A TiO₂/C catalyst having biomimetic channels and extremely low Pt loading for formaldehyde oxidation

Formaldehyde oxidation is a critical process in air purification systems. Prior research has shown that platinum-based catalysts are effective for this task. However, high Pt loading increases costs and reduces scalability. No prior work had resolved how to maintain high reactivity with minimal Pt. The use of carbon-based frameworks has been explored, but integration with hierarchical porosity remains limited. Wood-derived templates have not been widely applied in catalyst synthesis. This gap motivated the search for alternative methods. The need for cost-effective and scalable catalysts remains unmet. This paper introduces a novel approach using wood as a structural and reducing agent.

The study aimed to develop a low-cost, high-efficiency catalyst for formaldehyde oxidation. The specific problem addressed was the high Pt loading required in conventional catalysts. The motivation was to create a catalyst that maintains activity at room temperature. The goal was to use a wood template to fabricate a TiO₂/C hybrid material. The researchers sought to eliminate the need for post-reduction treatments. They aimed to control pore structures through calcination conditions. The method was designed to be scalable for industrial applications. This approach could reduce reliance on expensive catalysts.

The method involved using pretreated wood chips as a template. The wood was repeatedly impregnated with a titanium precursor solution. Calcination was performed at 400–600 °C for four hours under nitrogen. The process produced TiO₂ nanocrystals embedded in a carbon matrix. The calcination atmosphere influenced pore structure formation. SEM and BET analyses confirmed hierarchical porosity. The catalyst contained Pt at 0.04–0.1 wt%. The wood template also acted as a Pt reduction agent.

The TiO₂/C catalyst achieved nearly complete formaldehyde conversion at room temperature. The catalyst required only 0.04–0.1 wt% Pt loading. The material exhibited mesopores (2–10 nm) and larger channels (20 μm). SEM and BET data confirmed the hierarchical structure. The catalyst did not require post-reduction treatments. The wood template served as both a structural and chemical agent. The calcination temperature controlled pore size distribution. The catalyst demonstrated high stability and reactivity.

The authors propose that the wood-derived template enabled low Pt loading and high reactivity. The hierarchical porosity improved formaldehyde oxidation efficiency. The elimination of post-reduction steps reduced costs. The calcination atmosphere influenced pore structure formation. The method's scalability was supported by wood's abundance. The catalyst's performance at room temperature was notable. The study suggests that this approach could be applied in air purification systems. The findings support the potential for industrial adoption.