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The high toxicity, volatility, and dispersion of the light aromatics, benzene, toluene, and xylene (BTX) pose a serious threat to the environment and human health. Compared to incineration, catalytic oxidation technologies for BTX removal offer benefits such as low energy consumption, high efficiency, and low pollution. ABO3–type perovskite catalysts (ABO3–PCs) are particularly promising materials for the catalytic oxidation of BTX due to their high activity and thermal stability, as well as their adjustable elemental composition and flexible structure allowing their properties to be improved. Nonetheless, the full potential of ABO3–PCs for the oxidation of BTX has yet to be reached. This review systematically and critically analyses progress in the catalytic oxidation of BTX by ABO3–PCs. Catalytic performance is assessed for each category of perovskite, including non–doped, doped (A–, B–, or A/B–site doped), and loading type (noble metal, metal oxide, and matrix composite), with structure–activity relationships are established. A kinetic model and proposed mechanism for the catalytic oxidation of BTX are also presented. Finally, the challenges and opportunities of ABO3–PCs applied to BTX oxidation and other reactions are highlighted. [ABSTRACT FROM AUTHOR]

Following the 3rd release of the "Emerging PV reports", the best achievements in the performance of emerging photovoltaic (e‐PV) devices in diverse e‐PV research subjects are summarized, as reported in peer‐reviewed articles in academic journals since August 2022. Updated graphs, tables, and analyses are provided with several performance parameters, such as power conversion efficiency, open‐circuit voltage, short‐circuit current density, fill factor, light utilization efficiency, and stability test energy yield. These parameters are presented as a function of the photovoltaic bandgap energy and the average visible transmittance for each technology and application, and are put into perspective using, for example, the detailed balance efficiency limit. The 4th installment of the "Emerging PV reports" discusses the "PV emergence" classification with respect to the "PV technology generations" and "PV research waves" and highlights the latest device performance progress in multijunction and flexible photovoltaics. Additionally, Dale‐Scarpulla's plots of efficiency‐effort in terms of cumulative academic publication count are also introduced. [ABSTRACT FROM AUTHOR]

Following the 2nd release of the "Emerging PV reports," the best achievements in the performance of emerging photovoltaic devices in diverse emerging photovoltaic research subjects are summarized, as reported in peer‐reviewed articles in academic journals since August 2021. Updated graphs, tables, and analyses are provided with several performance parameters, e.g., power conversion efficiency, open‐circuit voltage, short‐circuit current density, fill factor, light utilization efficiency, and stability test energy yield. These parameters are presented as a function of the photovoltaic bandgap energy and the average visible transmittance for each technology and application, and are put into perspective using, e.g., the detailed balance efficiency limit. The 3rd installment of the "Emerging PV reports" extends the scope toward triple junction solar cells. [ABSTRACT FROM AUTHOR]

Following pioneering work (1), solution-processable organic-inorganic hybrid perovskites--such as C[H.sub.3]N[H.sub.3]Pb[X.sub.3] (X = Cl, Br, I)--have attracted attention as light-harvesting materials for mesoscopic solar cells (2-15). So far, the perovskite pigment has been deposited in a single step onto mesoporous metal oxide films using a mixture of Pb[X.sub.2] and C[H.sub.3]N[H.sub.3]X in a common solvent. However, the uncontrolled precipitation of the perovskite produces large morphological variations, resulting in a wide spread of photovoltaic performance in the resulting devices, which hampers the prospects for practical applications. Here we describe a sequential deposition method for the formation of the perovskite pigment within the porous metal oxide film. Pb[I.sub.2] is first introduced from solution into a nanoporous titanium dioxide film and subsequently transformed into the perovskite by exposing it to a solution of C[H.sub.3]N[H.sub.3]I. We find that the conversion occurs within the nanoporous host as soon as the two components come into contact, permitting much better control over the perovskite morphology than is possible with the previously employed route. Using this technique for the fabrication of solid-state mesoscopic solar cells greatly increases the reproducibility of their performance and allows us to achieve a power conversion efficiency of approximately 15 per cent (measured under standard AM1.5G test conditions on solar zenith angle, solar light intensity and cell temperature). This two-step method should provide new opportunities for the fabrication of solution-processed photovoltaic cells with unprecedented power conversion efficiencies and high stability equal to or even greater than those of today's best thin-film photovoltaic devices., We prepared mesoporous Ti[O.sub.2] (anatase) films by spin-coating a solution of colloidal anatase particles onto a 30-nm-thick compact Ti[O.sub.2] underlayer. The underlayer was deposited by aerosol spray pyrolysis on a [...]

It presents a combined experimental and computational study of several ruthenium(II) sensitizers originated from the [Ru(dcbpyH(sub 2))(sub 2)(NCS)(sub 2)], N3, and [Ru(dcbpyH(sub 2))(tdbpy)(NCS)(sub 2)], N621, (dcbpyH(sub 2) = 4,4'-dicaboxy-2,2'-bipyridine, tdbpy = 4,4'-tridecyl-2,2'-bipyridine) complexes, an extensive Density Functional Theory (DFT)-Time Dependent DFT study of these sensitizers in solution was performed. Obtained theoretical result on the role of protnation in the interacting dye-semiconductor systems is in progress.

Author(s): Mohammad K. Nazeeruddin (corresponding author) [1] About 85% of the world's energy requirements are currently satisfied by exhaustible fossil fuels that have detrimental consequences on human health and the [...]

Perovskite solar cells have garnered and held international research interest, due to ever‐climbing power conversion efficiency values, now >25 %. Some high efficiency configurations utilize a compact TiO2 layer underneath a mesoporous TiO2 layer, both of which require high temperature annealing steps that could hinder perovskite commercialization. To address the high thermal budget, we chose to use inkjet‐printing to combine the two layers into a single TiO2 film, which incorporates both nanoparticle and molecular precursor as well as organic fullerene additives. We printed the ink on fluorine‐doped tin oxide, and after annealing at various temperatures, we found that 400 °C was the optimum annealing temperature for the inkjet‐printed electron transport layers, which is significantly lower than the 500 °C required to anneal typical mesoporous TiO2 films. [ABSTRACT FROM AUTHOR]

A novel thiocyanate-free cyclometalated ruthenium sensitizer is designed and developed for solar cells. The results have shown that the HOMO is located on ruthenium and cyclometalated ligand, while the LUMO is on 4-carboxylic acid-4'-carboxylate-2,2'-bipyridine.

The synthesis and characterization of highly phosphorescent blue-light-emitting anionic iridium complexes are described. Density functional theory (DFT) and time dependent-DFT calculations are performed on the ground and excited states of these complexes in order to provide insights into the structural electronic and optical properties of these systems.

The article discusses the importance of the protonation of the sensitizer on the excited states of the Ru(II)-sensitized Ti[O.sub.2] nanoparticles. The protonation is found to highly affect the Ti[O.sub.2] positioning in these particles.

The synthesis, electronic and photovoltaic properties of the squaraine sensitizer are described. It is shown that creating directionality and inhibiting self-quenching of the excited state of the sensitizer is the key for unprecedented efficiency of squaraines.

The effect of nanoparticle morphology and interfacial modification on the performance of hybrid polymer/zinc oxide photovoltaic devices is reported. A photovoltaic device based on the nanorod structure that was treated with an amphiphilic dye before deposition of the poly-3-hexylthiophene (P3HT) polymer yields a power conversion efficiency over four times greater than that for a similar device based on the nanoparticle structure.

The selective functionalization of a ruthenium complex, resulting in red-shifted absorption spectra and enhanced molar extinction coefficient of the sensitizer is demonstrated. The finding allows creation of directionality in the excited state of sensitizer by adjusting the electron densities of the donor moieties that are not attached to the TiO(sub 2) surface.

A series of novel intense green porphyrins containing carboxylate anchoring groups are shown to have potential as light sensitizers in TiO(sub 2) solar cells. Density function theory (DFT) and time-dependent DFT calculations have shown that presence of electron-withdrawing moieties on the substituent modulates the electronic absorption spectrum through stabilization of the energies of the lowest occupied orbital (LUMO) and LUMO + 2.

A series of D‐(π‐A)2 organic dyes with different π spacers have been designed and synthesized. The modification of the bi‐anchoring dyes regarding π spacers assists in tuning the photochemical and electrochemical properties of the dyes, which determine the open circuit voltage (VOC), short circuit current density (JSC) and hence overall power conversion efficiency. It is found that varying the spacers has more influence on determining the short circuit current density of the solar cell devices made with these sensitizers. When thiophene is used as π spacer, higher short circuit current density of 9.42 mA/cm2 is observed. The better IPCE of the dye with thiophene as spacer further supports its advantage over other spacers. The observed tunable light harvesting property, electrochemical and photovoltaic behaviour by varying the π spacers in D‐(π‐A)2 type sensitizers will provide fruitful information for future designing of sensitizers with multi‐anchoring modes. [ABSTRACT FROM AUTHOR]

Methods for effective synthesis for the four possible isomeric 3,9-diphenylullazine carboxaldehydes and reactive halogen intermediates are described. Ullazine donor-acceptor (D-A) dyes were studied using UV/Vis, photoluminescence (PL) spectroscopy and cyclic voltammetry. X-ray single crystal diffraction analysis independently confirmed the structures of two key intermediates. A D-A dye based on ullazine with dihexylmalonate acceptor was tested as a dopant-free hole-transporting material (HTM) in a perovskite solar cell, exhibiting promising power conversion efficiency (PCE) reaching 13.07 %. [ABSTRACT FROM AUTHOR]

Research into phosphorescent Ir(III) complexes has grown immensely since their first report. Talented chemists have successfully synthesized complexes capable of emitting from the ultraviolet to the near-infrared regions of the electromagnetic spectrum. Tuning the emission energy in a selective manner requires knowledge of how ligand substitution affects not only energy levels such as the highest occupied molecular orbital and lowest unoccupied molecular orbital, but also the emissive triplet energy level. This review describes fundamental principles involved in energy-level engineering and substituent selection as well as fundamental methods of device characterization. [ABSTRACT FROM AUTHOR]

To date β-aryloxy-substituted designs have led to the best results in phthalocyanine-sensitized solar cells (Pc-SCs) because of their low aggregation properties. By incorporating the bulky semiflexible 2,6-diphenylphenoxy group at three α-positions of the Pc, different regioisomers were separated by column chromatography and their photovoltaic performance was thoroughly studied. Efficiencies in the range of 1.9-4.1 % were found, thus demonstrating the importance of the steric interaction between the substituents and the semiconductor surface, also in the case of bulky semiflexible substituents. It was discovered that regioisomers which presented greater steric hindrance around the anchoring group, had lower adsorption densities, and, consequently, lower short-circuit photocurrents ( Jsc) and efficiencies. [ABSTRACT FROM AUTHOR]

Impressive hybrid photovoltaic device performances have been realised with the methylammonium lead triiodide (MAPbI3) perovskite absorber in a wide range of device architectures. However, the question as to which of these systems represents the most commercially viable long-term prospect is yet to be answered conclusively. Here, we report on the photoinduced charge transfer processes in MAPbI3 based films measured under inert and ambient conditions. When exposed to ambient conditions, the coated mesoporous Al2O3 and bilayer systems show a rapid and significant degradation in the yield of long-lived charge separation. This process, which does not affect sensitized-mesoporous TiO2 films, is only found to occur when both light and oxygen are present. These observations indicate that the presence of a mesostructured TiO2 electron acceptor to rapidly extract the photoexcited electron from the perovskite sensitizer may be crucial for fundamental photovoltaic stability and significantly increases innate tolerance to environmental conditions. This work highlights a significant advantage of retaining mesoscale morphological control in the design of perovskite photovoltaics. [ABSTRACT FROM AUTHOR]

Strong electron-donating functionality is desirable for many organic donor-π-bridge-acceptor (D-π-A) dyes. Strategies for increasing the electron-donating strength of common nitrogen-based donors include planarization of nitrogen substituents and the use of low resonance-stabilized energy aromatic ring-substituted nitrogen atoms. Organic donor motifs based on the planar nitrogen containing heterocycle indolizine are synthesized and incorporated into dye-sensitized solar cell (DSC) sensitizers. Resonance active substitutions at several positions on indolizine in conjugation with the D-π-A π-system are examined computationally and experimentally. The indolizine-based donors are observed to contribute electron density with strengths greater than triarylamines and diarylamines, as evidenced by UV/Vis, IR absorptions, and oxidation potential measurements. Fluorescence lifetime studies in solution and on TiO2 yield insights in understanding the performance of indolizine-based dyes in DSC devices. [ABSTRACT FROM AUTHOR]