Successive Energy Transfer Research Articles

Designing a model for enhancing intention to accept renewable energy technologies in rural communities of Ilam province, Iran

Purpose The purpose of this research is to investigate factors influencing the intention of villagers to use renewable energy. In this regard, by using the modified model of planned behavior, perceived behavioral control factors, perceived usefulness, perceived ease, mental norm and attitude toward energy sources for the intention of villagers to use energy sources. Therefore, the impact of each of these five variables was investigated in the form of research hypotheses. Design/methodology/approach This research has been done using a quantitative paradigm and a descriptive-correlation method. The statistical population of the study consisted of households (384) living in rural areas of Ilam province. A multistage cluster method was used to select the sample size. The data collection tool was a researcher-made questionnaire that was developed based on the research background and research problem. Face validity of the research tool by professors of Islamic Azad University of Ilam and construct validity and reliability of research tools were confirmed by Cronbach’s alpha coefficient and composite reliability. Data were analyzed statistically using SPSS26 and SmartPLS3 software. Findings The results showed that the intention to use renewable energies (REs) among the rural peoples of Ilam province is affected by factors such as mental norms, attitude, perceived usefulness and perceived behavioral control and there is a positive and significant relationship between them. Originality/value In Iran, there is a lot of potential for usage of RE in rural communities, but compared to fossil fuels, had a small share in the current energy supply (Rezaei et al., 2022). RE technologies have not been sufficiently accepted and used by Iranian rural people (Rezaei and Ghafranfarid, 2018). Se the public acceptance of RE technologies is vital for successful process energy transfer (Huijts et al., 2012), non-acceptance of RE by society is a major obstacle to establishing RE technologies in Iran (Savari and Razmavar, 2022). It is expected that this research will fill the gap in the research literature.

Achieving Cross Time-Domain Multiplexed Signal Cascade and Cancer Exosomes Identification by Bridging Long Lifetime Phosphor to NIR-II Lanthanide Energy Transfer.

Designing lanthanide luminescence lifetime sensors in the second near-infrared (NIR-II) window holds great potentials for physiological studies. However, the single lifetime signal is confined to one or two orders of magnitude of signal variation, which limits the sensitivity of lifetime probes. In this study, a lifetime cascade system, i.e., ZGO:Mn, Eu-DNA-1/TCPP-PEI70K@Yb-AptEpCAM, with a variety of signals (τm, τn, τµ, τm/τn and τm/τµ) is constructed for exosome identification using time-domain multiplexing. The sensitized ligand TCPP acts as both target-modulated switch and a bridge for connecting long lifetime ZGO:Mn, Eu-DNA-1 emitter to lanthanide Yb3+. This drives successive dual-path energy transfer and forms two D(donor)-A(acceptor) pairs. The lifetime variation is dominantly modulated by arranging TCPP as energy intermediate relay to covert milliseconds to nanoseconds to microseconds. It enables a broad lifetime range of six orders of magnitude. The presence of exosome specifically recognizes aptamers on TCPP-PEI70K@Yb-AptEpCAM to impede D-A pairs and reverse multiplexed response signals of the lifetime cascade system. The ratio lifetime signals τm/τn and τm/τµ achieve prominent exosome quantification and exosome type differentiation attributed to signal amplification. The cascade system relying on lifetime criteria can realize precise quantization and provide an effective strategy for subsequent physiological study.

Photocatalytic Dehydrogenative 6π‐Photocyclisation of Indole Derivatives via Successive Energy Transfer

AbstractHerein, a successive energy transfer (sEnT) strategy to enable a dehydrogenative 6π‐photocyclisation, without the need for an external oxidant is reported, in which the energetically unfavourable dehydrogenation is driven by energy transfer. The valuable applicability of this method was demonstrated by the scaffold hopping of indole containing bioactive molecules, as well as by the succinct synthesis of naturally occurring tetracyclic furocarbazole alkaloids. Moreover, experimental and computational studies were conducted to elucidate the reaction mechanism.

Plasmon effect on triplet-singlet energy transfer in the dye-doped Langmuir-Blodgett films

The effect of silver plasmonic nanoparticles on triplet-singlet energy transfer in the donor-acceptor pair of organic dyes was studied. Layered dye films were prepared on the surface of glass and island silver films using the Langmuir-Blodgett method. Amphiphilic analogs of Rose bengal and polymethine dye were used as donor and acceptor of energy. A polymer monolayer was deposited between monolayers of donor and acceptor molecules to exclude the competing triplet-triplet energy transfer. The spectra of delayed fluorescence and phosphorescence of donor-acceptor films and the delayed luminescence lifetime of donor in these films have been measured. It is shown that a threefold increase in the fluorescence intensity and a twofold increase in the donor phosphorescence intensity are observed on silver island films. The successful triplet-singlet energy transfer is evidenced by both the quenching of donor centers and appearance of sensitized delayed fluorescence of the acceptor with the duration close to the donor triplet lifetime. In the presence of silver nanoparticles, in addition to enhancement in the intensity of the donor emission, an increase in the efficiency of tripletsinglet energy transfer was observed. The obtained results can be used in various optical devices.

Boosting the Upconversion and Near‐Infrared Emission via Alloying Bi3+ in Cs2NaErCl6 Double Perovskite

AbstractRecently, lanthanide‐doped halide perovskites have attracted increasing attention due to their unique optical properties, such as upconversion (UC) and near‐infrared (NIR) emission. However, these emitters suffer from low efficiency, limiting further practical applications. Herein, a Bi3+‐alloyed double perovskite, Cs2NaEr0.5Bi0.5Cl6, with strong NIR‐triggered UC and NIR‐II (1000–1700 nm) emission is reported. Cs2NaEr0.5Bi0.5Cl6 exhibits efficient green UC emission with a high quantum yield up to 2.1% and NIR‐II emission peaking at 1541 nm with a quantum yield of 37.9% under 980 nm excitation. The strong UC emission is related with the efficient energy transfer between Er3+ and self‐trapped exciton states induced by corporation of Bi3+ ions. In addition, Bi3+ ions can act as diluters, suppressing the energy loss caused by undesirable successive energy transfer among Er3+ ions, enhancing the UC and NIR‐II emission. Furthermore, a water‐resistant Cs2NaEr0.5Bi0.5Cl6/polydimethylsiloxane film is prepared. Excitingly, Cs2NaEr0.5Bi0.5Cl6 not only shows the potential as a UC thermometry with high sensitivity but also exhibits a high signal to noise ratio in NIR imaging.

Intelligent Reflecting Surface assisted RF Energy Harvesting Mobile Edge Computing NOMA Networks: Performance Analysis and Optimization

In this paper, we focus on the performance analysis and optimization of an RF energy harvesting (EH) mobile edge computing (MEC) network by the assistance of the intelligent reflecting surface (IRS) and non-orthogonal multiple access (NOMA) schemes. Specifically, a pair of users harvest RF energy from a hybrid access point (HAP) and offloads their tasks to the MEC server at HAP through wireless links by employing an IRS-aided and uplink NOMA scheme. To evaluate the performance of this proposed system, the closed-form expressions of successful computation and energy transfer efficiency probabilities are derived. We further formulate a multi-objective optimization problem and propose an algorithm to find the optimal energy harvesting time switching ratio value to achieve the best performance, namely SENSGA-II. Moreover, the impacts of the network parameters are provided to draw helpful insight into the system performance. Finally, the Monte-Carlo simulation results are shown to confirm the correctness of our analysis. The results have shown that the deployment of IRS can improve the performance of this considered RF EH NOMA system by increasing the number of reflecting elements.

Synthesis, photophysical properties and theoretical evaluation of alkyl-linked porphyrin – BODIPY dyads

Novel porphyrin-BODIPY Dyads linked by alkyl chains of different lengths as molecular conjugates were prepared and their intramolecular energy transfer properties have been investigated. Steady-state absorption and emission spectra have shown the successful intramolecular energy transfer (FRET) from BODIPY to porphyrin units approved with the calculated Förster radii and FRET efficiencies. Alkyl chain shortening has revealed an explicit increase in energy transfer as it could be expected. Further, DFT and TD-DFT studies for the synthesized dyads were carried out and frontier molecular orbital energies were investigated at the HSEH1PBE/6-31+G** theory level. Strongly electron-withdrawing C6F5- substituents on the porphyrin periphery extended the HOMO-LUMO gap in contrast to the 4-CF3C6H4- substituent from ca. 2.37 eV to ca. 2.50 eV. Open-circuit voltage values (Voc), reorganization energies (λe and λh), ionization potentials, and adiabatic electron affinities were calculated to evaluate the optical and electronic behaviors of Dyads. Calculated Voc values exceeding 1.00 V, and low reorganization energies of the Dyads indicate that they are promising structures for developing new photovoltaics.

Upconversion Luminescent Humidity Sensors Based on Lanthanide-Doped MOFs

Lanthanide-doped metal-organic frameworks (Y/Yb/Er-MOF) were synthesized by a low-cost solvothermal method. The obtained Y/Yb/Er-MOF shows the cooperative upconversion luminescence of Yb3+ and upconversion luminescence of Er3+ (Yb3+-sensitized) irradiated by a continuous wave 980 nm laser. In order to explore the potential application of Y/Yb/Er-MOF in relative humidity (RH) sensors, the RH responsiveness of Y/Yb/Er-MOF was investigated by measuring the intensity changes of upconversion luminescence. The Y/Yb/Er-MOF possesses two luminescence centers, in which Yb3+ forms emission at 500 nm through the cooperative luminescence effect, and Er3+ achieves 660 nm emission through excited state absorption and successive energy transfer from Yb3+. Hence, the ratio meter luminescence sensor for RH is constructed based on Y/Yb/Er-MOF. The results show that the response of Y/Yb/Er-MOF to RH presents a linear relationship in the range of 11–95%. The cycle stability of Y/Yb/Er-MOF responses to RH was investigated with the intensity changes of upconversion luminescence, and the recovery ratio was more than 93% each time. Therefore, the Y/Yb/Er-MOF is a humidity-sensitive material with great potential for applications such as humidity sensors.

Impact of the Microwave Coupling Structure on an Electron-Cyclotron Resonance Thruster

The electron-cyclotron resonance thruster with magnetic nozzle relies on two successive energy transfer processes: first from electromagnetic energy to electron thermal energy, facilitated by a coupling structure; and second from electron thermal energy to ion directed kinetic energy, facilitated by a diverging magnetic field. The nature and geometry of the coupling structure are crucial to the first energy transfer process. This paper presents an experimental study of the performance of an electron-cyclotron resonance thruster with magnetic nozzle, equipped either with a waveguide-coupling structure or with a coaxial-coupling structure. The necessity of thrust balance measurements to perform such a comparison is demonstrated. The low coupling efficiency from microwave power to the plasma achieved by waveguide coupling is found to result in very large uncertainty with respect to the deposited power. A method to significantly reduce this uncertainty is proposed and implemented. Thrust balance measurements indicate for the coaxial-coupled thruster and for the waveguide-coupled thruster, both operated at 25 W of deposited microwave power and a mass flow rate of of xenon. Electrostatic probe measurements reveal that this difference can be explained by a difference in ion energy. The results emphasize the critical role of the coupling structure, which may have been previously overlooked.

NIR‐I/III afterglow induced by energy transfers between Er and Cr codoped in ZGGO nanoparticles for potential bioimaging

AbstractHerein, Cr3+ and Er3+ codoped zinc gallogermanate (ZGGO) nanoparticles with average size of ~60 nm was synthesized via a hydrothermal path. It was found that near infrared (NIR)‐III (~1540 nm) afterglow was realized in ZGGO:Cr3+,Er3+ nanoparticles based on the successive energy transfer (ET) from Cr3+ to Er3+ after the stoppage of low‐dose (60 mSv) X‐ray irradiation. Meanwhile, the upconverted afterglow at 696 nm was produced via the ET from Er3+ to Cr3+ under different NIR light (808, 980, and 1532 nm) irradiations. Our results demonstrated that an X‐ray pre‐irradiation and a subsequent 980‐nm light re‐excitation might be a good strategy for realizing potential bioimaging. In particular, local‐tissue NIR‐I afterglow imaging using Cr3+ and Er3+ codoped ZGGO nanoparticles can be easily acquired by one‐step 980‐nm laser radiation. Furthermore, NIR‐I/III afterglow mechanisms of ZGGO:Cr3+,Er3+ nanoparticles after stopping X‐ray or different NIR lights (808, 980, and 1532 nm) irradiations were given.

Performance Analysis of Multi User Mimo System With Successive Hybrid Information and Energy Transfer Beamformer

The current proliferation of communication networks such as MU-MIMO necessitates high throughput coupled with high data rates. For maximization of harvested power the power received must be increased. However, this causes an increase in interference adversely affecting the sum rate. It is imperative to work out the trade-off between energy harvesting and spectral efficiency which is directly related to the sum rate. This paper proposes the logic of optimization by the weighted coefficient method using successive hybrid information and energy transfer (SHIET) so that a trade-off can be achieved. As the multi-objective optimization seems to be more difficult, this is modified to a single-objective optimization using weight factor method. This method calculates channel state information (CSI) from the angle of perfectness which directly gives the sum rate. Further harvested power is calculated from achievable sum rate and truth value is determined by various weight coefficient factors. Simulation is carried out on MU-MIMO system for ascertaining the effectiveness of the proposed method for achieving an optimized trade-off between energy harvesting and spectral efficiency. The performance of trade-off is better with linear beamformers that employs ZF and MRT with a smaller number of information users, whereas the performance of SHIET outperforms when compared to the linear beamformers irrespective of any number of information users.

Tunable and white up-conversion emission from Tm3+-Ho3+-Yb3+/-Nd3+ co-doped GdVO4 phosphors under 808-nm excitation

Lanthanide-doped system with adjustable multicolor and white up-conversion (UC) emission has been developed in GdVO4 (GVO): Tm3+-Ho3+-Yb3+/-Nd3+ phosphors, which are fabricated via a facile solid-state reaction. Herein, we study their phase structures and the Ho3+ concentration effect on their up-conversion emission. Under 980 nm excitation, the Tm3+-Ho3+-Yb3+ tri-doped GVO phosphors exhibit intense luminescence combined with red, green and blue (RGB) emission and the successive energy transfer between Tm3+-Ho3+-Yb3+ ions causes a slight shift in the color coordinates of samples with different doping concentrations. Under 808 nm excitation, the color coordinate of the optimum GVO: Tm3+-Ho3+-Yb3+-Nd3+ phosphor is located at (0.3277, 0.3433), which is closest to the ideal white light emission corresponding to (0.3333, 0.3333). Therefore, it is proved that these phosphors provide potential applications in the fields of displays, lasers and optical telecommunication.

Study on the Emission Property in Ce3+, Tb3+, and Eu3+ Co-doped CaHfO3 Phosphors via Successive Energy Transfer

We investigated the energy transfer among three rare-earth ions, Ce3+, Tb3+, and Eu3+, and the related emission properties in a host material CaHfO3 by using photoluminescence spectroscopy. We found that in case of the Tb3+ and Eu3+ doubly-doped CaHfO3, the visible emission intensity of Eu3+ could be activated with the photoexcitation of the transitions in Tb3+ through an energy transfer from Tb3+ to Eu3+. By adding Ce3+ ions to this doubly doped sample, we obtained the Eu3+ emission with near-ultraviolet (NUV) light excitation in Ce3+ via the successive energy transfers Ce3+ → Tb3+ and Tb3+ → Eu3+. We observed that the emission colors were tuned from blue to green/yellow and then to red with NUV photoexcitation in Ce3+/Tb3+/Eu3+-codoped CaHfO3.

Synthesis of NIR Emitting Rare Earth Doped Fluorapatite Nanoparticles for Bioimaging Applications

Aim: To synthesize biocompatible nanoparticles of FAp co-doped with Yb/Er and Nd/Yb for bioimaging applications. Methods: Yb/Er FAp and Nd/Yb FAp was synthesized using microwave assisted wet precipitation and hydrothermal method respectively. Trisodium citrate was used as an organic modifier for the synthesis and then subjected to heat treatment for optical activation. For optical studies, Yb/Er FAp system was excited at 980 nm and Nd/Yb FAp at 800 nm. Results: In the case of Nd/Yb FAp the host matrix absorption and emission was observed, hence Nd/Yb was synthesized without citrate. On heat treatment of this for optical activation studies, when the Yb3+ concentration was increased to 10 mol%, the YbPO4 secondary phase was found to appear. Although, the Yb/Er FAp system resulted in large grain growth, no such grain growth was observed in Nd/Yb FAp and the grains were within the nano size regime even after heat treatment. Conclusion: Both the systems showed successful energy transfer from sensitizer to activator with a quantum yield of 74% for Yb/Er FAp and energy transfer efficiency of 71% for Nd/Yb FAp system. Both the samples were found to be cytocompatible and has the potential for using as probes for bioimaging applications.

Sensitization of upconverting nanoparticles with a NIR-emissive cyanine dye using a micellar encapsulation approach

Photon upconversion nanomaterials have a wide range of applications, including biosensing and deep-tissue imaging. Their typically very weak and narrow absorption bands together with their size dependent luminescence efficiency can limit their application potential. This has been addressed by increasingly sophisticated core–shell particle architectures including the sensitization with organic dyes that strongly absorb in the near infrared (NIR). In this work, we present a simple water-dispersible micellar system that features energy transfer from the novel NIR excitable dye, 1859 SL with a high molar absorption coefficient and a moderate fluorescence quantum yield to oleate-capped NaYF4:20%Yb(III), 2%Er(III) upconversion nanoparticles (UCNP) upon 808 nm excitation. The micelles were formed using the surfactants Pluronic F-127 and Tween 80 to produce a hydrophilic dye-UCNP system. Successful energy transfer from the dye to the UCNP could be confirmed by emission measurements that revealed the occurrence of upconversion emission upon excitation at 808 nm and an enhancement of the green Er(III) emission compared to direct Er(III) excitation at 808 nm.

Enhancing the energy transfer from Mn4+ to Yb3+ via a Nd3+ bridge role in Ca3La2W2O12:Mn4+,Nd3+,Yb3+ phosphors for spectral conversion of c-Si solar cells

In this work, a series of Mn4+, Nd3+ and Yb3+ singly and co-doped Ca3La2W2O12 (CLWO) phosphors were prepared using a high-temperature solid-state reaction approach. In CLWO:0.016Mn4+, the emission spectrum presents a band around 709 nm attributed to Mn4+2Eg→4A2g transition under 365 nm UV excitation, which partly overlaps the excitation spectrum of Nd3+ singly doped CLWO phosphors. This indicates that a non-radiative resonant energy transfer process from Mn4+ to Nd3+ ions would like to take place in Mn4+, Nd3+ co-doped CLWO phosphors. Although scarce spectral overlap between Mn4+ emission and Yb3+ excitation in respective singly CLWO samples is observed, the energy transfer from Mn4+ to Yb3+ ions can also be deduced based on the analyses of excitation spectra, emission spectra and decay times in Mn4+, Yb3+ co-doped CLWO materials, which is proposed to be a phonon-assisted energy transfer process since the energy difference between Mn4+ lowest excited state 2Eg and Yb3+ excited state 2F5/2 is quite large. Moreover, in Nd3+, Yb3+ co-doped CLWO, the energy transfer phenomenon from Nd3+ to Yb3+ ions can be also observed. Therefore, we introduce Nd3+ ions into Mn4+, Yb3+ co-doped CLWO phosphors to realize the Mn4+→Nd3+→Yb3+ successive energy transfer process. Based on this, the Yb3+ emission intensity is highly enhanced in Mn4+, Nd3+ and Yb3+ tri-doped CLWO relative to Mn4+, Yb3+ co-doped CLWO. As a result, with the assistance of two channels Mn4+→Nd3+→Yb3+ and Mn4+→Yb3+ energy transfer processes, the broadband UV/blue light from sunlight spectrum can be effectively converted into Yb3+ near infrared (NIR), matching with the excellent spectral response of solar cells, which is highly expected to improve the c-Si solar cells spectral conversion efficiency.

Domino-like multi-emissions across red and near infrared from solid-state 2-/2,6-aryl substituted BODIPY dyes

Considerable achievements on multiple emission capabilities and tunable wavelengths have been obtained in inorganic luminescent materials. However, the development of organic counterparts remains a grand challenge. Herein we report a series of 2-/2,6-aryl substituted boron-dipyrromethene dyes with wide-range and multi-fluorescence emissions across red and near infrared in their aggregation states. Experimental data of X-ray diffraction, UV–vis absorption, and room temperature fluorescence spectra have proved the multiple excitation and easy-adjustable emission features in aggregated boron-dipyrromethene dyes. Temperature-dependent and time-resolved fluorescence studies have indicated a successive energy transfer from high to step-wisely lower-located energy levels that correspond to different excitation states of aggregates. Consistent quantum chemical calculation results have proposed possible aggregation modes of boron-dipyrromethene dyes to further support the above-described scenario. Thus, this study greatly enriches the fundamental recognition of conventional boron-dipyrromethene dyes by illustrating the relationships between multiple emission behaviors and the aggregation states of boron-dipyrromethene molecules.

Successive energy transfer within multiple photosensitizers assembled in a hexameric hemoprotein scaffold

An assembly of multiple photosensitizers is demonstrated by development of a hexameric hemoprotein (HTHP) scaffold as a light harvesting model to replicate the successive energy transfer occuring within photosensitizer assemblies of natural systems. In our model, six zinc protoporphyrin IX (ZnPP) molecules are arrayed at the heme binding site of HTHP by supramolecular interactions and five fluorescein (Flu) molecules and one Texas Red (Tex) molecule as donor and acceptor photosensitizers, respectively, are attached to the HTHP protein surface with covalent linkages. The flow of excited energy from photoexcited Flu to Tex occurs via two pathways: direct energy transfer from Flu to Tex (path 1) and energy transfer via ZnPP (path 2). Steady state and time-resolved fluorescence measurements reveal that the energy transfer ratio of these pathways (path 1 : path 2) is 39 : 61. These findings indicate that the excited energy originating at five Flu and six ZnPP molecules is collected at one Tex molecule as a funnel-like bottom for light harvesting. The present system using the hexameric hemoprotein scaffold is a promising candidate for construction of an artificial light harvesting system having multiple photosensitizers to promote efficient use of solar energy.

"Super-Reducing" Photocatalysis: Consecutive Energy and Electron Transfers with Polycyclic Aromatic Hydrocarbons.

Donation welcome: Recent developments in visible-light photocatalysis allow the utilization of increasingly negative reduction potentials. Successive energy and electron transfer with polycyclic aromatic hydrocarbons enables the catalytic formation of strongly reducing arene radical anions, classical stoichiometric reagents for one-electron reduction in organic synthesis.

Engineering water-tolerant core/shell upconversion nanoparticles for optical temperature sensing.

Luminescence thermometry is a promising approach using upconversion nanoparticles (UCNPs) with a nanoscale regime in biological tissues. UCNPs are superior to conventional fluorescent markers, benefiting from their autofluorescence suppression and deep imaging in tissues. However, they are still limited by poor water solubility and weak upconversion luminescence intensity, especially at a small particle size. Recently, YVO4:Er+3,Yb+3 nanoparticles have shown high efficiency upconversion (UC) luminescence in water at single-particle level and high contrast imaging in biological models. Typically, a 980-nm laser triggers the UC process in the UCNPs, which overlaps with maximum absorption of water molecules that are dominant in biological samples, resulting in biological tissues overheating and possible damaging. Interestingly, neodymium (Nd+3) possesses a large absorption cross section at the water low absorption band (808nm), which can overcome overheating issues. In this Letter, we introduce Nd+3 as a new near-infrared absorber and UC sensitizer into YVO4:Er+3,Yb+3 nanoparticles in a core/shell structure to ensure successive energy transfer between the new UC sensitizer (Nd+3) to the upconverting activator (Er+3). Finally, we synthesized water-tolerant YVO4:Er+3,Yb+3@Nd+3 core/shell nanoparticles (average size 20nm) with strong UC luminescence at a biocompatible excitation wavelength for optical temperature sensing where overheating in water is minimized.