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Herein, we report the synthesis, characterization, and photophysical properties of the crown-like structure of [3]cyclo-1,8-pyrenes (compounds 9 and 10). Planar pyrenyl arylene-ethynylene macrocycles are used as the precursors to synthesize these pyrene-based cycloarenes by [4 + 2] cycloaddition reaction with good yields. These molecules are confirmed by nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry. The structure of 9 was unambiguously determined by single-crystal X-ray diffraction. Their photophysical properties are investigated by steady-state absorption, fluorescence, and time-resolved fluorescence spectroscopies, combined with theoretical calculations.

Herein, we design and synthesize a novel all-carbon supramolecular polymer host (SPh) containing conjugated macrocycles interconnected by a linear poly(para-phenylene) backbone. Applying the supramolecular host and fullerene C60 as the guest, we successfully construct a supramolecular polymeric heterojunction (SPh⊃C60). This carbon structure offers a means to explore the convex–concave π–π interactions between SPh and C60. The produced SPh was characterized by gel permeation chromatography, mass spectrometry, FTIR, Raman spectroscopy, and other spectroscopies. The polymeric segment can be directly viewed using a scanning tunneling microscope. Femtosecond transient absorption and fluorescence up-conversion measurements revealed femtosecond (≪300 fs) electron transfer from photoexcited SPh to C60, followed by nanosecond charge recombination to produce the C60 triplet excited state. The potential applications of SPh⊃C60 in electron- and hole-transport devices were also investigated, revealing that C60 incorporation enhances the charge transport properties of SPh. These results expand the scope of the synthesis and application of supramolecular polymeric heterojunctions., Herein, we design and synthesize a novel all-carbon supramolecular polymer host (SPh) containing conjugated macrocycles interconnected by a linear poly(para-phenylene) backbone.

The total synthesis of carbon onions is a significant challenge in the fields of materials science and organic chemistry. To date, the synthesis of even a fragment of fullerene C240 and its smallest carbon onion C60@C240 remains poorly explored. Herein, we demonstrate a bottom-up strategy to produce a novel π-extended molecular crown-shaped molecule (MC3) containing curved pentagonal and hexagonal units. This molecular crown represents a curved model compound for fullerene C240 and is fully characterized by NMR, mass spectrometry, UV-vis absorption, and from its emission spectra. Its supramolecular host–guest interaction with fullerene C60 is also investigated. MC3 and C60@MC3 can potentially be employed as seeds or templates for the bottom-up synthesis of fullerene C240 and the carbon onion C60@C240, respectively.

Conjugated polymers have attracted much attention for many years and have applications in various organic devices. Carbon nanotubes can be considered as all-carbon tube-shaped conjugated polymers c...

The physical properties of conjugated cycloparaphenylene-based materials highly depend on their sizes, geometries, and functional groups. Herein we reported a facile strategy to synthesize novel multifunctionalized octamethoxy-[8]cycloparaphenylene (OMe-[8]CPP). Remarkably, an unusual hypsochromic shift in the emission spectrum was observed compared to its unfunctionalized nanoring. In addition, the photoinduced electron transfer process between OMe-[8]CPP and a naphthalene diimide electron acceptor is studied for the first time. OMe-[8]CPP will provide a suitable platform for subsequent synthesis manipulations to construct interesting and unprecedented functional nanocarbon structures.

Organic solar cells are an interesting and promising photovoltaic technology which has faced a strong development in the last decade. Still, there is plenty of room for device improvement. Many different parameters, not always easy to control, determine the final power conversion efficiency. In this work we analyze the impact of unbalance charge carrier mobilities. It is known that a different charge mobility for electrons and holes determines a reduction in performance. We have developed a numerical model that includes the 3D morphology of the blend in the simulator. With this model we are able to observe the charge and current density distribution across the blend at different working points. We have investigated the effect of charge unbalance to solar cell performance.

Cycloparaphenylenes (CPPs) and their analogs have recently attracted much attention due to their aesthetical structures and optoelectronic properties with radial π-conjugation systems. The past 10 years have witnessed a remarkable advancement in CPPs research, from synthetic methodology to optoelectronic investigations. In this present minireview, we highlight the supramolecular chemistry of CPPs and their analogs, mainly focusing on the size-selective encapsulation of fullerenes, endohedral metallofullerenes, and small molecules by these hoop-shaped macrocycles. We will also discuss the assembly of molecular bearings using some belt-persistent tubular cycloarylene molecules and fullerenes, photoinduced electron transfer properties in supramolecular systems containing carbon nanohoop hosts and fullerene guests, as well as the shape recognition properties for structure self-sorting by using dumbbell-shaped dimer of [60]fullerene ligand. Besides, the supramolecular complexes with guest molecules other than fullerenes, such as CPPs themselves, iodine, pyridinium cations, and bowl-shaped corannulene, are also discussed.

Herein, we explore phenanthrene as the building block to synthesize a hoop-shaped [6,6]carbon nanotube segment from a planar macocycle via a Diels-Alder reaction. The phenanthrene-based coronal nanohoop

The conventional Kalman filter (KF) which uses the current measurement to estimate the current state is a posterior estimation. KF is identified as the optimal estimation in linear models with Gaussian noise. However, the performance of KF with incomplete information may be degraded or diverged. In order to improve the performance of KF, an Amended KF (AKF) is proposed by using more posterior measurements. The principle, derivation and recursive process of AKF are presented. The differences among Kalman smoother, adaptive fading method and AKF are analyzed. The simulation results of target tracking with different covariance of motion model indicate the high precision and robustness of AKF.

Herein, we report a facile method of direct photodissociation of toluene molecules to photoluminescent carbon dots (CDs) under pulsed laser irradiation in the absence of surfactants or catalysts. The as-synthesized CDs with diameters 1.3–4.0 nm present regular emission peaks and the crystallographic structure of these species has been identified as graphite 2H from the analysis of high resolution transmission electron microscope (HRTEM) images, X-ray photoelectron spectroscopy (XPS) and Raman spectrum. In addition, First-Principle calculations were performed to discuss the photon-induced excitation in the photodissociation process. The results demonstrate that electrons can be transited from Highest Occupied Molecular Orbital (HOMO) to Lowest Unoccupied Molecular Orbital (LUMO) in toluene molecule by 248 nm single photon excitation process and the Stark effect plays a crucial role in the photodissociation process. These CDs exhibit excellent stable emission due to the stability of crystal structure, which could be considered for promising luminescent applications.

Photovoltaics is amongst the most important technologies for renewable energy sources, and plays a key role in the development of a society with a smaller environmental footprint. Key parameters for solar cells are their energy conversion efficiency, their operating lifetime, and the cost of the energy obtained from a photovoltaic system compared to other sources. The optimization of these aspects involves the exploitation of new materials and development of novel solar cell concepts and designs. Both theoretical modeling and characterization of such devices require a comprehensive view including all scales from the atomic to the macroscopic and industrial scale. The different length scales of the electronic and optical degrees of freedoms specifically lead to an intrinsic need for multiscale simulation, which is accentuated in many advanced photovoltaics concepts including nanostructured regions. Therefore, multiscale modeling has found particular interest in the photovoltaics community, as a tool to advance the field beyond its current limits. In this article, we review the field of multiscale techniques applied to photovoltaics, and we discuss opportunities and remaining challenges. © T. Abu Hamed et al., published by EDP Sciences, 2018., European Cooperation in Science and Technology: MP1406, The authors are grateful for the financial support by the COST Action MP1406 “MultiscaleSolar.”

A novel type of aqueous fluorescent carbon dot (CD) was synthesized using citric acid as the only carbon source via an ammonium hydroxide modulated method, providing a blue color gamut. The amino group is considered to be the key factor in the high fluorescence of CDs and a model is established to investigate the mechanism of fluorescence. In addition, white light-emitting diodes (WLEDs) are fabricated by utilizing the prepared CDs and rare earth luminescent materials (SrSi2O2N2:Eu and Sr2Si5N8:Eu) as color conversion layers and UV-LED chips as the excitation light source. The WLEDs produce bright white light with attractive color rendering properties including a color rendering index of up to 95.1, a CIE coordinate of (0.33, 0.37), and a T c of 5447 K under a 100 mA driven current, indicating that the CDs are promising in the field of optoelectronic devices.