Titanium metal–organic frameworks (Ti‐MOFs), as an appealing type of artificial photocatalyst, have shown great potential in the field of solar energy conversion due to their well‐studied photoredox activity (similar to TiO2) and good optical responsiveness of linkers, which serve as the antenna to absorb visible‐light. Although much effort has been dedicated to developing Ti‐MOFs with high photocatalytic activity, their solar energy conversion performances are still poor. Herein, we have implemented a covalent‐integration strategy to construct a series of multivariate Ti‐MOF/COF hybrid materials PdTCPP⊂PCN‐415(NH2)/TpPa (composites 1, 2, and 3), featuring excellent visible‐light utilization, a suitable band gap, and high surface area for photocatalytic H2production. Notably, the resulting composites demonstrated remarkably enhanced visible‐light‐driven photocatalytic H2evolution performance, especially for the composite 2 with a maximum H2evolution rate of 13.98 mmol g−1 h−1(turnover frequency (TOF)=227 h−1), which is much higher than that of PdTCPP⊂PCN‐415(NH2) (0.21 mmol g−1 h−1) and TpPa (6.51 mmol g−1 h−1). Our work thereby suggests a new approach to highly efficient photocatalysts for H2evolution and beyond.
It has been rarely reported the morphological control of derivatives of metal‐organic frameworks (MOFs) in hydrothermal conditions for photocatalytic applications. We report here a family of highly efficient composite photocatalysts composed of terephthalic acid/terephthalate (TPA) ligand and TiO2with various morphologies (e. g., nanoparticles, nanosheets, and nanorods). The composites are synthesized by a simple one‐step hydrothermal method in various solvents (i. e., H2O, HF, H2SO4, HCl, and HNO3) using Ti‐based MOF (MIL‐125(Ti)) as precursor. The formation mechanism of composite materials with different morphological features is discussed. Impressively, the composite of TiO2nanoparticles/TPA synthesized using H2O as solvent under hydrothermal condition exhibits the highest photocatalytic H2activity among the studied materials, with a photocatalytic H2production rate of 6.38 mmol g−1 h−1, which is approximately 7.5‐fold higher than pure TiO2(Degussa, P25) and prominent apparent quantum efficiency (AQE) of 65 % at 365 nm. Furthermore, the mechanism of boosted photocatalytic H2production is discussed.
more » « less- NSF-PAR ID:
- 10401201
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 29
- Issue:
- 21
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Titanium metal–organic frameworks (Ti‐MOFs), as an appealing type of artificial photocatalyst, have shown great potential in the field of solar energy conversion due to their well‐studied photoredox activity (similar to TiO2) and good optical responsiveness of linkers, which serve as the antenna to absorb visible‐light. Although much effort has been dedicated to developing Ti‐MOFs with high photocatalytic activity, their solar energy conversion performances are still poor. Herein, we have implemented a covalent‐integration strategy to construct a series of multivariate Ti‐MOF/COF hybrid materials PdTCPP⊂PCN‐415(NH2)/TpPa (composites 1, 2, and 3), featuring excellent visible‐light utilization, a suitable band gap, and high surface area for photocatalytic H2production. Notably, the resulting composites demonstrated remarkably enhanced visible‐light‐driven photocatalytic H2evolution performance, especially for the composite 2 with a maximum H2evolution rate of 13.98 mmol g−1 h−1(turnover frequency (TOF)=227 h−1), which is much higher than that of PdTCPP⊂PCN‐415(NH2) (0.21 mmol g−1 h−1) and TpPa (6.51 mmol g−1 h−1). Our work thereby suggests a new approach to highly efficient photocatalysts for H2evolution and beyond.
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