Water Splitting–Biosynthetic Hybrid System for CO2 Conversion using Nickel Nanoparticles Embedded in N‐Doped Carbon Nanotubes

CO2 reduction has drawn increasing attention owing to the concern of global warming. Water splitting–biosynthetic hybrid systems are novel and efficient approaches for CO2 conversion. Intimate coupling of electrocatalysts and biosynthesis requires the catalysts possess both high catalytic performance and excellent biocompatibility, which is a bottleneck of developing such catalysts. Here, a complex of Ni nanoparticles embedded in N‐doped carbon nanotubes (Ni@N‐C) is synthesized as a hydrogen evolution reaction electrocatalyst and is coupled with a hydrogen oxidizing autotroph, Cupriavidus necator H16, to convert CO2 to poly‐β‐hydroxybutyrate. In Ni@N‐C, the Ni nanoparticles are encapsulated in N‐C nanotubes, which prevents bacteria from direct contact with Ni and inhibits Ni2+ leaching. As a result, Ni@N‐C exhibits excellent biocompatibility and stability. This work demonstrates that electrocatalysts and biosynthesis can be intimately coupled through rational catalyst design.