  Visible light-driven production of fuels and value-added chemicals is
currently one of the most intensely investigated research topics across various
scientific disciplines, due to its potential to ease the World s dependence on
fossil fuels. In this perspective, we recapitulate some of the main features of
dye-sensitized photocatalytic systems aimed at solar H$_2$ production, focusing
in particular on TiO$_2$-based three-component assemblies with organic
sensitizers. Relevant aspects include the structural and electronic properties
of the sensitizers, the nature of the semiconductor and the hydrogen evolution
catalysts, the role of the sacrificial donor and the effect of the reaction
parameters on H$_2$ production rate and stability. Besides presenting the most
significant recent developments of the field, we also analyse some of its
common practices in terms of experimental design, laboratory procedures and
data presentation, trying to highlight their weaknesses and suggesting possible
improvements. We then conclude with a short paragraph discussing the possible
future development of this exciting research area.
