Mesoporous Silica with Site‐Isolated Amine and Phosphotungstic Acid Groups: A Solid Catalyst with Tunable Antagonistic Functions for One‐Pot Tandem Reactions

Cooperative Surface‐Particle Catalysis: The Role of the “Active Doughnut” in Catalytic Oxidation

“…This can complicate things compared to the classic Langmuir‐Hinshelwood model, where the steps of diffusion and adsorption/desorption are often discounted, especially in cases where the chemical reaction at the active site is rate‐determining. If a tandem system comprises two separate cycles (for example an acid‐catalysed reaction at one site followed by a base‐catalysed reaction at another), then the classical model suffices. But when a catalytic cycle requires both sites, the diffusion of short‐lived intermediates between these sites cannot be ignored …”

Decoration of chitosan microspheres with Brønsted heteropolyacids and Lewis ion Ti: trifunctional catalysts for esterification to biodiesel

“…4,5 Articial HPA materials functionalized by acid-base synergy and cooperative effects are relatively less addressed and stimulate a real challenge. The rst report on bifunctional HPAs catalysis with acidic and basic sites was reported by N. R. Shiju and co-workers, demonstrating that site-isolated amine and phosphotungstic acid groups were loaded on mesoporous silica, 6 but the Brønsted acidity of HPAs and the base property of the host were suppressed by each other. Other bifunctional HPAs had been prepared using layered double hydroxides as the base source and HPAs as the acidic one.…”

Facile preparation of bi-functional iron doped mesoporous materials and their application in the cycloaddition of CO2

“…Therefore, it is still a great challenge to effectively inhibit the interaction between the two active sites. The preparation of organic-inorganic hybrid materials by multistep post-modification, such as grafting of acidic and basic sites by the means of H 2 SO 4 /NH 3 treatment or ion exchange, is an effective method to solve this problem [26][27][28] . Although the aforementioned strategies are interesting, they still have obvious shortcoming of complicated preparation process association with the use of toxic and corrosive reagents, along with the unsatisfactory catalytic performance.…”