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The combination analysis of the valence XPS, C KAplha XES, and AES for the allotropes by deMon DFT calculations is demostrated using the model adamantane derivative (C10H12(CH3)(sub 4)), pyrene (C16H10) and C60 molecules respectively. The theoretical valence photoelectron, C KAlpha X-ray emission, and Auger electron spectra for the allotropes are in good accordance with the experimental ones.

Since carbon (C) atom has a variety of chemical bonds via hybridization between s and p atomic orbitals, it is well known that there are robust carbon materials. In particular, discovery of C 60 has been an epoch making to cultivate nanocarbon fields. Since then, nanocarbon materials such as nanotube and graphene have been reported. It is interesting to note that C 60 is soluble and volatile unlike nanotube and graphene. This indicates that C 60 film is easy to be produced on any kinds of substrates, which is advantage for device fabrication. In particular, electron-/photo-induced C 60 polymerization finally results in formation of one-dimensional (1D) metallic peanut-shaped and 2D dumbbell-shaped semiconducting C 60 polymers, respectively. This enables us to control the physicochemical properties of C 60 films using electron-/photo-lithography techniques. In this review, we focused on the structures, fundamental properties, and potential applications of the low-dimensional C 60 polymers and other nanocarbons such as C 60 peapods, wavy-structured graphene, and penta-nanotubes with topological defects. We hope this review will provide new insights for producing new novel nanocarbon materials and inspire broad readers to cultivate new further research in carbon materials., Competing Interests: The authors declare no potential conflict of interest., (© 2024 The Author(s). Published by National Institute for Materials Science in partnership with Taylor & Francis Group.)

Lead phthalocyanine (PbPc) is well known to be used as a good near-infrared (NIR) light absorber for organic solar cells (OSCs) and photodetectors. The monoclinic and triclinic phases have been understood to absorb the visible and NIR regions, respectively, so far. In the present study, we demonstrated from the absorption spectra and theoretical analysis that the visible band considerably originates from not only the monoclinic but also the amorphous and triclinic phases, and revealed the exciton dynamics in the PbPc film from static/time-resolved photoluminescence (PL), which are first reported. By comparing the external quantum efficiency between PbPc- and ZnPc-based OSCs in relation to their structure, morphology, and optical (absorption and PL) characteristics, we unraveled the reasons behind the PbPc film used as a good absorber for NIR-sensitive devices., (© 2022. The Author(s).)

We have examined the uptake mechanisms of platinum-group-metals (PGMs) and molybdenum (Mo) ions into Prussian blue nanoparticles (PBNPs) in a nitric acid solution for 24-h sorption test, using inductively coupled plasma atomic emission spectroscopy, powder XRD, and UV-Vis-NIR spectroscopy in combination with first-principles calculations, and revealed that the Ru 4+ and Pd 2+ ions are incorporated into PBNPs by substitution with Fe 3+ and Fe 2+ ions of the PB framework, respectively, whereas the Rh 3+ ion is incorporated into PBNPs by substitution mainly with Fe 3+ and minorly with Fe 2+ ion, and Mo 6+ ion is incorporated into PBNPs by substitution with both Fe 2+ and Fe 3+ ions, with maintaining the crystal structure before and after the sorption test. Assuming that the amount of Fe elusion is equal to that of PGMs/Mo substitution, the substitution efficiency is estimated to be 39.0% for Ru, 47.8% for Rh, 87% for Pd, and 17.1% for Mo 6+ . This implies that 0.13 g of Ru, 0.16 g of Rh, 0.30 g of Pd, and 0.107 g of Mo can be recovered by using 1 g PBNPs with a chemical form of KFe(III)[Fe(II)(CN) 6 ]., (© 2022. The Author(s).)

The active material of optoelectronic devices must accommodate for contacts which serve to collect or inject the charge carriers. It is the purpose of this work to find out to which extent properties of organic optoelectronic layers change close to metal contacts compared to known properties of bulk materials. Bottom-up fabrication capabilities of model interfaces under ultrahigh vacuum and single-atom low temperature (LT)-STM spectroscopy with density functional theory (DFT) calculations are used to detect the spatial modifications of electronic states such as frontier-orbitals at interfaces. The system under consideration is made of a silver substrate covered with a blend of C 60 and ZnPc molecules of a few monolayers. When C 60 and ZnPc are separately adsorbed on Ag(111), they show distinct spectroscopic features in STM. However, when C 60 is added to the ZnPc monolayer, it shows scanning tunneling spectra similar to ZnPc, revealing a strong interaction of C 60 with the ZnPc induced by the substrate. DFT calculations on a model complex confirm the strong hybridization of C 60 with ZnPc layer upon adsorption on Ag(111), thus highlighting the role of boundary layers where the donor-acceptor character is strongly perturbed. The calculation also reveals a significant charge transfer from the Ag to the complex that is likely responsible for a downward shift of the molecular LUMO in agreement with the experiment.

We have investigated the uptake mechanism of palladium (Pd: one of the most important elements in industry used as a catalyst) ions into Prussian-blue nanoparticles (PBNPs) in a nitric acid solution via high-resolution electron transmission microscopy, inductively coupled plasma atomic emission spectroscopy, powder X-ray diffraction, and ultraviolet-visible-near infrared spectroscopy in combination with first principles calculations. Comparison of the structural and electronic properties of PBNPs between before and after a 24 h sorption test reveals that the Pd 2+ ions incorporated into PBNPs by the substitution of Fe 2+ ions of the PB framework while maintaining the crystal structure, and the substitution efficiency is estimated to be 87% per PB unit cell. This implies that 0.30 g of Pd can be recovered by using 1 g of PB having the chemical formula KFe(iii)[Fe(ii)(CN) 6 ]. The present finding suggests that PB (or its analogues) can be applied to recycle noble and rare metals from electronic and nuclear wastes., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Hetero-junction organic photovoltaic (OPV) cells consisting of donor (D) and acceptor (A) layers have been regarded as next-generation PV cells, because of their fascinating advantages, such as lightweight, low fabrication cost, resource free, and flexibility, when compared to those of conventional PV cells based on silicon and semiconductor compounds. However, the power conversion efficiency (η) of the OPV cells has been still around 8%, though more than 10% efficiency has been required for their practical use. To fully optimize these OPV cells, it is necessary that the low mobility of carriers/excitons in the OPV cells and the open circuit voltage (V OC), of which origin has not been understood well, should be improved. In this review, we address an improvement of the mobility of carriers/excitons by controlling the crystal structure of a donor layer and address how to increase the V OC for zinc octaethylporphyrin [Zn(OEP)]/C60 hetero-junction OPV cells [ITO/Zn(OEP)/C60/Al]. It was found that crystallization of Zn(OEP) films increases the number of inter-molecular charge transfer (IMCT) excitons and enlarges the mobility of carriers and IMCT excitons, thus significantly improving the external quantum efficiency (EQE) under illumination of the photoabsorption band due to the IMCT excitons. Conversely, charge accumulation of photo-generated carriers in the vicinity of the donor/acceptor (D/A) interface was found to play a key role in determining the V OC for the OPV cells.

Fullerene polymers made of C(60) are systematically investigated by means of a first-principles pseudopotential approach within the local density approximation of the density functional theory. We assume 10 different structures of fullerene polymers. The first three are C(60) polymer networks cross-linked by [2+2] cycloadditional four-membered rings, and the other seven are composed of peanut-shaped fused C(60) polymer chains cross-linked by either seven-membered rings or eight-membered rings. Owing to the overlap of wave functions as well as the hybrid networks of sp(2)-like (3-fold coordinated) and sp(3)-like (4-fold coordinated) carbon atoms, the electronic structure is considerably different from each other. We find that the resulting electronic structure is either semiconductor or semimetal depending on the spatial dimensionality of materials.