MXenes have emerged as potential antimicrobial materials. Here, the authors report on the creation of a Schottky junction to increase the charge separation between MXenes and semiconductor to ...increase photodynamic creation of reactive oxygen species under near infrared irradiation for antibacterial purposes.
Abstract
In view of increasing drug resistance, ecofriendly photoelectrical materials are promising alternatives to antibiotics. Here we design an interfacial Schottky junction of Bi
2
S
3
/Ti
3
C
2
...T
x
resulting from the contact potential difference between Ti
3
C
2
T
x
and Bi
2
S
3
. The different work functions induce the formation of a local electrophilic/nucleophilic region. The self-driven charge transfer across the interface increases the local electron density on Ti
3
C
2
T
x
. The formed Schottky barrier inhibits the backflow of electrons and boosts the charge transfer and separation. The photocatalytic activity of Bi
2
S
3
/Ti
3
C
2
T
x
intensively improved the amount of reactive oxygen species under 808 nm near-infrared radiation. They kill 99.86% of
Staphylococcus aureus
and 99.92% of
Escherichia coli
with the assistance of hyperthermia within 10 min. We propose the theory of interfacial engineering based on work function and accordingly design the ecofriendly photoresponsive Schottky junction using two kinds of components with different work functions to effectively eradicate bacterial infection.
Magnetoelectric (ME) magnetic field sensors utilize ME effects in ferroelectric ferromagnetic layered heterostructures to convert magnetic signals into electrical signals. However, the substrate ...clamping effect greatly limits the design and fabrication of ME composites with high ME coefficients. To reduce the clamping effect and improve the ME response, a flexible ME sensor based on PbZr0.2Ti0.8O3 (PZT)/CoFe2O4 (CFO) ME bilayered heterostructure was deposited on mica substrates via van der Waals oxide heteroepitaxy. A saturated magnetization of 114.5 emu/cm3 was observed in the bilayers. The flexible sensor exhibited a strong ME coefficient of 6.12 V/cm·Oe. The local ME coupling has been confirmed by the evolution of the ferroelectric domain under applied magnetic fields. The flexible ME sensor possessed a stable response with high sensitivity to both AC and DC weak magnetic fields. A high linearity of 0.9988 and sensitivity of 72.65 mV/Oe of the ME sensor were obtained under flat states. The ME output and limit-of-detection under different bending states showed an inferior trend as the bending radius increased. A flexible proximity sensor has been demonstrated, indicating a promising avenue for wearable device applications and significantly broadening the potential application of the flexible ME magnetic field sensors.
Phase Conductance of BiFeO3 Film Wang, Yufeng; Zhou, Peng; Fetisov, Leonid ...
Sensors (Basel, Switzerland),
11/2023, Letnik:
23, Številka:
22
Journal Article
Recenzirano
Odprti dostop
In this work, the local conductance of the tetragonal-like (T-like) and rhombohedral-like (R-like) phases of epitaxial BiFeO3 film is systematically studied via conductive atomic force microscopy. At ...higher tip voltage, there is a mutual transition between the T-like and R-like phases, which could be attributed to the strain relaxation in the T-like phase induced by electric poling, as well as local polarization switching. The T-like phase exhibits a higher conductance, which is related to the lower interface potential barrier between the tip and film surface. Reversible low- and high-current states in the T-like phase can be tuned by polarization switching. These results will be helpful for designing novel nanoelectronic devices, such as voltage and strain sensors.
A morphotropic phase boundary driven by epitaxial strain has been observed in lead‐free multiferroic BiFeO3 thin films and the strain‐driven phase transitions have been widely reported as ...iso‐symmetric Cc‐Cc by recent works. In this paper, it is suggested that the tetragonal‐like BiFeO3 phase identified in epitaxial films on (001) LaAlO3 single crystal substrates is monoclinic MC. This MC phase is different from the MA type monoclinic phase reported in BiFeO3 films grown on low mismatch substrates, such as SrTiO3. This is confirmed not only by synchrotron X‐ray studies but also by piezoresponse force microscopy measurements. The polarization vectors of the tetragonal‐like phase lie in the (100) plane, not the (110) plane as previously reported. A phenomenological analysis is proposed to explain the formation of MC Phase. Such a low‐symmetry MC phase, with its linkage to MA phase and the multiphase coexistence open an avenue for large piezoelectric response in BiFeO3 films and shed light on a complete understanding of possible polarization rotation paths and enhanced multiferroicity in BiFeO3 films mediated by epitaxial strain. This work may also aid the understanding of developing new lead‐free strain‐driven morphotropic phase boundary in other ferroic systems.
Strain‐mediated polarization rotation for BiFeO3 films is shown in the figure. Starting from the strain‐free rhombohedral (R) phase, the strain‐induced transition path is R to Ma by compressive strains or R to Mb by tensile strains. At large enough compressive strains, the Ma to Mc phase transition occurs and brings about a sudden increase in the c‐lattice parameter. This new rotation path indicates a soft lattice for BiFeO3 and a tunable behavior by strains where the polarization rotation paths could be mediated in the same way as in those driven by electric field, chemical composition, pressure, and temperature.
In the recent few decades, the increase in multidrug-resistant (MDR) bacteria has reached an alarming rate and caused serious health problems. The incidence of infections due to MDR bacteria has been ...accompanied by morbidity and mortality; therefore, tackling bacterial resistance has become an urgent and unmet challenge to be properly addressed. The field of nanomedicine has the potential to design and develop efficient antimicrobials for MDR bacteria using its innovative and alternative approaches. The uniquely constructed nano-sized antimicrobials have a predominance over traditional antibiotics because their small size helps them in better interaction with bacterial cells. Moreover, surface engineering of nanocarriers offers significant advantages of targeting and modulating various resistance mechanisms, thus owe superior qualities for overcoming bacterial resistance. This review covers different mechanisms of antibiotic resistance, application of nanocarrier systems in drug delivery, functionalization of nanocarriers, application of functionalized nanocarriers for overcoming bacterial resistance, possible limitations of nanocarrier-based approach for antibacterial delivery, and future of surface-functionalized antimicrobial delivery systems.
Nowadays, wearable and flexible nanogenerators are of great importance for portable personal electronics. A flexible piezoelectric energy harvester (f-PEH) based on Bi3.15Nd0.85Ti3O12 single ...crystalline nanoplates (BNdT NPs) and polydimethylsiloxane (PDMS) elastomeric polymer was fabricated, and high piezoelectric energy harvesting performance was achieved. The piezoelectric output performance is highly dependent on the mass ratio of the BNdT NPs in the PDMS matrix. The as-prepared f-PEH with 12.5 wt% BNdT NPs presents the highest output voltage of 10 V, a peak-peak short-circuit current of 1 μA, and a power of 1.92 μW under tapping mode of 6.5 N at 2.7 Hz, which can light up four commercial light emitting diodes without the energy storage process. The f-PEHs can be used to harvest daily life energy and generate a voltage of 2–6 V in harvesting the mechanical energy of mouse clicking or foot stepping. These results demonstrate the potential application of the lead-free BNdT NPs based f-PEHs in powering wearable electronics
To identify inflamm-aging related biomarkers in osteoarthritis (OA).
Microarray gene profiles of young and aging OA patients were obtained from the Gene Expression Omnibus (GEO) database and ...aging-related genes (ARGs) were obtained from the Human Aging Genome Resource (HAGR) database. The differentially expressed genes of young OA and older OA patients were screened and then intersected with ARGs to obtain the aging-related genes of OA. Enrichment analysis was performed to reveal the potential mechanisms of aging-related markers in OA. Three machine learning methods were used to identify core senescence markers of OA and the receiver operating characteristic (ROC) curve was used to assess their diagnostic performance. Peripheral blood mononuclear cells were collected from clinical OA patients to verify the expression of senescence-associated secretory phenotype (SASP) factors and senescence markers.
A total of 45 senescence-related markers were obtained, which were mainly involved in the regulation of cellula
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