Modern civilization highly depends on energy and the sun is the most abundant clean and available energy on Earth. Being able to exploit it efficiently would result in a great environmental and economic breakthrough. Among the photovoltaic devices, dye-sensitized solar cells (DSCs) emerged for their tremendous commercial potential deriving from a combination of low-cost production and attractive features, such as flexibility and transparency, for indoor and outdoor applications. In the DSCs, a dye anchored to a semiconductor layer (typically TiO2) is responsible for capturing the sunlight and converting it into electricity. Nevertheless, existing commercialized dyes for DSCs are based on a very rare metal, ruthenium, and its replacement with a cheap, abundant metal is desirable for spreading this technology.