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Manipulating the charge carrier transport in photoactive materials is a big challenge toward high efficiency solar water splitting. Herein, we designed a hierarchical ZnxCd1-xS architecture for tuning the interfacial charge transfer kinetics. RTA408 The in situ growth of ZnxCd1-xS nanoflakes on ZnO backbones provided low interfacial resistance for charge separation. With this special configuration, the optimized Zn0.33Cd0.67S photoanode achieved significantly enhanced performance with a photocurrent density of 10.67 mA cm-2 at 1.23 V versus RHE under AM1.5G solar light irradiation, which is about 14.1 and 2.5 times higher than that of the pristine ZnO and CdS nanoparticle decorated ZnO photoanodes, respectively. After coating a thin SiO2 layer, the photostability of the hierarchical Zn0.33Cd0.67S photoanode is greatly enhanced with 92.33% of the initial value retained under 3600 s continuous light illumination. The prominent PEC activity of the hierarchical ZnxCd1-xS nanorod arrays can be ascribed to an enhanced charge transfer rate aroused by the binder-free interfacial heterojunction, and the improved reaction kinetics at the electrode-electrolyte interface, which is evidenced by electrochemically active surface area measurements and intensity modulated photocurrent spectroscopy analysis. This interfacial heterojunction strategy provides a promising pathway to prepare high performance photoelectrodes.Many chemical and biological reactions, including ligand exchange processes, require thermal energy for the reactants to overcome a transition barrier and reach the product state. Temperature-jump (T-jump) spectroscopy uses a near-infrared (NIR) pulse to rapidly heat a sample, offering an approach for triggering these processes and directly accessing thermally-activated pathways. However, thermal activation inherently increases the disorder of the system under study and, as a consequence, can make quantitative interpretations of structural changes challenging. In this Article, we optimise a deep neural network (DNN) for the instantaneous prediction of Co K-edge X-ray absorption near-edge structure (XANES) spectra. We apply our DNN to analyse T-jump pump/X-ray probe data pertaining to the ligand exchange processes and solvation dynamics of Co2+ in chlorinated aqueous solution. Our analysis is greatly facilitated by machine learning, as our DNN is able to predict quickly and cost-effectively the XANES spectra of thousands of geometric configurations sampled from ab initio molecular dynamics (MD) using nothing more than the local geometric environment around the X-ray absorption site. We identify directly the structural changes following the T-jump, which are dominated by sample heating and a commensurate increase in the Debye-Waller factor.The multiple bonds between actinide atoms and their derivatives are computationally investigated extensively and compounds with an unsupported actinide-actinide bond, especially in low oxidation states, have attracted great attention. Herein, high level relativistic quantum chemical methods are used to probe the Ac-Ac bonding in compounds with a general formula LAcAcL (L = AsH3, PH3, NH3, H, CO, NO) at both scalar and spin-orbit coupling relativistic levels. H3AsAcAcAsH3, H3PAcAcPH3 and OCAcAcCO compounds show a type of zero valence Ac[triple bond, length as m-dash]Ac triple bond with a 1σ2g1π4u configuration, and H3AsAcAcAsH3 has been found to have the shortest Ac-Ac bond length of 3.012 Å reported so far. The Ac2 unit is very sensitive to the σ donor ligands and can form triple, double and even single bonds when suitable ligands are introduced, up to 3.652 Å with an Ac-Ac single bond in H3NAcAcNH3.Carbon nanotube (CNT) and perovskite composite materials possessing the combined advantages of CNTs and perovskites have drawn substantial attention due to their promising applications in photovoltaic and optoelectronic devices. Understanding the band alignment of heterojunctions is crucial for further performance improvement. Here, we systematically investigated the interfacial electronic structure and optical absorption of a semiconducting CNT/CH3NH3PbI3 heterojunction via density functional theory calculations. It was found that the CNT/PbI2-terminated CH3NH3PbI3 (001) surface heterojunction is a type-I band alignment, while the CNT/CH3NH3I-terminated CH3NH3PbI3 (001) surface heterojunction is a type-II band alignment, suggesting the different charge carrier transfer processes as well as termination dependence of band alignment in the CNT/CH3NH3PbI3 heterojunction. Further investigation indicated that applying electric fields can modify the band alignment type in the CNT/CH3NH3PbI3 heterojunction. Our results provide the first insight into the interfacial electronic structure of the CNT/CH3NH3PbI3 heterojunction, which may give a new route for designing optoelectronic devices.Cu2ZnGeSe4 (CZGSe) is a promising earth-abundant and non-toxic semiconductor material for large-scale thin-film solar cell applications. Herein, we have employed a joint computational and experimental approach to characterize and assess the structural, optoelectronic, and heterojunction band offset and alignment properties of a CZGSe solar absorber. The CZGSe films were successfully prepared using DC-sputtering and e-beam evaporation systems and confirmed by XRD and Raman spectroscopy analyses. The CZGSe films exhibit a bandgap of 1.35 eV, as estimated from electrochemical cyclic voltammetry (CV) measurements and validated by first-principles density functional theory (DFT) calculations, which predicts a bandgap of 1.38 eV. A fabricated device based on the CZGSe as a light absorber and CdS as a buffer layer yields power conversion efficiency (PCE) of 4.4% with VOC of 0.69 V, FF of 37.15, and Jsc of 17.12 mA cm-2. Therefore, we suggest that interface and band offset engineering represent promising approaches to improve the performance of CZGSe devices by predicting a type-II staggered band alignment with a small conduction band offset of 0.18 eV at the CZGSe/CdS interface.Uniting combinational strategies has been confirmed to be a robust choice for high-performance cancer treatment due to their abilities to overcome tumor heterogeneity and complexity. However, the development of a simple, effective, and multifunctional theranostics nanoplatform still remains a challenge. In this study, we integrated multicomponent hyaluronic acid (HA), protamine (PS), nanodiamonds (NDs), curcumin (Cur), and IR780 into a single nanoplatform (denoted as HPNDIC) based on the combination of hydrophobic and electrostatic noncovalent interactions for dual-modal fluorescence/photoacoustic imaging guided ternary collaborative Cur/photothermal/photodynamic combination therapy of triple-negative breast cancer (TNBC). A two-step coordination assembly strategy was utilized to realize this purpose. In the first step, PS was utilized to modify the NDs clusters to form positively charged PS@NDs (PND) and the simultaneous encapsulation of the natural small-molecule drug Cur and the photosensitive small-molecule IR780 (PNDIC). Second, HA was adsorbed onto the outer surface of the PNDIC through charge complexation for endowing a tumor-targeting ability (HPNDIC). The resulting HPNDIC had a uniform size, high drug-loading ability, and excellent colloidal stability. It was found that under the near-infrared irradiation condition, IR780 could be triggered to exhibit both PTT/PDT dual-pattern therapy effects, leading to an enhanced therapy efficiency of Cur both in vitro and in vivo with good biocompatibility. Due to the intrinsic imaging property of IR780, the biodistribution and accumulation behavior of HPNDIC in vivo could be monitored by dual-modal fluorescence/photoacoustic imaging. Taken together, our current work demonstrated the assembly of a NDs-based multicomponent theranostic platform for dual-modal fluorescence/photoacoustic imaging guided triple-collaborative Cur/photothermal/photodynamic against TNBC.Formamidinium lead iodide (FAPbI3) can be used in its cubic, black form as a light absorber material in single-junction solar cells. It has a band-gap (1.5 eV) close to the maximum of the Shockley-Queisser limit, and reveals a high absorption coefficient. Its high thermal stability up to 320 °C has also a downside, which is the instability of the photo-active form at room temperature (RT). Thus, the black α-phase transforms at RT with time into a yellow non-photo-active δ-phase. The black phase can be recovered by annealing of the yellow state. In this work, a polymorphism of the α-phase at room temperature was found as-synthesized (αi), degraded (αδ) and thermally recovered (αrec). They differ in the Raman spectra and PL signal, but not in the XRD patterns. Using temperature-dependent Raman spectroscopy, we identified a structural change in the αi-polymorph at ca. 110 °C. Above 110 °C, the FAPbI3 structure has undoubtedly cubic Pm3[combining macron]m symmetry (high-temperature phase αHT). Below that temperature, the αi-phase was suggested to have a distorted perovskite structure with Im3[combining macron] symmetry. Thermally recovered FAPbI3 (αrec) also demonstrated the structural transition to αHT at the same temperature (ca. 110 °C) during its heating. The understanding of hybrid perovskites may bring additional assets in the development of new and stable structures.The utilization of multivalent ions such as Ca(ii), Mg(ii), and Al(iii) in energy storage devices opens up new opportunities to store energy density in a more efficient manner rather than monovalent Li or Na ion batteries. Active research on Ca(ii) has been limited due to the low diffusion rate of Ca within the lattice as well as the difficulty of the reversible electrodeposition of Ca in standard electrolytes at room temperature. Herein, using first-principles calculations, we have studied the applications of various allotropes of phosphorene (Pn) as potential materials for Ca(ii) battery (CIB). It is seen that among different forms, α and δ phases are suitable to act as anode materials for Ca ion battery. Apart from this, we have also studied the possible formation of various CaxPy phases during the calcination process since it is assumed that during metal insertion and extraction, anodes form non-equilibrium structures. Evolutionary Structure Prediction methods are extensively utilized to determine if the formation of these different CaxPy phases have a significant impact on the anodic performances of Pn or not. It is found that the CaxPy phases formed during the calcination process show reasonable average voltages as well as low volume change and high specific capacity, thus confirming the suitability of Pn as an excellent support for anodes in the Ca(ii) ion battery.Two-dimensional graphene-like hexagonal borophene sheets (HBSs) have a thermodynamically unsteady configuration since boron has one electron less than the carbon in graphene. To overcome this problem, we proposed a novel 2D graphene-like HBS oxide (h-B3O) in theory, which is designed by substituting partial boron atoms in a HBS with oxygen atoms. Molecular dynamics simulations indicate that h-B3O has good thermal stability. Besides, we also explored the potential of h-B3O monolayers as anodes for Li-ion batteries (LIBs) and Na-ion batteries (NIBs) by using first-principles calculations. The results indicated that the h-B3O monolayer has high adsorption energies (-2.33/-1.70 eV for Li/Na), low diffusion barriers (0.67/0.42 eV for Li/Na) and suitable average open-circuit voltages (0.36/0.32 V for LIBs/NIBs). Particularly, h-B3O has a large theoretical specific capacity of 1161 mA h g-1 for LIBs. Thus, benefiting from these characteristics, the h-B3O monolayer is considered as a promising candidate for an anode material for LIBs/NIBs.

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