Unraveling the Link between Catalytic Activity and Agglomeration State with Scanning Electrochemical Microscopy and Atomic Force Microscopy.

In this article, we set up a methodology to investigate the relationship between the catalytic activity and the agglomeration state of platinum group metal-free ORR catalysts. To this end, we have developed a statistical approach based on scanning electrochemical microscopy (SECM) and atomic force microscopy (AFM). Two catalysts are investigated at very low loadings in order to access their intrinsic activity.

Local probe investigation of electrocatalytic activity.

As the world energy crisis remains a long-term challenge, development and access to renewable energy sources are crucial for a sustainable modern society. Electrochemical energy conversion devices are a promising option for green energy supply, although the challenge associated with electrocatalysis have caused increasing complexity in the materials and systems, demanding further research and insights. In this field, scanning probe microscopy (SPM) represents a specific source of knowledge and understanding.

Bifunctional coatings: coupling an organic adhesion promoter with an anticorrosion inorganic layer.

In this work, a multifunctional non-toxic chromium free treatment is proposed. Hexavalent chromium, largely used for anticorrosion surface treatments of aluminum alloys in aeronautics, will soon be completely banned due to its high toxicity (European REACH regulation) and new solutions are required. Here, in a first step, a polymeric film was grafted at the aluminum surface by the surface induced reduction of a diazonium salt.

Ideal optical contrast for 2D material observation using bi-layer antireflection absorbing substrates.

The capability to observe 2D materials with optical microscopy techniques is of central importance in the development of the field and is a driving force for the assembly and study of 2D material van der Waals heterostructures. Such an observation of ultrathin materials usually benefits from antireflection conditions associated with the choice of a particular substrate geometry. The most common configuration uses a transparent oxide layer with a thickness minimizing light reflection at the air/substrate interface when light travels from air to the substrate.

Electronic Transport of MoS Monolayered Flakes Investigated by Scanning Electrochemical Microscopy.

The amazing properties of 2D materials are envisioned to revolutionize several domains such as flexible electronics, electrocatalysis, or biosensing. Herein we introduce scanning electrochemical microscopy (SECM) as a tool to investigate molybdenum disulfide in a straightforward fashion, providing localized information regarding the electronic transport within chemical vapor deposition (CVD)-grown crystalline MoS single layers having micrometric sizes. Our investigations show that within flakes assemblies some flakes are well electrically interconnected, with no detectable contact resistance, whereas others are not electrically connected at all, independent of the size of the physical contact between them.