Mesoporous TiN microspheres with hierarchical chambers and enhanced visible light-driven hydrogen evolution

Area of Science:

• Materials Science
• Nanotechnology
• Photocatalysis

Background:

• Titanium nitride (TiN) is a promising material for photocatalysis.
• Developing efficient photocatalysts for visible light water splitting remains a challenge.
• Controlling the morphology and structure of TiN is crucial for optimizing its performance.

Purpose of the Study:

• To synthesize mesoporous titanium nitride (TiN) microspheres with tunable chamber structures.
• To investigate the photocatalytic activity of different TiN morphologies for water splitting.
• To understand the structure-property relationships governing the enhanced performance of yolk-shell TiN.

Main Methods:

• Organotitania precursors were synthesized via solvothermal alcoholysis.
• Ammonia (NH3) nitridation was employed to convert organotitania into TiN microspheres.
• The resulting TiN structures (solid, yolk-shell, hollow) were characterized.
• Visible light-induced photocatalytic water splitting experiments were conducted to measure H2 evolution efficiency.

Main Results:

• Mesoporous TiN microspheres with tunable solid, yolk-shell, and hollow chamber structures were successfully synthesized.
• Yolk-shell TiN exhibited significantly higher H2 evolution efficiency compared to solid, hollow, and crushed TiN.
• The enhanced performance was attributed to a narrow energy band gap, high surface area, and excellent electrical conductivity.
• The yolk-shell TiN demonstrated efficient photoelectron-hole separation and suppressed recombination.

Conclusions:

• Tunable mesoporous TiN microspheres, particularly the yolk-shell structure, are highly effective for visible light photocatalytic water splitting.
• The unique yolk-shell architecture facilitates light absorption, reactant adsorption, and charge separation.
• This TiN material offers a promising, recyclable, and noble metal-free alternative for sustainable hydrogen production.