Light-Driven Self-Cascade Peroxidase-like Nanozymes without Exogenous H₂O₂

Area of Science:

• Materials Science
• Nanotechnology
• Catalysis

Background:

• Peroxidase (POD)-like nanozymes traditionally require external hydrogen peroxide (H2O2) for activity.
• Previous strategies to overcome this limitation involved cascade reactions for H2O2 production.
• A need exists for self-sufficient nanozyme systems that generate substrates in situ.

Purpose of the Study:

• To develop a light-driven self-cascade strategy for constructing POD-like nanozymes.
• To synthesize a novel nanozyme capable of in situ H2O2 generation and substrate oxidation.
• To explore the application of this nanozyme in a photofuel cell.

Main Methods:

• Synthesis of a model nanozyme, resorcinol-formaldehyde resin-Fe3+ (RF-Fe3+), utilizing a hydroxyl-rich photocatalytic material (RF) as a carrier.
• In situ chelation of metal oxides within the RF matrix for simultaneous H2O2 generation and POD-like activity.
• Construction and performance evaluation of a dual photoelectrode-assisted photofuel cell using the RF-Fe3+ photocathode.

Main Results:

• The synthesized RF-Fe3+ nanozyme effectively generates H2O2 under irradiation and exhibits POD-like catalytic behavior.
• The RF carrier provides high affinity to H2O2 due to its adsorption capabilities and hydroxyl-rich nature.
• A photofuel cell constructed with RF-Fe3+ achieved a high power density of 120 ± 5 μW cm-2.

Conclusions:

• A novel self-cascade strategy for in situ substrate generation in nanozymes has been successfully demonstrated.
• The RF-Fe3+ nanozyme offers a promising platform for light-driven catalysis without exogenous H2O2.
• This work opens new avenues for extending the application of nanozymes in catalytic fields, including energy conversion.