Efficient photocatalytic hydrogen evolution: Linkage units engineering in triazine-based conjugated porous polymers

Area of Science:

• Materials Science
• Photocatalysis
• Polymer Chemistry

Background:

• Conjugated porous polymers (CPPs) are explored as efficient photocatalysts.
• Optimizing molecular design and monomer selection is crucial for enhancing photocatalytic hydrogen production.

Purpose of the Study:

• To synthesize and investigate novel CPPs for photocatalytic hydrogen evolution.
• To evaluate the impact of peripheral group modifications on polymer performance.

Main Methods:

• Copolymerization of pyrene and 1,3,5-triazine building blocks.
• Synthesis of thiophene-linked (ThPy-CPP) and phenyl-linked (PhPy-CPP) CPPs.
• Assessment of photocatalytic hydrogen evolution rates under full-arc and visible light irradiation.

Main Results:

• Thiophene-linked CPPs exhibit wider visible light absorption, narrower band gaps, and improved charge carrier dynamics compared to phenyl-linked counterparts.
• ThPy-CPP achieved high hydrogen evolution rates (21.65 mmol g⁻¹h⁻¹ full-arc, 16.69 mmol g⁻¹h⁻¹ visible light) without noble metal co-catalysts.
• PhPy-CPP showed significantly lower rates (5.73 mmol g⁻¹h⁻¹ full-arc, 3.48 mmol g⁻¹h⁻¹ visible light).

Conclusions:

• Peripheral group modification in CPPs significantly influences photocatalytic activity.
• Thiophene-triazine based CPPs are highly efficient, cost-effective, noble metal-free photocatalysts for hydrogen evolution.
• This work offers a strategic direction for designing advanced CPPs for sustainable energy applications.