  We investigate the employment of carefully selected solvent additives in the
processing of a commercial perovskite precursor ink and analyze their impact on
the performance of organometal trihalide perovskite photovoltaic devices. We
provide evidence that the use of benzaldehyde can be used as an effective
method to preserve the stoichiometry of the perovskite precursors in solution.
Benzaldehyde based additive engineering shows to improve perovskite solid state
film morphology and device performance of trihalide perovskite based solar
cells.
