Researchers have long worked to address a grand challenge in synthesis science: to design and synthesize bio-inspired functional materials that rival those found in biology. If we can learn how to mimic in vivo functions of natural proteins—such as how biomolecules (e.g., proteins) and inorganic salts interact to form teeth, bones, or shell minerals—researchers might be able to apply the discovery to produce highly complex, designable, hybrid materials for energy-related applications.