Am ajor handicap towards the exploitation of radicals is their inherent instability.I nt he paramagnetic azafullerenyl radical C 59 NC,t he unpaired electron is strongly localized next to the nitrogen atom, which induces dimerization to diamagnetic bis(azafullerene), (C 59 N) 2 .C onventional stabilization by introducing steric hindrance around the radical is inapplicable here because of the concave fullerene geometry. Instead, we developed an innovative radical shielding approach based on supramolecular complexation, exploiting the protection offered by a[ 10]cycloparaphenylene ([10]CPP) nanobelt encircling the C 59 NC radical. Photoinduced radical generation is increased by af actor of 300. The EPR signal showing characteristic 14 Nh yperfine splitting of C 59 NC& [10]CPP was traced even after several weeks,w hichc orresponds to alifetime increase of > 10 8 .The proposed approach can be generalized by tuning the diameter of the employed nanobelts,opening new avenues for the design and exploitation of radical fullerenes.

Conversely,d eveloped strategies for the edge and in-plane covalent functionalization of MoS 2 mainly concern chemistry at Sv acancies, direct CÀSb ond formation, and coordination of Se dges at metal centers. Herein, we focus into the most representative molecular doping strategies and material designing of MoS 2 -based hybridn anostructuresc arrying photo-and/ore lectro-active components.K ey points related with the exfoliation routes, the surface functionalization approachesa nd their impact on the electronic properties of the functionalized nanosheets are comprehensively discussed, offering at oolbox for scientists of different disciplines interested in putting as tep forwardi nt he field of transition-metal dichalcogenide-based materials.The ORCID identification number(s) for the author(s) of this articlecan be found under: https://doi.

Molybdenum disulfide nanosheets covalently modified with porphyrin were prepared and fully characterized. Neither the porphyrin absorption nor its fluorescence was notably affected by covalent linkage to MoS2. The use of transient absorption spectroscopy showed that a complex ping‐pong energy‐transfer mechanism, namely from the porphyrin to MoS2 and back to the porphyrin, operated. This study reveals the potential of transition‐metal dichalcogenides in photosensitization processes.

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SummaryGraphene research and in particular the topic of chemical functionalization of graphene has exploded in the last decade. The main aim is to increase the solubility and thereby enhance the processability of the material, which is otherwise insoluble and inapplicable for technological applications when stacked in the form of graphite. To this end, initially, graphite was oxidized under harsh conditions to yield exfoliated graphene oxide sheets that are soluble in aqueous media and amenable to chemical modifications due to the presence of carboxylic acid groups at the edges of the lattice. However, it was obvious that the high-defect framework of graphene oxide cannot be readily utilized in applications that are governed by charge-transfer processes, for example, in solar cells. Alternatively, exfoliated graphene has been applied toward the realization of some donor–acceptor hybrid materials with photo- and/or electro-active components. The main body of research regarding obtaining donor–acceptor hybrid materials based on graphene to facilitate charge-transfer phenomena, which is reviewed here, concerns the incorporation of porphyrins and phthalocyanines onto graphene sheets. Through illustrative schemes, the preparation and most importantly the photophysical properties of such graphene-based ensembles will be described. Important parameters, such as the generation of the charge-separated state upon photoexcitation of the organic electron donor, the lifetimes of the charge-separation and charge-recombination as well as the incident-photon-to-current efficiency value for some donor–acceptor graphene-based hybrids, will be discussed.

The game-changing role of graphene oxide (GO) in tuning the excitonic behavior of conjugated polymer nanoparticles is described for the first time. This is demonstrated by using poly(3-hexylthiophene) (P3HT) as a benchmark conjugated polymer and employing an in situ reprecipitation approach resulting in P3HT nanoparticles (P3HT NPs ) with sizes of 50-100 nm in intimate contact with GO. During the self-assembly process, GO changes the crystalline packing of P3HT chains in the forming P3HT NPs from H to H/J aggregates exhibiting exciton coupling constants as low as 2 meV, indicating favorable charge separation along the P3HT chains. Concomitantly, π-π interface interactions between the P3HT NPs and GO sheets are established resulting in the creation of P3HT NPs -GO charge-transfer complexes whose energy bandgaps are lowered by up to 0.5 eV. Moreover, their optoelectronic properties, preestablished in the liquid phase, are retained when processed into thin films from the stable aqueous dispersions, thus eliminating the critical dependency on external processing parameters. These results can be transferred to other types of conjugated polymers. Combined with the possibility of employing water based "green" processing technologies, chargetransfer complexes of conjugated polymer nanoparticles and GO open new pathways for the fabrication of improved optoelectronic thin film devices.

Mixed halide hybrid perovskites are strong candidates for fabrication of efficient, stable and reproducible perovskite solar cells (PSCs). To restrain intrinsic volatility and ionic migration effects, we report for the first time a dimensionality engineering approach consisting of a (FA/MA/Cs)PbI 3−x Br x /(CH 3 ) 3 SPbI 3 (3D/1D) perovskite bilayer architecture, fabricated exclusively with solution processes. XRPD analysis showed no degradation of the 3D/1D composite structure after more than one month of exposure in ambient conditions, in contrast to the reference 3D samples (sole (FA/MA/Cs)PbI 3−x Br x ) which gradually decomposed to PbI 2 . The 3D/1D bilayer structure further optimizes the corresponding absorber/hole transporting layer (HTL) interface of the PSCs, since the (FA/MA/Cs)PbI 3−x Br x perovskite layer acts as the primary absorber and the (CH 3 ) 3 SPbI 3 top layer plays the role of a barrier against ionic migration/charge carrier recombination. The latter leads to a significant stability improvement for nonsealed devices both under ambient conditions and light stress, underscoring the potential of interface engineering for developing highly efficient and stable PSCs based on functional 3D/1D perovskite bilayers.

Stable and abundant spin-1/2 species from azafullerene (C59N˙) supramolecularly hosted in [10]cycloparaphenylene nanohoops are operated as stable qubits, with possibility of qubit wiring via intermediate polymerized spin-redistributed states.