Hydrogels are investigated broadly in flexible sensors which have been applied into wearable electronics. However, further application of hydrogels is restricted by the ambiguity of the sensing ...mechanisms, and the multi-functionalization of flexible sensing systems based on hydrogels in terms of cost, difficulty in integration, and device fabrication remains a challenge, obstructing the specific application scenarios. Herein, cost-effective, structure-specialized and scenario-applicable 3D printing of direct ink writing (DIW) technology fabricated two-dimensional (2D) transition metal carbides (MXenes) bonded hydrogel sensor with excellent strain and temperature sensing performance is developed. Gauge factor (GF) of 5.7 (0 - 191% strain) and high temperature sensitivity (-5.27% °C
) within wide working range (0 - 80 °C) can be achieved. In particular, the corresponding mechanisms are clarified based on finite element analysis and the first use of in situ temperature-dependent Raman technology for hydrogels, and the printed sensor can realize precise temperature indication of shape memory solar array hinge.
Perovskite variants have attracted wide interest because of the lead-free nature and strong self-trapped exciton (STE) emission. Divalent Sn(II) in CsSnX
3
perovskites is easily oxidized to ...tetravalent Sn(IV), and the resulted Cs
2
SnCl
6
vacancy-ordered perovskite variant exhibits poor photoluminescence property although it has a direct band gap. Controllable doping is an effective strategy to regulate the optical properties of Cs
2
SnX
6
. Herein, combining the first principles calculation and spectral analysis, we attempted to understand the luminescence mechanism of Te
4+
-doped Cs
2
SnCl
6
lead-free perovskite variants. The chemical potential and defect formation energy are calculated to confirm theoretically the feasible substitutability of tetravalent Te
4+
ions in Cs
2
SnCl
6
lattices for the Sn-site. Through analysis of the absorption, emission/excitation, and time-resolved photoluminescence (PL) spectroscopy, the intense green-yellow emission in Te
4+
:Cs
2
SnCl
6
was considered to originate from the triplet Te(IV) ion
3
P
1
→
1
S
0
STE recombination. Temperature-dependent PL spectra demonstrated the strong electron-phonon coupling that inducing an evident lattice distortion to produce STEs. We further calculated the electronic band structure and molecular orbital levels to reveal the underlying photophysical process. These results will shed light on the doping modulated luminescence properties in stable lead-free Cs
2
MX
6
vacancy-ordered perovskite variants and be helpful to understand the optical properties and physical processes of doped perovskite variants.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
CsPbX3 perovskites have attracted tremendous attention recently due to their excellent optical properties and potential applications. However, this seemingly counterintuitive fact that CsPbX3 ...perovskites can act as both extraordinary photovoltaic materials and superior emission mediums has not yet been well understood. In this work, the absorption spectrum, temperature-dependent Raman spectra, temperature- and excitation power-dependent steady-state micro-photoluminescence along with the temperature-dependent emission lifetime dynamics were used to characterize systematically the luminescence processes of solution-grown CsPbBr3 micro/nanowires with weak confinement. A dominative in situ triplet exciton emission at 527 nm with strong exciton–phonon coupling and a series of end-facet cavity-related emission bands in the range of 535–580 nm due to robust exciton–photon coupling were observed simultaneously in individual nanowires. The in situ triplet exciton luminescence shows an abnormal blue shift with increasing temperature, while the end-facet emission bands exhibit a red shift. The exciton binding energy and exciton–phonon coupling energy were extracted to be 57 and 66 meV, respectively, confirming the strong exciton–phonon coupling. Our results could provide new insight into the long-standing issue of intrinsic excitonic properties as well as the photophysical process and exciton–phonon/exciton–photon coupling in CsPbBr3 micro/nanostructures, which are critical and helpful to the development of high-performance optoelectronic devices.
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IJS, KILJ, NUK, PNG, UL, UM
High-quality Sn(IV)-doped CdS nanowires were synthesized by a thermal evaporation route. Both XRD and Raman scattering spectrum confirmed the doping effect. The room temperature photoluminescence ...(PL) demonstrated that both near bandgap emission and discrete trapped-state emission appeared simultaneously and significantly, which were attributed to the strong exciton trapping by impurities and electron–phonon coupling during the light transportation. The PL intensity ratio of near bandgap emission to trapped-state emission could be tune via doped Sn(IV) concentration in the CdS nanowires. It is interesting that the trapped-state emission shows well separated peaks with the assistance of 1LO, 2LO, 4LO phonons, demonstrating the boosting electron–phonon coupling in these doped CdS nanowires. The influence of Sn(IV) dopant is further revealed by PL lifetime decay profile. The optical micro-cavity also plays an important role on this emission process. Our results will be helpful to the understanding of doping modulated carrier interaction, trapping and recombination in one-dimensional (1D) nanostructures.
Written for industrial and academic researchers and development scientists in the life sciences industry, Bioprocessing Technology for Production of Biopharmaceuticals and Bioproducts is a guide to ...the tools, approaches, and useful developments in bioprocessing. This important guide: • Summarizes state-of-the-art bioprocessing methods and reviews applications in life science industries • Includes illustrative case studies that review six milestone bio-products • Discuses a wide selection of host strain types and disruptive bioprocess technologies
BiTe has been widely used as thermoelectric material. Here the BiTe nanotubes were synthesized by solvothermal method for the first time. The BiTe nanotubes were characterized via scanning electron ...microscope (SEM), X-ray diffraction (XRD) as well as transmission electron microscope (TEM), indicating the high crystal qualities of as-prepared products. The lattice dynamics of BiTe nanotubes was further studied via the micro-Raman scattering spectra in the temperature range of 103-593 K. Both the peak position and mode width of 2Ag1, 1Eg1 exhibit an obvious change with decreased temperature. All the Eg1, A1g1, Eg2, A1g2 modes have ultralow temperature coefficients of 1.85 × 10−5, 1.98 × 10−4, 1.09 × 10−4, 2.34 × 10−4 cm−1/K, respectively, which should be beneficial for obtaining high figure of merit (ZT) and confirm the outstanding thermoelectric performance of BiTe nanotubes.
Photoelectrochemical (PEC) water splitting into hydrogen and oxygen using hybridized semiconductor photoelectrodes has become a promising strategy for converting solar energy into clean and ...sustainable H
2
fuel. Here, we report a promising hybrid photoanode constructed by electrodepositing an amorphous Co–Pi film onto semiconducting CdSe/TiO
2
nanowire arrays for photoelectrochemical hydrogen production. This photoanode exhibits a high water-splitting photocurrent density, which is attributed to the broad visible light absorption and efficient charge carrier separation by the virtue of the type-II heterojunction formed between TiO
2
and CdSe. Photoconversion efficiency of Co–Pi/CdSe/TiO
2
and CdSe/TiO
2
photoanodes increase by 3.3 and 2.1 times, compared with the pristine TiO
2
photoanode. Moreover, Co–Pi/CdSe/TiO
2
photoelectrode shows greatly improved PEC stability, the drop in photocurrent of Co–Pi/CdSe/TiO
2
nanowire arrays photoelectrode is about 10% after 1 h illumination, because of the addition of the Co–Pi film protecting the light absorber CdSe/TiO
2
from photocorrosion. The enhanced PEC performance mechanism of triple hybrid photoanode is also discussed in this paper.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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