How to approach a Grätzel solar cell in a multivariate way

Nowadays, modern science proposes and optimizes new materials and technologies, whose characteristics and performances are governed by many factors. However, the scientific community rarely adopts multivariate strategies for the comprehension of what is proposed. As a striking example, a standard dye-sensitized solar cell (DSSC) is a typical complex system assembled with different and heterogeneous layers (FTO/nanocrystalline semiconductor/sensitizer/electrolyte/Pt-FTO), each one affected by intrinsic variability; moreover the layers influence each other and this increases the number of variables involved at the same time in the photoconversion process. Thousands of articles have been published to study a single parameter or component of DSSCs, but a comprehensive approach which considers all the experimental factors simultaneously has never adopted. In this work, we show how chemometric design of experiments (DoE) can be used for the formulation of UV-cured polymer electrolyte membranes, for the preparation of a cellulose-based gel-polymer electrolyte, for the proper sensitization of a ZnO photoanode and for the photostability optimization of a series of NIR dyes under different dipping conditions.