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Transition metal dichalcogenides (TMDs) have garnered attention as potential catalysts for water splitting owing to their unique structures, diverse electronic properties, and composition from earth‐abundant elements. While certain TMD catalysts, notably MoS2, have shown promising activity for hydrogen evolution reactions (HER), achieving performance comparable to traditional platinum catalysts remains a challenge. While significant effort has been invested into understanding the effect of TMD's structural properties, such as defectiveness and crystalline phases, recent work has emphasized the role of extrinsic factors on HER. This review summarizes the current understanding of the impact of commonly overlooked electrocatalytic effects that exhibit an enhanced importance in TMD‐based HER. By combining recent advances in theoretical modeling and experimental work, we review the dominating effects of extrinsic factors including electronic resistance, interfacial barriers, surface roughness, oxidation, and valence impurities. Our work aims to provide insights into optimizing TMDs as highly efficient catalysts for HER, facilitating future advancements in hydrogen generation technology. [ABSTRACT FROM AUTHOR]

We demonstrate the strengthening of graphene, an atomically thin carbon allotrope, by out-of-plane folding. Through lateral confinement of graphene at the water–air interface, nanoscale buckling was induced in suspended flakes, leading to an unexpected folding transition beyond a critical surface pressure. The emergence of folding was confirmed by in situ Brewster angle reflectivity and ex situ microscopy, showing a unique "z-laminated" nanostructure. Molecular dynamics simulations indicate that z-lamination yields an enhanced adhesion between neighboring flakes compared to lateral sliding, which was confirmed by a surface pressure hysteresis during the folding process. Mechanical testing reveals superior Young's modulus and yield strength when compared to conventional graphene assemblies and even compared to composites. We demonstrate the potential of the z-lamination approach for applications in graphene-based structural materials, tribological layers, and functional electrochemical coatings. Finally, the complete recyclability of z-laminated graphene opens up new routes toward sustainable nanostructured materials. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials promise advances in electronic devices beyond Moore's scaling law through extended functionality, such as non-monotonic dependence of device parameters on input parameters. However, the robustness and performance of effects like negative differential resistance (NDR) and anti-ambipolar behavior have been limited in scale and robustness by relying on atomic defects and complex heterojunctions. In this paper, we introduce a novel device concept that utilizes the quantum capacitance of junctions between 2D materials and molecular layers. We realized a variable capacitance 2D molecular junction (vc2Dmj) diode through the scalable integration of graphene and single layers of stearic acid. The vc2Dmj exhibits NDR with a substantial peak-to-valley ratio even at room temperature and an active negative resistance region. The origin of this unique behavior was identified through thermoelectric measurements and ab initio calculations to be a hybridization effect between graphene and the molecular layer. The enhancement of device parameters through morphology optimization highlights the potential of our approach toward new functionalities that advance the landscape of future electronics. [ABSTRACT FROM AUTHOR]

Local laser‐induced oxidation is an extremely valuable technique to perform high‐throughput optimization across multidimensional parameter sets. In this work, a versatile method is presented for the synthesis of titanium dioxide (TiO2) thin‐films with varying crystalline structures through the use of localized, visible, continuous‐wave laser‐processing. By controlling the laser intensity and the exposure time, the conversion of amorphous titanium disulfide (a‐TiS2) precursor films into distinct phases of TiO2 is achieved and a laser‐induced oxidation phase diagram is constructed with the resulting material phases, including anatase, rutile, and black TiO2. By utilizing the dependence of phase formation on the rate and duration of laser energy input, mixtures of anatase and rutile phases are fabricated with controlled spatial arrangements. Photocatalytic properties of the synthesized films are evaluated using the degradation of nitrogen oxide (NOx) gas under UV illumination and an organic dye under white‐light illumination, revealing that mixtures of anatase and rutile phases demonstrate superior photocatalytic activity. The laser‐induced oxidation method highlighted showcases a strategy for precisely tailored phase composition for directly tunable properties, paving the way for in‐depth studies into structure‐property relationships in photocatalysis and other applications of metal oxide films. [ABSTRACT FROM AUTHOR]

Future energy generation and storage requirements emphasize the importance of high-performance electrocatalysis. MoS2 edges exhibit ideal energetics for hydrogen evolution reactions (HERs) if challenges in their kinetics are addressed. Herein, we investigate the emergence of edge-dominated electrochemical reaction kinetics in ultra-narrow MoS2 nanoribbons. A templated subtractive patterning process (TSPP) served as a powerful platform that yields large arrays of MoS2 nanoribbons. Nanoribbons with widths below 30 nm exhibit significantly increased reaction kinetics, as evidenced by a ∼200-fold enhanced turn-over frequency, an 18-fold increased exchange current density, and a 38% decreased Tafel slope. These improvements are due to increased charge transfer efficiency from the basal plane toward the edge sites. Photo-electrocatalytic measurements and carrier transport simulations reveal the impact of suppressed band bending in nanoribbons below the depletion width toward achieving edge-dominated HER. Our results demonstrate the potential of confinement in electrocatalysis and provide a universal route toward nanoribbon-enhanced electrochemistry. [ABSTRACT FROM AUTHOR]