Screening the photoelectrochemical activity of dyes on TiO2 surfaces is becomingincreasingly relevant as industry tries to expand commercialisation of dye-sensitized solar cells (DSSCs).

Scanning electrochemical microscopy (SECM) offers a unique means with which to map the chemical and electrochemical activity of surfaces in the liquid phase. Here we demonstrate how SECM, together with photoexcitation of dispensed arrays of dye spots can be used as a powerful yet low-cost dye screening method.