Influences of Partial Destruction of Ti‐MOFs on Photo(electro)catalytic H2 Evolution by Dominating Role of Charge Carrier Trapping over Surface Area

Abstract

AbstractThe design of water‐stable photo and electrocatalysts of metal–organic frameworks (MOFs) for its promising catalytic applications at long‐term irradiations or persisted current loads is extremely necessary but still remains as challenging. A limited number of reports on Ti‐MOF‐based catalysts for water splitting are only available to explain and understand the correlation between the nature of materials and MOFs array. Herein, spherical Ti‐MOFs and corresponding partially annealed hollow core–shell Ti‐MOFs (Ti‐MOF/D) are designed and the correlation with their photo(electro)catalytic water splitting performance is evaluated. The switchable valence state of Ti for the Ti‐MOF as a function of molecular bonding is the possible reason behind the observed photocatalytic hydrogen generation and light‐harvesting ability of the system. Besides, the defect state, solid core–shell mesoporous structure, and active sites of Ti‐MOF help to trap the charge carriers and the reduction of the recombination process. This phenomenon is absent for hollow core–shells Ti‐MOF/D spheres due to the rigid TiO2 outer surface although there is a contradiction in surface area with Ti‐MOF. Considering the diversity of Ti‐MOF and Ti‐MOF/D, further novel research can be designed using this way to manipulate their properties as per the requirements.