Nickel Single Atoms Reconfigured 3D COFs Boost H₂O₂ Photosynthesis

Area of Science:

• Materials Science
• Chemistry
• Nanotechnology

Background:

• Traditional 2D covalent organic frameworks (2D COFs) face challenges like limited active sites and inefficient charge transport.
• Novel 3D COFs offer potential for improved structures and functions, addressing limitations of 2D counterparts.

Purpose of the Study:

• To design and synthesize a 3D COF with a unique helical-staggered topology for photocatalytic applications.
• To enhance photocatalytic hydrogen peroxide (H2O2) production by integrating nickel centers into the 3D COF structure.

Main Methods:

• Sequential covalent assembly and nickel anchoring to create a 3D COF (PhFOONi-COF).
• Utilizing in situ investigations and density functional theory (DFT) calculations to understand the mechanism.
• Photocatalytic testing for H2O2 production under visible light.

Main Results:

• The synthesized 3D COF exhibits a helical-staggered interlayer-connected topology.
• Achieved a H2O2 production rate of 9.73 mmol g⁻¹ h⁻¹, 15 times higher than its 2D counterpart.
• Demonstrated dual functionality: Ni-N4 sites for O2 confinement and conjugated fluorenone skeleton for electron funneling.

Conclusions:

• The integrated covalent-coordination network in 3D COFs offers a paradigm-shifting strategy for multifunctional photocatalysis.
• This approach effectively balances activity and selectivity in photocatalytic H2O2 production.
• Pioneered atomic-level integration of covalent and coordination networks for advanced photocatalytic platforms.