Chrome plating is still one of the best solutions to coat martensitic steel used in the molding of plastics and rubbers. However, current stringent regulations on environmental impact call for more sustainable processes. In the present work, some physical vapor deposition (PVD) nitride coatings were produced on X155CrMoV12 steel and characterized in terms of both corrosion behavior and surface properties. Results indicated that titanium-based PVD coatings could be a valuable alternative to chromium-based coatings as they exhibited a good compromise between corrosion and surface properties. AlTiN and TiN PVD coatings exhibited adequate hardness for plastic mold applications, with AlTiN reaching hardness as high as 2000 HV. Moreover, the critical loads and adhesion properties were found to be definitely better than those of chromium-based coatings. From a corrosion point of view, the presence of multilayers in AlTiN did not seem to be beneficial as the breakdown potential for TiN (single layer) was ca. 1.1 V vs. saturated calomel electrode (SCE) compared to 0.85 V vs. SCE for AlTiN in aggressive media (NaCl).

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Mixed CO/NO-releasing molecules were prepared by conjugation of the 17-electron rhenium dicarbonyl cis-[Re(CO)2Br4](2-) complex to N-nitrosamine modified cyanocobalamin (B12) bio-vectors. The species were fully characterized by standard analytical techniques, including X-ray crystallography for cyanocobalamin-5'-O-pyrazine and () and its N-pyrazine nitrosylated derivative (). The N-nitrosamine B12 derivatives are able to liberate low NO doses in buffer solutions and appear to be "activated" towards NO release if in contact with cultured cells. Coordination of the cis-[Re(CO)2Br4](2-) complex on the axial cyanide of B12 allows for the combined loss of CO and NO from the conjugates. The mixed CO/NO-releasing molecules show cytoprotection in an ischemia-reperfusion model but no significant enhanced synergistic effects over the relative NORMs and CORMs building constituents.

A comparative evaluation of traditional and innovative coatings for outdoor bronze surfaces was carried out, including blending or pre-treatment with non-toxic corrosion inhibitors on bare and patinated bronze surfaces to simulate both as cast and aged surfaces. Coatings recently applied in bronze conservation practice, commercially available coatings and an innovative endcapped poly(lactic acid) with a benzotriazole (BTA) moiety have been tested, as well as a triple-layer system (wax/acrylic polymer/ wax). BTA, single-layer Soter wax, and double layer Incral44/Soter wax were used as a reference. The products were evaluated in terms of aesthetic features, molecular structure, and corrosion protection by means of colorimetric, spectroscopic, and electrochemical tests. All inhibitors showed similar or significantly better results compared to BTA. In particular, sodium oleate and tolyltriazole could be considered as promising lower-toxicity alternatives to BTA, while the triple-layer coating applied without pre-filming inhibitors proved to give a very high protection against corrosion.