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[Display omitted] • 3D-graphene/NH 2 -MIL-125 nanohybrids was engineered using dual-mode bonding of NH 2 -IL. • NH 2 -IL formed π-π connection in IL-3DGr/NM(Ti) and greatly enhanced e-/h+ mobility. • NH 2 -IL formed amide bond in IL-3DGr/NM(Ti) and formed highly active sites of CUS and O V. • IL-3DGr/NM(Ti) exhibited high H 2 O conversion ability to •OH with aid of CUS and O V. • IL-3DGr/NM(Ti) showed ultra-faster C 2 H 4 O degradation rate even under high humidity. The development of metal organic framework (MOF)-based π-π conjugated structures capable of effectively transforming H 2 O from humid air to • OH radicals for VOCs photodegradation is a significant but difficult task. Herein, an amino-ionic liquid (NH 2 -IL) based dual-mode bridging strategy was proposed to connect 3D-graphene with NH 2 -MIL-125 forming IL-3DGr/NM(Ti) nanohybrids for advanced acetaldehyde photodegradation. The rational integration of these components was responsible for: (1) maintaining π-π conjugated electron transport system; (2) generating abundant coordinatively unsaturated sites and oxygen vacancies; (3) increasing surface area of the nanohybrids. With these attributes, IL-3DGr/NM(Ti) demonstrated enhanced charge separation and transportation electrochemical impedance spectroscopy (EIS): 7-times), acetaldehyde adsorption (22 %), light absorption (bandgap: 1.51 eV). The rapid H 2 O adsorption and photoconversion to • OH radicals by IL-3DGr/NM(Ti) enabled it to demonstrate superior CH 3 CHO photodegradation rate under high humidity, surpassing many state-of-the-art photocatalysts by 9 to 187 times under static air conditions and with nearly similar catalyst dosages* (photocatalyst weight and initial acetaldehyde concentration (mg ppm−1) ratio). Interestingly, the IL-3DGr/NM(Ti) photocatalytic activity was enhanced by increasing RH% up-to 80 %. Besides, the nanohybrids demonstrated tremendous stability, with only a 3.9 % decline observed after 5 consecutive-cycles. This strategy provides new prospects to improve the compatibility of graphene/MOF materials for futuristic photoelectrical applications under high humidity. [ABSTRACT FROM AUTHOR]

[Display omitted] • MXene/MOF aerogel with bi-bonding Ti-N/N-Zr was constructed via microwave-assisted construction. • Abundant MOF crystals were grown on MXene surface based on MXene hot-spot effect. • MXene and their tight interface enhanced aerogel light absorption, e –/ h + separation, and radical generation. • MXene/MOF aerogel showed 10–104 times higher k a than state-of-art photocatalysts. • MXene/MOF aerogel realized ∼ 95% TOC removal of acetone and remarkable reusability. Designing MOF aerogels possessing highly efficient photocatalytic performance for VOCs photodegradation is a significant but challenging task. Herein, a microwave-assisted bridging strategy was proposed to construct MXene/MOF aerogel photocatalysts based on the wave-absorbing hot-spots effect of MXene for efficient acetone photodegradation in high humidity. The MXene/MOF aerogel formed abundant and intimate nano-interfaces via N-metal (N-Ti[MXene] and N-Zr[NH 2 -UiO-66(Zr)] bi-bonding under microwave irradiation, which enhanced light absorption, OH/ O 2 − radicals formation, photo-induced electron-hole (e –/ h +) generation, and their separation. Consequently, it exhibited excellent acetone photodegradation (97.3%) in 80% high humidity, with 10–104 times higher apparent rate constants (k*) than those of state-of-the-art photocatalysts. Moreover, MXene/MOF aerogel photocatalyst realized ∼ 95% TOC removal of acetone within 60 min and exhibited remarkable photocatalytic stability after five cycling-runs. Considering these attributes, the newly designed MXene/MOF aerogel photocatalysts have the potential to provide a practical approach for the efficient degradation of VOCs under high humidity conditions. [ABSTRACT FROM AUTHOR]

Construction of highly-active photothermal catalysts featuring merits of high quantum efficiency and superior heat resistance is a great challenge during volatile organic compounds (VOCs) degradation under high humidity. Herein, a facile solvent-induced dimensionality reduction strategy was proposed to engineer a nanosheeted and polycrystalline Cu/Mn-based catalyst (M-Cu/MnO x) having interfacial oxygen vacancies for enhanced photo-thermal catalytic degradation of toluene under highly humid conditions. Unique Cu-mediated δ-MnO 2 /Mn 3 O 4 nanosheets with high surface area exhibited excellent light absorptivity and photogenerated carrier separation efficiency, as well as superior light-driven thermogenesis. It realized ultra-high (92.8%) toluene conversion and deep mineralization (84.4%) under RH = 80% and continuous catalytic reaction (200 h). Its toluene degradation rate exhibited 3.5–71.9 times higher than reported state-of-the-art photothermal catalysts. The newly designed M-Cu/MnO x catalyst provides a promising, low-cost and alternative for the efficient degradation of toluene and other similar VOCs under humid conditions on large-scale operations. [Display omitted] • Cu/MnO x nanosheets with abundant O V are engineered by facile solvent-induced strategy. • Cu/MnO x nanosheets have superior light absorption and photothermal conversion ability. • Photothermal synergism activates O V to achieve low-temperature toluene degradation. • Cu/MnO x displayed 3.5–71.9 times higher toluene degradation rate than reported catalysts. • Cu/MnO x showed excellent long-lasting (∼ 200 h) photothermal catalysis for toluene. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cr-N anchors were pre-load on tubular carbonized N-doped polymer (TCNP). • MIL-101(Cr/Cu) on Cr-TCNP via N-Cr-O interface constructed hydrophobic interface. • Insertion of TCNP and Cu enhanced π-π conjugation and electrostatic interaction between toluene and [TCNP 5 /MIL(Cr/Cu)] N-Cr. • [TCNP 5 /MIL(Cr/Cu)] N-Cr showed 2.9 times higher toluene uptake than MIL-101 at P / P 0 = 0.02. • [TCNP 5 /MIL(Cr/Cu)] N-Cr exhibited 2.1 times higher toluene capacity than MIL-101 under 80% RH. High capacity adsorption of volatile organic compounds (VOCs) in high humidity environment is a crux but challenge for atmospheric VOCs governance. In this work, tubular carbonized N-doped polymers (TCNP) were implanted into MIL-101 via N-Cr-O interface self-assembly, enabling high adsorption for vapor toluene in high humidity. Through mechanical ball milling and carbonization, Cr ions were preloaded on TCNP to form highly dispersed 3–5 nm Cr-N crystallite as anchors for growing MIL-101(Cr/Cu). Newly constructed smaller micropores of 6.8 Å with aromatic rings/N sites at the interface and doped Cu ions in MOF framework synergistically enhanced π-π conjugation and electrostatic interaction for C 7 H 8 molecules. This endowed [TCNP 5 /MIL(Cr/Cu)] N-Cr 2.9 times higher toluene uptake (6.34 mmol/g) at low vapor pressure (P / P 0 = 0.02) and 1.9 times diffusivity under high humidity (60% RH) than that of MIL-101(Cr) at 298 K. The adsorption breakthrough curves for vaporous toluene showed that TCNP@MIL-101(Cr/Cu) exhibited outstandingly higher adsorption equilibrium capacity (2.7 mmol/g) under 80% RH, corresponding to approximately 2–10 times than those of reported state-of-the-art adsorbents under similar conditions. This study provided a novel interface construction strategy for hydrophobic MOF composites, which supplied deeper understanding for VOCs adsorption and promoted MOFs practical application in VOCs capture under humid environment. [ABSTRACT FROM AUTHOR]

Fabrication of broad-spectrum response photocatalysts in a controllable manner that can efficiently utilize solar light as much as possible remains a top priority target yet a challenging task. In this work, a facile approach of synchronous bottom-up growth was employed to construct UCNP/NMIL(Ti) nanohybrids via NH 2 -BDC (NH 2 -MIL-125-ligand) linkage between upconversion NaYbF 4 :Tm3+ nanoparticles (~13-nm) and NH 2 -MIL-125. The ligand sharing integration strategy generated abundant oxygen vacancies and coordinatively-unsaturated-metal sites, efficiently enhanced light absorption, energy-transfer upconversion (UC-PL), photo-induced e -/ h + generation, and their separation (CV, EIS, Photocurrent-density). Consequently, UCNP/NMIL(Ti) exhibited excellent acetaldehyde photodegradation activity, with 12.5–77.0-folds higher rate constants (k a) than those of state-of-the-art photocatalysts under visible light and high humidity. Furthermore, the photocatalytic activity of UCNP/NMIL(Ti) only declined from 96.0% to 92.5% after five cycling-runs, demonstrating its remarkable photo-catalytic stability. Considering these attributes, the current strategy provides an avenue to synthesize efficient UCNPs/MOF composites for widespread usage in a variety of commercial applications. [Display omitted] • Upconversion UCNP/NMIL(Ti) was fabricated by NH 2 -BDC ligand sharing strategy. • Photons upconversion from NIR to UV-Vis and their transfer to NMIL(Ti) was achieved. • UCNP/NMIL(Ti) showed excellent CH 3 CHO NIR degradation performance in high humidity. • UCNP/NMIL(Ti) showed 12.5–77 times higher k a than some state-of-art photocatalysts. • Remarkable reusability and structure stability proved UCNP/NMIL(Ti) practicality. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hollowed TiO 2 @UiO-66 composite having Zr/Ti inter-penetrated interface was built. • Zr/Ti inter-penetrated interface promoted the separation efficiency of carriers and shortened the reaction pathway. • Zr/Ti inter-penetration intensified Lewis acidity and thus promoted catalytic activity of the composite. • H-ZrTiO 2 @U6N showed ∼100 times increase of reaction rate for aldehyde degradation. • H-ZrTiO 2 @U6N showed an excellent structural stability and photo-activity durability. Well-defined construction of interface compatibility is greatly helpful to overcome interface attenuation, featuring the combined advantages from different photo-catalysts. Herein, we proposed "Interfacial metal interpenetration" strategy to engineer a novel hetero-structural TiO x @UiO-66-NH 2 photocatalyst (H-Zr 0.1 Ti 0.9 O 2 @U6N) having core-shell characters and well-organized interface compatibility for acetaldehyde (ALD) degradation. XRD refinement and XPS showed that Zr and Ti clusters were proved to induce the lattice expansion of H-Zr 0.1 Ti 0.9 O 2 and lattice shrink of UiO-66-NH 2 , respectively. This strategy efficiently overcame transmission jam of photo-induced electrons, facilitating the separation efficiency of electron-holes. Furthermore, improved interface compatibility and hollow merits of H-Zr 0.1 Ti 0.9 @U6N jointly expedited the mass transfer of reactants, shortening the "adsorption-catalysis" pathway. Therefore, H-Zr 0.1 Ti 0.9 O 2 @U6N showed about two orders of magnitude increase of catalytic kinetics (195 × 10−3 min-1) compared to H-TiO 2 (0.002 min-1) at 75 % relative humidity (RH), far beyond noble metal modified photo-catalyst Ag@TiO 2 (11.9 × 10−3 min-1). The "Interfacial metal interpenetration" strategy can effectively improve material compatibility and award multiplying effects for different photo-catalysts. [ABSTRACT FROM AUTHOR]

High Catalytic Activity and Stability for CH 3 CHO Degradation. • PANI was dissolved to oligomer by ionic liquid to cross-link with NMIL(Ti) via Ti-N. • PANI oligomer endorsed abundant of defects and Lewis acid sites in IL-PANI/NMIL(Ti). • PANI oligomer promoted light absorption and charge mobility of NMIL(Ti) photo-activity. • Defected interface in NMIL(Ti) dramatically encouraged MOF to adsorb CH 3 CHO. • IL-PANI/NMIL(Ti) showed 4.2 times higher degradation rate for CH 3 CHO than NMIL(Ti). A novel strategy and design for ionic liquid (IL) assisted in-situ grafting of polyaniline (PANI) oligomers in NH 2 -MIL-125 was proposed to synthesize the defect-rich IL-PANI/NMIL(Ti) nanohybrids with an intimate interface for the superior photodegradation of CH 3 CHO. PANI was dissolved into small oligomers with the aid of IL [EMIM]BF 4 and was composited to NH 2 -MIL-125 by a strong interfacial connection through Ti-N bonds (XPS) with high dispersion and large surface area (BET = 1125 m2/g). Characterizations results showed that smart grafting of PANI-oligomers generated abundant defects (3.4-times, ESR) and intensified Lewis acid sites (1.2-times, CO-DRIFT) in IL-PANI/NMIL(Ti) compared to NH 2 -MIL-125. It promoted adsorptive interactions for aldehyde VOCs capturing, which in-turn increased the adsorption rate (k a) of CH 3 CHO. Smart grafting also improved the light absorption of IL-PANI/NMIL(Ti) from 500 to 800 nm, reduced band gap (1.7 eV), increased photo-current density (2.2-folds of pure MOF), enhanced O 2 − and OH radicals generation and improved e − /h+ mobility. As a result, IL-PANI/NMIL(Ti) showed 11.4 and 4.2 times higher k a (0.262 min−1) of CH 3 CHO photodegradation kinetics than PANI and NH 2 -MIL-125, respectively, at 75% relative humidity (RH). The k a of CH 3 CHO degradation was steadily increased with increasing humidity (<80 RH%), indicating that H 2 O from humid air was beneficial for CH 3 CHO degradation. Furthermore, IL-PANI/NMIL(Ti) exhibited the excellent recycling stability compared to NH 2 -MIL-125, as only a 5% decrease in photocatalytic activity was observed after five cycling runs. Considering the excellent photostability and ultrafast photodegradation of CH 3 CHO, the current study opens up new perspectives in fabricating MOFs for a wide-range of practical applications. [ABSTRACT FROM AUTHOR]

• Short-chains PEG is implanted into MIL-101 cage via coordination of –OH with Cr3+. • PEG is proved to form a hydrophobic barrier and raise H 2 O diffusion resistance. • Formed novel pore (11.2 Å) enhances dispersion force to toluene showing high uptake. • PEG restricts H 2 O diffusion in their implanted area but has less effect on toluene. • PEG 5 @MIL-101 shows 3.3 times of toluene working capacity than MIL-101 at 80% RH. Adsorption of volatile organic compounds (VOCs) under high humidity is crucial for metal–organic frameworks (MOFs) in practical applications. To enhance competitive adsorption of VOCs under humidity, polyethylene glycol (PEG) with hydrophobic short-chains was implanted as hydrophobic barrier into MIL-101(Cr). Characterization and simulation results showed that the terminal –OH groups of PEG chains were coordinated with the Cr sites in MIL-101(Cr) and formed a hydrophobic pore (11.2 Å) of "cage-in-cage" geometry. PEG chains significantly hindered the diffusion of water into the MOFs while allowed toluene molecules. The new hydrophobic pores of PEG 5 @MIL-101 enhanced adsorption capacity and diffusivity for toluene by 30.8% (4.68 mmol/g at 1 mbar) and 31.5% (1.88 × 10−2), while decreased adsorption capacity and diffusivity for water by 53.7% and 26.8% compared to primary MOF. Breakthrough curve showed 3.3 times of toluene working capacity on PEG 5 @MIL-101 at 80% RH compared to pristine MIL-101(Cr). [ABSTRACT FROM AUTHOR]