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H2O2 production by photocatalysis has received considerable attention, while using MOF‐based materials as photocatalysts is still less explored. Ligand functionalization of MOFs is a decoration way at the molecular level, which provides the basis for the further modification of MOFs. In this concept, ligand functionalization of MOFs for photocatalytic H2O2 production has been systematically and extensively discussed. The strategies of ligand functionalization include grafting of functional groups (e. g. amino, methoxyl, boron and alkyl) and multiple ligand decoration. Correspondingly, some specific effects are achieved, e. g. improved charge carrier separation, enhanced O2 adsorption and hydrophobicity, which can realize efficient H2O2 production by photocatalysis. Meanwhile, reaction conditions and activities of photocatalytic H2O2 production have also been explicitly introduced in these studies. At last, the future perspectives are proposed. This concept sheds fresh light on the great potential of ligand functionalization of MOFs for photocatalytic H2O2 production. [ABSTRACT FROM AUTHOR]

A series of covalent organic frameworks (COFs) with β‐ketoenamine linkages named TpTt‐COF, TAPT‐COF, and TpPa‐1 were constructed for photocatalytic H2O2 generation in pure water and ambient air under visible light. Among them, TpTt‐COF performed striking H2O2 yield of 2647 μmol L−1, which is 3.5, 17.5, and 176.5‐fold those of TAPT‐COF, TpPa‐1, and bulk g‐C3N4, respectively, attributing to the electron‐deficient trait, short charge diffusion distance, and the narrowest bandgap of TpTt‐COF. Additionally, to achieve the facile recovery, TpTt‐COF was firmly and evenly anchored on melamine sponges (MS) because plenty of amino groups on the surface of MS could be involved in the β‐ketoenamine formation and guide the synthesis of TpTt‐COF on MS. The corresponding H2O2 evolution over this photocatalyst monolith is also respectable and can be well repeated at least four times. This work is quite instructive for photocatalyst construction based on covalent organic frameworks and facile photocatalytic applications. [ABSTRACT FROM AUTHOR]

Porous triazine‐/heptazine‐based carbon nitride (THCN) homojunction with chloride (Cl) doping was synthesized by a simple, one‐step photochemical synthesis route for efficient visible‐light‐driven overall water splitting. The phase ratio of triazine‐based carbon nitride (TCN) and heptazine‐based carbon nitride (HCN), texture and morphology of the THCN isotype junction were finely tuned by varying ultraviolet irradiation time and washing solvents. After washing with acetonitrile, the resulting porous THCN nanosheets with 48 h irradiation contain 21 wt % TCN and 79 wt % HCN units and reveal a significantly improved photocatalytic performance with H2 and O2 production rates up to 7.9 and 4.2 μmol h−1, respectively, about 3.8 times higher than that of THCN prepared by 36 h illumination. The dual‐phase interaction, holey structure, and Cl dopants favor the exposure of active sites, extended visible‐light harvesting, accelerated charge transfer, and enhanced photoreduction ability, thereby improving photocatalytic activity. [ABSTRACT FROM AUTHOR]

Taking advantage of Ni2+ etching on Co-ZIF-L, NiCo layered double hydroxide (NiCo-LDH) with a leaf-like structure and rough surface was achieved and then employed as the structural template to rationally develop a two-dimensional and core–shell NiCo-LDH/ZnIn2S4 composite. Owing to the morphological merits as well as the tight interfacial contact and enhanced contact area between NiCo-LDH and ZnIn2S4 (ZIS), the obtained NiCo-LDH/ZIS favorably enables the interfacial electron transfer to solve the inherent fast photoinduced electron and hole recombination issue of ZIS. Benefiting from this, NiCo-LDH/ZIS with the optimized NiCo-LDH content displayed a high photocatalytic Cr-(VI) reduction efficiency and was able to reduce 30 mg/L Cr-(VI) within only 3 min under visible light, making it a very promising photocatalyst to treat polluted water containing Cr-(VI). [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of biomass‐derived 5‐hydroxyfurfural (HMF) to value‐added 5‐hydroxymethyl‐2‐furancarboxylic acid (HMFCA) is an environmentally friendly process. Here, Ag nanoparticle (NP) supported on TiO2 (Ag/TiO2) materials with different interfacial structures were fabricated via incipient wetness impregnation. In the photocatalytic oxidation of 5‐HMF to HMFCA, low‐temperature reduction (473 K) on Ag/TiO2 could improve the photoinduced charge separation efficiency and promote the reaction due to the "enhanced" localized surface plasmon resonance (LSPR) effects achieved through strong metal–support interaction (SMSI). In particular, 2.5 % Ag/TiO2‐LTR exhibited superior performance with an HMFCA selectivity of up to 96.7 % under visible‐light illumination. In contrast, the photocatalytic efficiency was greatly reduced when the reduction temperature increased to 773 K because of the encapsulation of Ag NPs by a thicker TiOx overlay, which significantly weakened visible‐light harvesting. Overall, these findings offer an efficient methodology for designing interfacial enhanced plasmonic photocatalysts for the valorization of biomass. [ABSTRACT FROM AUTHOR]

Cellulose‐derived carbon (CC) dot‐directed growth of ZnIn2S4 was achieved through hydrothermal treatment of carboxylated cellulose followed by in situ growth of ZnIn2S4 nanosheets. The carbon dots inherited from carboxylated cellulose equip plenty of surface carboxyl groups, which induce the ionic interaction with Zn2+ and In3+ and the guided growth of ZnIn2S4. As a result, the nanosheets of ZnIn2S4 are evenly and intimately grown on the small carbon dots, providing high‐speed channels for charges transfer. In conjunction with the reinforced visible‐light capture and good conductivity of carbon dots, the resultant CC/ZnIn2S4 shows an outstanding photocatalytic activity. As a proof‐of‐concept, visible‐light‐driven 5‐hydroxymethylfurfural oxidation into 2,5‐diformylfuran was conducted. The evolution of 2,5‐diformylfuran over the optimal CC/ZnIn2S4 sample can reach ∼2980 μmol g−1, about 3.4 times that of pristine ZnIn2S4. Additionally, the apparent quantum yield could attain 3.4 % at a wavelength of 400 nm. [ABSTRACT FROM AUTHOR]

[Display omitted] • The whole advancement of MOF-based photocatalysts for H 2 O 2 production was discussed. • Diverse tailoring strategies on MOFs for H 2 O 2 production were summarized in detail. • H 2 O 2 production pathways, activities and reaction conditions were elucidated. • Outlooks on current challenges and emerging opportunities were presented. Photocatalytic synthesis of H 2 O 2 is currently in the spotlight because of its green and sustainable nature, but the construction of photocatalysts with high efficiency is still the key. In this regard, emerging photocatalysts based on metal–organic frameworks (MOFs) have been revitalized for the green synthesis of H 2 O 2 with the various acclaimed merits of MOFs. Therefore, this review provides an insight into the overall progress of MOF-based photocatalysts for H 2 O 2 production through various modification strategies on MOFs, including molecular-level decoration (ligand and metal center decoration, defect and facet engineering), heterostructure construction (C 3 N 4 /MOFs, metal sulfides/MOFs and metal oxides/MOFs) and derivatization (metal oxides/sulfides and carbonaceous materials). Meanwhile, the corresponding pathways (oxygen reduction reaction and water oxidation reaction), performances and reaction conditions for photocatalytic H 2 O 2 production were elucidated. Finally, outlooks on current challenges and emerging opportunities in this research field were presented. We hope this review will inspire and contribute to the future development of both MOF-based catalysts and H 2 O 2 green production. [ABSTRACT FROM AUTHOR]

Flower-like BiOI was decorated by CdS nanodots and followed by the introduction of iodine vacancies (V I) for photocatalytic sodium lignosulfonate (SLS) valorization under visible light. The iodine vacancies could adjust the band configuration, strengthen the light absorption and act as electron traps, while the intimate contact between BiOI and CdS nanodots provides a high-speed channel for charge transfer. As a consequence, the photocatalytic performance of SLS conversion into value-added vanillin was greatly improved over CdS/BiOI-V I compared with those of CdS, BiOI and CdS/BiOI. The highest yield of vanillin is 10.95 mg/g SLS over CdS/BiOI-V I , about 5, 8.7, 1.3 times those of CdS, BiOI, CdS/BiOI, respectively, and exceeding most related photocatalysts reported elsewhere. More significantly, as to the lignin from Masson pine and alkali lignin, the corresponding vanillin yield can reach 7.04 and 6.54 mg/g lignin , respectively, under the same condition, which suggests the great potential and universality for photocatalytic lignin valorization over such CdS/BiOI-V I heterostructure. [ABSTRACT FROM AUTHOR]

[Display omitted] A subtle flower-like MIL-125-NH 2 @BiOI was fabricated by a facile solvothermal method for simultaneously eliminating Cr(VI)/tetracycline mixed pollutants under visible light. The strong interaction between amino in MIL-125-NH 2 and Bi3+ of BiOI promotes the formation of this unique inlaid structure and enables the favorable contact between MIL-125-NH 2 and BiOI, thus accelerating the transfer of charge carriers. Remarkably, MIL-125-NH 2 @BiOI displays a superior activity compared with that of two monomers for the photocatalytic reduction of Cr(VI) and degradation of tetracycline. More significantly, the photocatalytic efficiency can be further boosted in the coexistence of Cr(VI) and tetracycline, which is 1.8 and 1.6 times that of single Cr(VI) and tetracycline, respectively. The synergistic effect between Cr(VI) reduction and tetracycline oxidative degradation can further facilitate the separation of photo-induced electrons and holes, resulting in the improved efficiencies in the Cr(VI)/tetracycline coexistent environment. This work sheds light on that MOF-based photocatalysts possess huge potential for practical environmental remediation. [ABSTRACT FROM AUTHOR]

[Display omitted] Pancake-like TiO 2 (M-TiO 2) derived from the metal-organic framework was inlaid into three-dimensional flower-like BiOI through a facile solvothermal method. M-TiO 2 supplies large surface area and mesoporous structure for attachment and transfer of the substrates and products, while BiOI acts as a photosensitizer to absorb visible light and generates electrons and holes. The distinct structure of M-TiO 2 /BiOI gives a favorable contact between the two monomers, and promotes the transfer of charge carriers. In conjunction with the proper band positions of M-TiO 2 and BiOI, the efficient separation of electron-hole pairs is attained. Benefiting from the above cooperative effects of M-TiO 2 and BiOI, the performance for the vanillin generation from sodium lignosulfonate (SLS) over M-TiO 2 /BiOI composites has a prominent improvement under visible light. Specifically, the yield over optimal M-TiO 2 /BiOI sample is about 5.8 mg/g SLS , obviously superior to that over pristine M-TiO 2 (~1 mg/g SLS) and BiOI (~1.1 mg/g SLS). It is found that h+ and O 2 – play the key role for vanillin generation from sodium lignosulfonate, and the low vanillin generation under UV–vis light sheds light on that OH is an adverse factor. We hoped that this work could inspire the studies on the photocatalytic valorization of biomass using noble metal-free catalysts. [ABSTRACT FROM AUTHOR]

Lignin is abundant and contains a large number of aromatic groups. Herein, Cd x Zn 1-x S photocatalyst with tunable band gap energy was successfully synthesized by using 3-mercaptopropionic acid as a structure tuning additive. Cd x Zn 1-x S can depolymerize alkaline lignin to vanillin by the photocatalytic process. Each gram of alkaline lignin can produce 46.5 mg of vanillin. 2-Phenoxy-1-phenylethanol (PP-ol) and other model compounds were used to understand the depolymerizing process of lignin. Fine tuned Cd x Zn 1-x S can effectively cleave the C β -O-4 bond existed in PP-ol under simulated sunlight. The highest conversion of PP-ol was 89.5% with phenol and acetophenone yields of 66.2% and 33.5%, respectively. The mechanism studies confirm that the C α -H in PP-ol and lignin is firstly dehydrogenated to form C α radical intermediates, and then the photogenerated electrons break the adjacent C β -O bond. This research provides a new strategy to prepare valuable chemicals by virtue of renewable biomass and simulated sunlight. [ABSTRACT FROM AUTHOR]

The delicate design of photocatalyst monoliths is of great significance for the practical applications of artificial photocatalysis. An in-situ synthesis to prepare ZnIn 2 S 4 /cellulose foam was developed. Cellulose is dispersed in a highly concentrated ZnCl 2 aqueous solution to prepare Zn2+/cellulose foam. Zn2+ ions are pre-anchored by hydrogen bonds on cellulose and become in-situ sites for synthesizing ultra-thin ZnIn 2 S 4 nanosheets. This synthesis method makes ZnIn 2 S 4 nanosheets and cellulose tightly bound and prevents ZnIn 2 S 4 nanosheets from stacking in multiple layers. As a proof of concept, the prepared ZnIn 2 S 4 /cellulose foam exhibits a favorable performance for photocatalytic reduction of Cr(VI) under visible light. By adjusting the concentration of zinc ions, the optimal ZnIn 2 S 4 /cellulose foam is capable to completely reduce Cr(VI) in 2 h and the photocatalytic activities show no decrease after 4 cycles. This work could inspire people to build floating cellulose-based photocatalysts via in-situ synthesis. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Core-shell Bi-MOF@BiOX is fabricated by a one-pot solvothermal strategy. • The competitive coordination effect to Bi3+ makes BiOX and Bi-MOF contact closely. • Bi-MOF@BiOX has nice activities on Cr(VI), tetracycline and o-nitrophenol removal. • For above reactions, more than 13, 7, 5-time enhancements of activity are achieved. • Enhanced activities are observed for the treatment of mixed pollutants. Core-shell Bi-MOF@BiOX (X = I, Br and Cl) hybrids were fabricated by a one-pot solvothermal strategy via regulating the concentration and type of halogen ions in the Bi-based CAU-17 synthesis. By virtue of the competitive coordination effect to Bi3+ between CAU-17 and BiOX, CAU-17 was converted into another Bi-MOF with similar structures and compositions. Moreover, Bi3+ plays the role of "bridge" and endows an intimate interface contact between BiOX and the Bi-MOF, which immensely expedites the charge and mass transportation. The obtained Bi-MOF@BiOX hierarchical heterostructures were applied to photocatalytic elimination of solo and mixed pollutants (Cr(VI)/tetracycline and Cr(VI)/o-nitrophenol), and exhibited favorable performances. Choosing Bi-MOF@BiOI as a typical example, the corresponding performances for Cr(VI) reduction, tetracycline and o-nitrophenol degradation in their solo systems are 14, 10, 8 times higher than those of CAU-17, and 13, 7, 5 times higher than those of BiOI under visible light, respectively. Of note, the above photocatalytic performances could be further improved in the coexisting environment of Cr(VI) and tetracycline or o-nitrophenol, which is attributed to the elevated charge separation efficiency caused by the timely consumption of photo-excited electrons and holes. This work gives some insights into the delicate design of MOF photocatalysts and their applications in environmental restoration. [ABSTRACT FROM AUTHOR]

Photocatalytic H 2 O 2 production by reducing O 2 has drawn great interest, but most reactions were conducted in pure O 2 which requires extra energy input. Here, TpPa-1 was facilely decorated by ZnIn 2 S 4 nanosheets for H 2 O 2 production in ambient air under visible light. Profiting from the hierarchical heterostructure, efficient visible-light absorption and O 2 capture of ZnIn 2 S 4 /TpPa-1, an H 2 O 2 yield of 516 μmol·L−1 was obtained with 2 h irradiation, which is 3.0 and 3.9 times those of blank TpPa-1 and ZnIn 2 S 4 , respectively. The intimate interface contact between ZnIn 2 S 4 and TpPa-1 also contributes to the performance improvement. It is noted that the photocatalytic H 2 O 2 formation over ZnIn 2 S 4 /TpPa-1 hybrids experienced an indirect reduction of O 2 that ·O 2 - served as the key intermediate. Additionally, the reactions under different atmospheres and ethanol concentrations demonstrate that both O 2 and ethanol play important roles in the efficient evolution of H 2 O 2. This work could enlighten the heterostructure construction and (photo)catalytic H 2 O 2 production based on covalent organic frameworks. [Display omitted] • ZnIn 2 S 4 /TpPa-1 was first constructed for photocatalytic H 2 O 2 evolution in air. • The H 2 O 2 yield is 3 and 3.9 time-enhancement than those of ZnIn 2 S 4 and TpPa-1. • Efficient visible-light absorption and O 2 capture lead to the high activity. • The H 2 O 2 formation over ZnIn 2 S 4 /TpPa-1 undergoes an indirect reduction of O 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • Oxygen vacancies-rich Bi 2 MoO 6 nanoflakes were facilely anchored on MIL-121. • The oxygen vacancies can highly accelerate the charges transfer and separation. • Vo-BMO/M is more efficient than Bi 2 MoO 6 , MIL-121 and Bi 2 MoO 6 /MIL-121. • Vo-BMO/M can efficiently photocatalytic removal of mixed Cr(VI)/2-nitrophenol. Oxygen vacancy-rich Bi 2 MoO 6 nanoflakes were uniformly anchored on cuboid MIL-121 via benign solvothermal and thermal-reduction methods. Benefiting from the efficient light capture and rich electron traps triggered by oxygen vacancies, intimate interface contact and intrinsic heterostructure, the enhanced separation and transportation rates of photo-induced charge carriers are achieved. Consequently, Bi 2 MoO 6 /MIL-121 with rich oxygen vacancies performs excellent photocatalytic activities, which are 4.8, 7.1, 1.4 times higher for Cr(VI) reduction, and 6.1, 5.4, 1.2 times higher for 2-nitrophenol degradation compared with those of Bi 2 MoO 6 , MIL-121 and Bi 2 MoO 6 /MIL-121 without oxygen-vacancies, respectively. Furthermore, thanks to the timely consumption of photo-induced electrons and holes by Cr(VI) reduction and 2-nitrophenol degradation, respectively, the corresponding photocatalytic efficiencies are further boosted in their coexistent environment. This work would enlighten the design of metal-organic framework-based (photo)catalysts for the treatment of complicated pollution. [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]

• This work reports highly crystalline S-doped CNNTs with tunable geometry. • S-CNNTs-20 exhibit an enhanced visible-light photocatalytic N 2 fixation rate. • High crystallinity and S-N coordination firmly stabilize the surface N in S-CNNTs-20. • The synergistic effect is due to high crystallinity, S dopant and holey tubular form. Highly crystalline carbon nitride nanotubes doped with sulfur (S-CNNTs) were obtained from a facile co-polymerization of thiourea and melamine precursors. The geometry, crystallinity and the doped S content in CNNTs can be fine-tuned by varying the content of thiourea. Under the addition of 20 wt% thiourea, the resulting highly condensed S-CNNTs have a diameter of around 20 nm with mesopores on the tube wall, presenting an optimal visible light photocatalytic ammonia yield rate of 0.64 mM g cat –1h−1 with an apparent quantum efficiency of 5.65% at 420 nm. The surface N atoms in the optimal photocatalyst can be firmly stabilized due to the increased crystallinity and S-induced coordination. The high crystallinity and one-dimensional mesoporous structure promote the electron transfer along the longitudinal dimension, facilitate mass transport and extend visible light harvesting. The mesoporous nanotubes favor the exposure of S dopant active sites for the chemisorption and activation of nitrogen molecules. Moreover, the photoreduction ability is improved due to the upshifted conduction band level after S doping. The designed structure maximizes the utilization of the synergistic effect, thereby improving the photocatalytic activity. This work may provide a reliable and promising way to regulate the morphology and electronic structure of tubular CN for highly efficient photocatalysis via a nonmetal doping approach. [ABSTRACT FROM AUTHOR]

In recent years, organic-inorganic composites have aroused considerable attention due to their tunable properties, where cellulose tailored semiconductors for artificial photocatalysis are typical examples. In virtue of the unique fibrous structure and abundant surface functional groups, cellulose employed in the design of photocatalysts could endow good hydrophilicity, dispersity, stability, high porosity, conductivity, large surface area and even unexpected morphologies. In this review, the modification strategies of cellulose to semiconductors (function as assistants and sacrifice as bio-templates), diverse monoliths (films, gels and textiles) and their photocatalytic applications (contaminants treatment and H 2 production) are summarized in detail. In addition, the challenges and outlook of semiconductor/cellulose photocatalysts are also discussed. • Cellulose tailored semiconductors for photocatalysis were summarized in detail. • Two strategies including cellulose as assistant and bio-template were introduced. • Diverse semiconductor/cellulose photocatalyst monoliths were depicted. • Various photocatalytic applications over semiconductors/cellulose were described. [ABSTRACT FROM AUTHOR]

Ultrathin ZnIn 2 S 4 (ZIS) nanosheets were coated on g-C 3 N 4 (CN) nanotubes to form CN@ZIS heterojunction as a high-performance photocatalyst for Cr(VI) reduction. Well-dispersed ZIS nanosheets on CN nanotubes favor the better utilization of light and the hierarchical pores promote the mass diffusion. Additionally, such in-situ growth of ZIS on CN nanotubes enables the formation of intimate interfacial contact between them and the obtained CN@ZIS displays a low recombination rate of photo-generated electron-hole pairs compared to the pristine CN and ZIS. Benefiting from these structural and compositional advantages, CN@ZIS exhibits a satisfactory photocatalytic Cr(VI) reduction efficiency and can reduce 30 mg/L Cr(VI) within 10 min (catalyst loading: 1 mg/mL) under visible-light irradiation. Such excellent performance makes CN@ZIS great potential in photocatalysis. [Display omitted] • ZnIn 2 S 4 nanosheets are grown on g-C 3 N 4 nanotube to form CN@ZIS heterojunction. • CN@ZIS exhibits structural and compositional advantages. • CN@ZIS exhibits excellent photocatalytic Cr(VI) reduction performance. [ABSTRACT FROM AUTHOR]

• BiOI/MIL-121 photocatalyst is constructed by a facile hydrothermal method. • BiOI/MIL-121 performs excellently for tetracycline degradation under visible light. • Free carboxyl in BiOI/MIL-121 can adsorb tetracycline through hydrogen bond. A series of BiOI/MIL-121(Al) hybrid photocatalysts has been prepared by a facile hydrothermal method. Two-dimensional BiOI sheets are intimately anchored on rod-like MIL-121 due to the electrostatic and coordination effects between Bi3+ and carboxyl. The BiOI/MIL-121(Al) hybrid exhibits favorable performances for visible-light-driven degradation of tetracycline. The degradation performance of the optimal sample BM-20 is more than twice as that of pure BiOI. Apart from the close contacts between BiOI and MIL-121, the hydrogen bond induced by carboxyl in MIL-121 promotes the adsorption of tetracycline, which is also conducive to the photocatalytic degradation process. Moreover, results show that photo-induced holes and superoxide radicals are both the main active species for the photocatalytic degradation of tetracycline over BiOI/MIL-121 composites. This work would inspire the materials design with specific functional groups for efficient (photo)catalytic reaction. [ABSTRACT FROM AUTHOR]