Researchers have developed a hollow CdS@polydopamine nanoreactor that mimics two key features of living cells, creating a highly organized platform for artificial photosynthesis and advanced chemical reactions at the nanoscale.
The study, published in the Journal of the American Chemical Society, was led by Prof. LI Can of the Dalian Institute of Chemical Physics (DICP) under the Chinese Academy of Sciences (CAS), in collaboration with Prof. Jian Liu’s team at Inner Mongolia University.
Engineering Cell-Inspired Chemistry at the Nanoscale
Living cells perform complex biochemical reactions with remarkable efficiency and precision. They achieve this control by organizing functional components within confined spaces, allowing molecules to diffuse, interact, and react under precisely regulated conditions.
Scientists are applying these biological principles to the design of advanced nanomaterials. This emerging field, known as nanocell engineering, focuses on creating cell-like structures with functional surfaces, internal pores, and nanoscale cavities. These synthetic systems, commonly called biomimetic nanoreactors, combine concepts from cell biology, nanotechnology, and catalysis.
Two Biomimetic Features Improve Nanoreactor Performance
The newly developed CdS@polydopamine nanoreactor incorporates two important cell-inspired features.
The first is a dynamic catechol/o-benzoquinone redox pair embedded in the polydopamine shell. Rather than functioning as an active proton pump, this redox pair acts as a proton relay. By repeatedly accepting and releasing protons, it accelerates proton-coupled electron transfer (PCET), a process that links proton and electron movement during photocatalytic reactions.
The second feature is the nanoreactor’s compartmentalized architecture. A hollow nanoscale cavity is enclosed by a porous polydopamine shell, creating a confined reaction environment that promotes reactant accumulation. The structure also facilitates molecular diffusion and enhances light trapping, improving the efficiency of sunlight-driven chemical reactions.
Efficient Hydrogen Peroxide Photosynthesis
These two features help balance the reaction rates of oxygen reduction and water oxidation, the two complementary half-reactions required for photocatalytic hydrogen peroxide production.
Under visible-light irradiation in an aqueous solution, the hollow CdS@polydopamine nanoreactor produced hydrogen peroxide at a rate of 3.24 mmol gcat.-1 h-1. The system also achieved a solar-to-chemical conversion efficiency of 1.2%, demonstrating its potential for artificial photosynthesis and solar fuel-related applications.
To investigate the reaction mechanism, the researchers used in situ spectroscopy, photochemical analysis, finite element simulations, and theoretical calculations. The combined results revealed how the cell-inspired design functions and clarified the Z-scheme heterojunction photocatalytic mechanism responsible for hydrogen peroxide synthesis.
Recyclable Photocatalysts for Solar-Driven Chemistry
The team also incorporated the nanoreactors into an environmentally friendly sodium alginate hydrogel matrix. This approach created solid and recyclable photocatalysts capable of continuously producing hydrogen peroxide under natural sunlight while maintaining stable catalytic performance.
“Our study provides a new strategy for engineering biomimetic nanoreactors that increasingly replicate the sophisticated functions of living cells, opening new opportunities in artificial photosynthesis, energy catalysis, and synthetic chemistry,” said Prof. Li.
Source: www.sciencedaily.com