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Mesoporous TiO 2 with regular pancake-like morphology was synthesized by facile calcination of MIL-125 (MIL = Materials of Institut Lavoisier) at different temperatures. The optimal sample MT400 (calcination at 400 °C) is composed of nanoparticles with a size of about 10 nm and mesopores of about 4–12 nm. Its specific surface area can reach up to 174 m2 g−1. In the photocatalytic conversion of sodium lignosulfonate, the yield of vanillin over MT400 is 2.1 mg/g, obviously superior to that over P25 TiO 2 (0.27 mg/g). MT400 with a large specific surface area offers sufficient active sites, and its mesoporous structure provides pathways for the transport of charge carriers and products, giving a satisfactory photocatalytic performance for vanillin generation. It is proved that h+ and ·O 2 − play the key role for vanillin generation from sodium lignosulfonate. This work indicates that MOF-derived metal oxides hold great promise in the application of biomass (photo)catalytic valorization. [Display omitted] • A pancake-like mesoporous TiO 2 was synthesized by the calcination of MIL-125. • MT400 is composed of particles with a size of ca. 10 nm and mesopores of 4–12 nm. • The yield of vanillin over MT400 is 7.7-fold higher than that of P25. • The structure is helpful to the transport of charge carriers, substrates and products. [ABSTRACT FROM AUTHOR]

MIL-101(Cr)@ZnIn 2 S 4 hierarchical heterojunction was delicately designed and fabricated through the in-situ growth of ZnIn 2 S 4 on MIL-101 and electrostatic self-assembly. It is affirmed that the Cr–S interface bonding between MIL-101 and ZnIn 2 S 4 in their composite was established based on the characterization results of X-ray photoelectron spectroscopy, Raman and zeta potential. Thus, a high-speed channel for charges transfer is offered due to the Cr–S bond, intimate interface contact and hierarchical structure of MIL-101@ZnIn 2 S 4 , which largely inhibits the recombination of photo-induced charge carriers and promises a remarkable photocatalytic activity. Choosing visible-light-driven reduction of Cr(VI) as a model, the optimal MIL-101@ZnIn 2 S 4 sample can reduce 95% of Cr(VI) within 30 min, corresponding to a rate constant of 0.107 min−1, which is 2.9-fold compared with blank ZnIn 2 S 4 counterpart (MIL-101 has a negligible performance). Additionally, a conspicuous apparent quantum yield of 9.7% can be achieved at a wavelength of 420 nm. Eventually, to reinforce the practicability of MIL-101@ZnIn 2 S 4 , the composite powders were manufactured as aerogels utilizing bacterial cellulose as a substrate. The MIL-101@ZnIn 2 S 4 aerogel still exerts an enviable performance for photocatalytic reduction of Cr(VI) and stability. This work could inspire the material design and environmental remediation based on MOFs. [Display omitted] • MIL-101@ZnIn 2 S 4 hierarchical heterojunction with Cr–S bonds was delicately designed. • A high-speed channel for charges transfer is presented over MIL-101@ZnIn 2 S 4. • Efficiently photocatalytic reduction of Cr(VI) is achieved over MIL-101@ZnIn 2 S 4. • Aerogel was prepared from powder to improve the practicability of MIL-101@ZnIn 2 S 4. [ABSTRACT FROM AUTHOR]