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Polymeric semiconductors are finding a wide range of applications. In particular, graphitic carbon nitride g‐C3N4 has been investigated extensively in the past decade. However, the family of carbon nitrides is not limited to C3N4 and new CXNY are now being explored due to their different bandgap energy, morphology, and overall physicochemical properties. Here, homogenous and semi‐transparent C1N1 thin films are fabricated using guanine as a nontoxic molecular precursor. They are synthesized in a simplified chemical vapor deposition process on top of fused silica and fluorine doped tin oxide coated glass substrates. The chemical and structural studies reveal that C/N ratio is close to target 1, triazine vibrations are visible in vibrational spectra and stacking of the film is observed from glancing incidence X‐ray diffraction data. The (photo)electrochemical properties are studied, the film is a p‐type semiconductor with a good photoresponse to visible light and a suitable catalyst for hydrogen evolution reaction. A simple and safe way of synthesizing C1N1 films on a range of substrates is presented here. [ABSTRACT FROM AUTHOR]

Abstract: The efficient materials for Li-ion battery electrodes require suitable composition, high-crystallinity and appropriate structuration. The last one is important to assure an efficient exchange of Li ions between the anode and electrolyte, thus enhancing the kinetics of electrochemical reactions. Therefore, the synthesis of well-crystallized nano-sized electrode materials exhibiting high surface area is of great interest. Herein, we explore the influence of the glycothermal synthesis variations on the structure and porosity of Li4Ti5O12. The utilized precursors and their concentration have a minor influence on crystallites size, but they could be used to control the porosity of assembled particles. The prepared Li-ion battery anode could be charged at low and high rate reaching the theoretical capacity of Li4Ti5O12. The material retains its peculiar porous structuration even after 1000 cycles at charging/discharging rate of 50C which contributes to the lack of capacity fading. Additionally, 7Li NMR is performed on one of synthesized nano-structured Li4Ti5O12 and compared with commercially available nanosized Li4Ti5O12 to understand the excellent electrochemical performance.Glycothermal synthesis of lithium titanate, in 1,4-butanediol leads to crystalline NPs of 4-5 nm assembled into highly porous microstructures. Such structuration assures well-developed contact area between the electrode and an electrolyte in Li-ion batteries, which facilitates exchange of Li-ions. Therefore, the material shows excellent electrochemical performances. LTO characterized by different nanostructuration is obtained by varying the synthesis conditions (precursors type and concentration, temperature and co-solvent). Pure nanostructure Li4Ti5O12 was synthesized in varying glycothermal conditions using 1,4-butanediol as the solvent.Simple adjustment of precursors and their concentration tuned the microstructure of the material without affecting the size of crystallites which oscillated around 4 nm.Nano-scaling and proper microstructuration is an effective way to improve kinetics of electrochemical reactions due to the efficient exchange of Li ions between electrodes and electrolytes.7Li NMR was performed on synthesized material and commercial one in order to understand the peculiar electrochemical properties of the material. [ABSTRACT FROM AUTHOR]

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Understanding how water interacts with nanopores of carbonaceous electrodes is crucial for energy storage and conversion applications. A high surface area of carbonaceous materials does not necessarily need to translate to a high electrolyte-solid interface area. Herein, we study the interaction of water with nanoporous C1N1 materials to explain their very low specific capacity in aqueous electrolytes despite their high surface area. Water was used to probe chemical environments, provided by pores of different sizes, in 1H MAS NMR experiments. We observe that regardless of their high hydrophilicity, only a negligible portion of water can enter the nanopores of C1N1, in contrast to a reference pure carbon material with a similar pore structure. The common paradigm that water easily enters hydrophilic pores does not apply to C1N1 nanopores below a few nanometers. Calorimetric and sorption experiments demonstrated strong water adsorption on the C1N1 surface, which restricts water mobility across the interface and impedes its penetration into the nanopores., (© 2024 Wiley‐VCH GmbH.)

The oligomers of carbon suboxide, known as red carbon, exhibit a highly conjugated structure and semiconducting properties. Upon mild heat treatment, it transforms into a carbonaceous framework rich in oxygen surface terminations, called oxocarbon. In this study, the abundant oxygen functionalities are harnessed as anchors to create oxocarbon-supported nanohybrid electrocatalysts. Starting with single atomic Cu (II) strongly coordinated to oxygen atoms on red carbon, the Fehling reaction leads to the formation of Cu 2 O clusters. Simultaneously, a covalent oxocarbon framework emerges via cross-linking, providing robust support for Cu 2 O clusters. Notably, the oxocarbon support effectively stabilizes Cu 2 O clusters of very small size, ensuring their high durability in acidic conditions and the presence of ammonia. The synthesized material exhibits a superior electrocatalytic activity for nitrate reduction under acidic electrolyte conditions, with a high yield rate of ammonium (NH 4 + ) at 3.31 mmol h -1  mg cat -1 and a Faradaic efficiency of 92.5% at a potential of -0.4 V (vs RHE)., (© 2024 Wiley‐VCH GmbH.)

The design of high-performance energy-converting materials is an essential step for the development of sensors, but the production of the bulk materials currently used remains costly and difficult. Therefore, a different approach based on the self-assembly of nanoparticles has been explored. We report on the preparation by solvothermal synthesis of highly crystalline CeF 3 nanodiscs. Their surface modification by bisphosphonate ligands led to stable, highly concentrated, colloidal suspensions in water. Despite the low aspect ratio of the nanodiscs (∼6), a liquid-crystalline nematic phase spontaneously appeared in these colloidal suspensions. Thanks to the paramagnetic character of the nanodiscs, the nematic phase was easily aligned by a weak (0.5 T) magnetic field, which provides a simple and convenient way of orienting all of the nanodiscs in suspension in the same direction. Moreover, the more dilute, isotropic, suspensions displayed strong (electric and magnetic) field-induced orientation of the nanodiscs (Kerr and Cotton-Mouton effects), with fast enough response times to make them suitable for use in electro-optic devices. Furthermore, an emission study showed a direct relation between the luminescence intensity and magnetic-field-induced orientation of the colloids. Finally, with their fast radiative recombination decay rates, the nanodiscs show luminescence properties that compare quite favorably with those of bulk CeF 3 . Therefore, these CeF 3 nanodiscs are very promising building blocks for the development and processing of photosensitive materials for sensor applications.