoted by H spillover from S active sites in W-NiS to Ni active sites in metal Ni. This work offers a valuable reference for rational designing heterointerface of electrocatalysts and provides an available method to accelerate the HER kinetics for the ampere-level current density under low overpotential.
PubMed: 38815382
DOI: 10.1016/j.jcis.2024.05.182 -
Bioelectromagnetics May 2024Numerous studies have demonstrated the efficacy of extremely low frequency-pulsed electromagnetic fields (ELF-PEMF) in accelerating the wound healing process in vitro...
Numerous studies have demonstrated the efficacy of extremely low frequency-pulsed electromagnetic fields (ELF-PEMF) in accelerating the wound healing process in vitro and in vivo. Our study focuses specifically on ELF-PEMF applied with the Magnomega® device and aims to assess their effect during the main stages of the proliferative phase of dermal wound closure, in vitro. Thus, after the characterization of the EMFs delivered by the Magnomega® unit, primary culture of human dermal fibroblasts (HDFs) were exposed, or not for the control culture, to 10-12 and 100 Hz ELF-PEMF. These parameters are used in clinical practice by physiotherapists in order to enhance healing of dermal lesions in patients. HDFs proliferation was first assessed and revealed an increase in the expression of one of the two genetic markers of cell proliferation tested (PCNA and MKI67), after initial exposure of the cells to 10-12 Hz PEMF. Next, migration of HDFs was investigated by performing scratch assays on HDF layers. The observed wound closure kinetics corroborate the early organization of actin stress fibers that was revealed in the cytoplasm of HDFs exposed to 100 Hz ELF-PEMF. Also, maturation of HDFs into myofibroblasts was significantly increased in cells exposed to 10-12 or to 100 Hz PEMF. The present study is the first to demonstrate, in vitro, an early stimulation of HDFs, after their exposure to ELF-PEMF delivered by the Magnomega® device, which could contribute to an acceleration of the wound healing process.
PubMed: 38807301
DOI: 10.1002/bem.22508 -
Nanoscale Jun 2024With the rapid development of technology, the development of self-powered sensors has garnered significant attention. The importance of monitoring humidity has grown...
With the rapid development of technology, the development of self-powered sensors has garnered significant attention. The importance of monitoring humidity has grown significantly in various technological contexts, from environmental monitoring to biomedical applications. In this work, we have fabricated a low-cost and self-powered humidity sensor using zero-dimensional perovskite-like structures. Switching tests at different relative humidity levels have shown that the zero-dimensional perovskites have visible coloration at high humidities and discoloration upon reducing the humidity. The humidity sensor was fabricated by spin coating the zero-dimensional perovskites on a patterned fluorine doped tin oxide (FTO) substrate and the sensor not only shows high response values of around 500 mV and few micro amperes of short circuit current densities, but also shows good cycling performance and stability. Also high selectivity to humidity is observed in comparison to different gases and volatile organic compounds. The high selectivity to humidity arises due to the fact that the exclusion of MAI from the MAPbI strucuture does not happen with all the other analytes which has been confirmed from the XRD studies. In addition, due to the low temperature fabrication they can be deposited on flexible substrates and the sensor displayed excellent resistance to bending and durability. Furthermore, the study explored the humidity monitoring capabilities of this sensor, revealing an outstanding response performance to human respiration. This observation suggests that the sensor holds significant potential for practical applications in the monitoring of human health and environmental conditions. This work paves the way for developing organic-inorganic hybrid perovskite materials for self-powered sensing applications.
PubMed: 38804981
DOI: 10.1039/d4nr01065e -
Angewandte Chemie (International Ed. in... May 2024The practical application of the electrocatalytic CO2 reduction reaction (CO2RR) to form formic acid fuel is hindered by the limited activation of CO2 molecules and the...
The practical application of the electrocatalytic CO2 reduction reaction (CO2RR) to form formic acid fuel is hindered by the limited activation of CO2 molecules and the lack of universal feasibility across different pH levels. Herein, we report a doping-engineered bismuth sulfide pre-catalyst (BiS-1) that S is partially retained after electrochemical reconstruction into metallic Bi for CO2RR to formate/formic acid with ultrahigh performance across a wide pH range. The best BiS-1 maintains a Faraday efficiency (FE) of ~95% at 2000 mA cm-2 in a flow cell under neutral and alkaline solutions. Furthermore, the BiS-1 catalyst shows unprecedentedly high FE (~95%) with current densities from 100 to 1300 mA cm-2 under acidic solutions. Notably, the current density can reach 700 mA cm-2 while maintaining a FE of above 90% in a membrane electrode assembly electrolyzer and operate stably for 150 h at 200 mA cm-2. In-situspectra and density functional theory calculations reveals that the S doping modulates the electronic structure of Bi and effectively promotes the formation of the HCOO* intermediate for formate/formic acid generation. This work develops the efficient and stable electrocatalysts for sustainable formate/formic acid production.
PubMed: 38801019
DOI: 10.1002/anie.202408412 -
Small (Weinheim An Der Bergstrasse,... May 2024Direct electrolysis of seawater to generate hydrogen is an attractive approach for storing renewable energy. However, direct seawater splitting suffers from low current...
Direct electrolysis of seawater to generate hydrogen is an attractive approach for storing renewable energy. However, direct seawater splitting suffers from low current density and limited operating stability, which severely hinders its industrialization. Herein, a promising strategy is reported to obtain a nano needle-like array catalyst-CDs-Mn-CoP on nickel foam, in which the Mn─O─C bond tightly binds Mn, Carbon dots (CDs), and CoP together. The coordination engineering of CDs and Mn not only effectively regulates the electronic structure of CoP, but also endows the as-prepared catalyst with selectivity and marked long-term stability at ampere-level current density. Low overpotentials of 208 and 447 mV are required to achieve 1000 mA cm for hydrogen evolution reaction (HER) and Oxygen evolution reaction (OER) in simulated seawater, respectively. Cell potentials of 1.78 and 1.86 V are needed to reach 500 and 1000 mA cm in alkaline seawater along with excellent durability for 350 h. DFT studies have verified that the introduction of Mn and CDs effectively shifts the d-band center of Co-3d toward higher energy, thereby strengthening the adsorption of intermediates and enhancing the catalytic activity. This study sheds light on the development of highly effective and stable catalysts for large-scale seawater electrolysis.
PubMed: 38778729
DOI: 10.1002/smll.202402478 -
Small Methods May 20242D materials are intriguing due to their remarkably thin and flat structure. This unique configuration allows the majority of their constituent atoms to be accessible on... (Review)
Review
2D materials are intriguing due to their remarkably thin and flat structure. This unique configuration allows the majority of their constituent atoms to be accessible on the surface, facilitating easier electron tunneling while generating weak surface forces. To decipher the subtle signals inherent in these materials, the application of techniques that offer atomic resolution (horizontal) and sub-Angstrom (z-height vertical) sensitivity is crucial. Scanning probe microscopy (SPM) emerges as the quintessential tool in this regard, owing to its atomic-level spatial precision, ability to detect unitary charges, responsiveness to pico-newton-scale forces, and capability to discern pico-ampere currents. Furthermore, the versatility of SPM to operate under varying environmental conditions, such as different temperatures and in the presence of various gases or liquids, opens up the possibility of studying the stability and reactivity of 2D materials in situ. The characteristic flatness, surface accessibility, ultra-thinness, and weak signal strengths of 2D materials align perfectly with the capabilities of SPM technologies, enabling researchers to uncover the nuanced behaviors and properties of these advanced materials at the nanoscale and even the atomic scale.
PubMed: 38766949
DOI: 10.1002/smtd.202400211 -
ACS Omega May 2024Platinum nanoparticles loaded on a nitrogen-doped carbon nanotubes exhibit a brilliant hydrogen evolution reaction (HER) in an alkaline solution, but their bifunctional...
Platinum nanoparticles loaded on a nitrogen-doped carbon nanotubes exhibit a brilliant hydrogen evolution reaction (HER) in an alkaline solution, but their bifunctional hydrogen and oxygen evolution reaction (OER) has not been reported due to the lack of a strong Pt-C bond. In this work, platinum nanoparticles bonded in carbon nanotubes (Pt-NPs-bonded@CNT) with strong Pt-C bonds are designed toward ultralow overpotential water splitting ability in alkaline solution. Benefit from the strong interaction between platinum and high conductivity carbon nanotube substrates through the Pt-C bond also the platinum nanoparticles bonded in carbon nanotube can provide more stable active sites, as a result, the Pt-NPs-bonded@CNT exhibits excellent hydrogen evolution in acid and alkaline solution with ultralow overpotential of 0.19 and 0.23 V to reach 1000 mA cm, respectively. Besides, it shows superior oxygen evolution electrocatalysis in alkaline solution with a low overpotential of 1.69 V at 1000 mA cm. Furthermore, it also exhibits high stability over 110 h against the evolution of oxygen and hydrogen at 1000 mA cm. This strategy paves the way to the high performance of bifunctional electrocatalytic reaction with extraordinary stability originating from optimized electron density of metal active sites due to strong metal-substrate interaction.
PubMed: 38764639
DOI: 10.1021/acsomega.4c01662 -
Angewandte Chemie (International Ed. in... May 2024Efficient production of value-added chemicals with high selectivity from CO2 electroreduction at industrial-level current density is highly demanded, yet remains a big...
Efficient production of value-added chemicals with high selectivity from CO2 electroreduction at industrial-level current density is highly demanded, yet remains a big challenge. In a recent issue of Angewandte Chemie, Han and colleagues have elegantly increased the Faradaic efficiency (FE) of multi-carbon (C2+) products to over 70% at amperes level (1.4 A cm-2) by engineering the active sites for the key reactions involved in the CO2 electroreduction. In this study, the highly dispersed Pd atoms have two unique functions: active sites for water dissociation and to induce the electron rearrangement of the surrounding Cu atoms to form new active sites for CO conversion, while the Cu far from Pd are the active sites for efficient CO2 conversion to CO, the synergistic functions of these three active sites result in high FE and yields of C2+ products at industrial-level current density. This research is a remarkable step forward in the methodology for developing efficient and durable catalysts for CO2 electroreduction and beyond.
PubMed: 38757209
DOI: 10.1002/anie.202406879