ZnS is a versatile wide-gap semiconductor that shows remarkable chemical stability against oxidation and hydrolysis. These properties are retained when the particle size steps down to 10 nm and below, and thus ZnS nanoparticles are interesting entities for optical and catalytic functions, where they might be exposed to quite aggressive environments. Moreover, ZnS may be doped by a host of elements, so that the electrical and optical properties can be tuned over an extended range. Neither Zn nor S are in short supply, and ZnS as compound or in view of the constituting elements is not toxic. Therefore, functional materials based on ZnS will be ideal for "green chemistry" applications, since they are suited also for large scale manufacture and will pose no additional problems when released into the environment. The article describes first results for ZnS-nanoparticles acting as electrocatalysts, a field that has not been covered so far by ZnS-derived materials. The catalytic action is evaluated for the decomposition of ethanol, a potentially abundant fuel for mobile electricity generation, since it can be fabricated by fermentation from a broad range of organic materials.