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Photocatalytic generation of H2 via water splitting emerges as a promising avenue for the next generation of green hydrogen due to its low carbon footprint. Herein, a versatile platform is designed to the preparation of functional π‐conjugated organic nanoparticles dispersed in aqueous phase via mini‐emulsification. Such particles are composed of donor–acceptor–donor (DAD) trimers prepared via Stille coupling, stabilized by amphiphilic block copolymers synthesized by reversible addition‐fragmentation chain transfer polymerization. The hydrophilic segment of the block copolymers will not only provide colloidal stability, but also allow for precise control over the surface functionalization. Photocatalytic tests of the resulting particles for H2 production resulted in promising photocatalytic activity (≈0.6 mmol g−1 h−1). This activity is much enhanced compared to that of DAD trimers dispersed in the water phase without stabilization by the block copolymers. [ABSTRACT FROM AUTHOR]

A biopolymer derived from Kraft Black Liquor (KBL), a byproduct of the paper industry composed mainly of lignin and hemicellulose, has been successfully filled with three different types of carbon black (CB) that differ in their specific surface areas, sizes, shapes and surface heteroatoms. These composite CB–KBL dispersions have been subsequently employed to generate porous monoliths through an emulsion-polymerization templating process. After carbonization, the fillers' influence over the resulting carbon monolith structures and textures is investigated. In particular, beyond XRD, Raman spectroscopy demonstrates improved sample structuration through CB filler addition while nitrogen sorption measurements reveal the influence of the fillers over the final composite's porosities. Considering their properties and effectiveness, hydrogen storage at 77 K reveals that some materials offer up to 1.4 wt% of H2 storage capacity, being higher than that of some commercial carbon materials (with the same specific surface) offering 1.2 wt% hydrogen retention. When addressing their electrochemical energy storage properties, some of these electrode materials deliver extremely promising specific capacities and rate capabilities, with values up to 47 mA h g−1 at 1 A g−1 in alkaline electrolyte, higher than those of the well-known "YP-80F" commercial material tested under the same conditions. These enhanced energy storage properties, while employing a high tonnage paper industry by-product as a carbonaceous source and carbon blacks as structural and textural modifiers, render these materials realistic candidates favoring a sustainable energy transition. [ABSTRACT FROM AUTHOR]

Given the increase in current density in the constituent materials of electrical systems, improving the electrical conductivity of these materials, particularly copper (Cu), is crucial. This would also help to mitigate the heat generated by Joule heating. The incorporation of graphene (Gr) into a composite material (Cu/Gr) is a viable solution. However, to ensure the proper transfer of properties between the reinforcement and the matrix, several elements must be considered, including the orientation of the reinforcement. As a 2D material, controlling graphene's orientation within the structure is essential but often overlooked. To address this issue, hot rolling was implemented to improve the alignment of the reinforcement. The inclusion of graphene led to a 12 HV increase in the material's hardness, demonstrating a positive composite effect. Simultaneously, rolling increased the material's hardness from 67.6 to 75.1 HV by introducing more dislocations into the material. To characterize the graphene's alignment, polarized Raman spectroscopy was used. This technique highlighted the improved alignment of the reinforcement in the rolling direction, a change that was visible and confirmed by scanning electron microscopy micrographs. [ABSTRACT FROM AUTHOR]

In the present work, the effects of (i) Ti replacement by Hf and (ii) the synthesis method on microstructure and crystal structure evolution in the high-entropy alloy HfxTi(1−x)NbVZr are reported. The results of scanning electron microscopy and X-ray diffraction analysis of alloys prepared by both arc-melting and induction-melting are compared with theoretical thermodynamic calculations using the CALPHAD approach. The non-equilibrium thermodynamic calculations agree well with the experimental observations for the arc-melted alloys: a mixture of body-centered cubic (BCC) and cubic C15 Laves phases occurs for low-Ti-concentration alloys and a single BCC phase is obtained for high-Ti alloys. The agreement is not as good when using the induction-melting method: equilibrium solidification calculations predict that the most stable state is a phase mixture of BCC, hexagonal close-packed, and a cubic C15 Laves phase, while experimentally only one BCC and one hexagonal C14 Laves phase were found. The estimation of the exact cooling rate and the lack of a thermodynamic database can explain the difference. In addition, for both methods, the thermodynamic calculation confirms that for a high Ti concentration, the BCC phase is stable, whereas phase separation is enhanced with a higher Hf concentration. [ABSTRACT FROM AUTHOR]

Front Cover: A versatile platform is developed for creating functional π‐conjugated organic nanoparticles stabilized by amphiphilic block copolymers for green H2 photocatalytic generation. The donor–acceptor–donor trimers nanoparticles show enhanced photocatalytic activity (≈0.6 mmol g−1 h−1) for H2 production via water splitting. More details can be found in article 2400395 by Thiago R. Guimarães, Jean‐Louis Bobet, Eric Cloutet, and co‐workers..By Thiago R. Guimarães; Alisha Khan; Hynd Remita; Jean‐Louis Bobet and Eric CloutetReported by Author; Author; Author; Author; Author [Extracted from the article]