Bioengineered Protein Stabilized Perovskite Nanoplates in Polar Solvents.

Colloidally stabilized halide perovskite nanoparticles are promising for photocatalysis due to high absorption cross-section, high photoluminescence quantum yield, and nanoscale dimensions comparable to molecular reactants. Yet, their ionic lattice limits stability in polar media, complicating integration into aqueous catalytic systems. Here, we utilize stable protein 1 (SP1) as a bioinspired capping layer to protect perovskite nanoparticles from polar degradation while preserving their optoelectronic functionality, which stems from SP1's amphiphilic nature, featuring a hydrophilic exterior and a hydrophobic interior. Using bioengineered SP1 and its monomeric derivatives, we synthesize perovskite nanoplates with tunable quantum confinement that remain stable in an isopropanol polar environment. Protein screening reveals that stability in organic solvents, combined with suitable surface amine and carboxylate distributions, is crucial for nanoplate formation and stability, resulting in hybrids with superior spectroscopic stability in polar media. These findings provide design rules for protein-stabilized perovskites, paving the way for future solution-phase biocatalytic systems.