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In this study, the effective removal of three major micropollutants (e.g., propranolol hydrochloride, 1-naphthylamine, and 2-naphthol) from water is investigated using defected UiO-66 and functionalized derivatives as adsorbents. The defects in UiO-66 are induced using two distinct strategies. The first one involves a process of selectively thermolyzing labile linkers, leading to the creation of a hierarchical mesoporous framework (HP-UiO-66). The second technique employs monocarboxylic acid modulator, such as acetic acid (AA) or trifluoroacetic acid (TFA), which is coordinated with the Zr-clusters during synthesis and removed upon activation, resulting in the creation of defective UiO-66 structures. The influence they have on structural features of metal–organic framework (MOF) nanocrystals is compared to the ideal nonmodulated UiO-66 MOF. The samples are fully characterized by powder X-ray diffraction (PXRD), scanning electron microscope (SEM), Brunauer–Emmett–Teller surface area analyzer (BET), and thermogravimetric analysis (TGA). Their effectiveness as adsorbents for the elimination of 1-naphthylamine, propranolol hydrochloride, and 2-naphthol from water is examined. The thermodynamic and kinetic parameters of the adsorption process are determined. Interestingly, among the UiO-66 samples examined, HP-UiO-66 exhibits remarkable adsorption capacities of approximately 743, 602, and 409 mg g–1 for 1-naphthylamine, propranolol hydrochloride, and 2-naphthol, respectively. These values surpass all of the reported adsorbents in the literature. The surface interactions between HP-UiO-66 and the three micropollutants were demonstrated by Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) analyses. This enhancement in adsorption performance is linked to the preferential adsorption mechanism, primarily by binding to coordinatively unsaturated zirconium atoms within the MOF structure. Through this study, an effective method for improving the adsorption capability of MOF-based adsorbents is presented through defects engineering in Zr-based MOFs. These findings open the path for the creation of effective MOF adsorbents for water treatment applications. [ABSTRACT FROM AUTHOR]

Operating the dry reforming reaction photocatalytically presents an opportunity to produce commodity chemicals from two greenhouse gases, carbon dioxide and methane, however, the top-performing photocatalysts presented in the academic literature invariably rely on the use of precious metals. In this work, we demonstrate enhanced photocatalytic dry reforming performance through surface basicity modulation of a Ni-CeO2 photocatalyst by selectively phosphating the surface of the CeO2 nanorod support. An optimum phosphate content is observed, which leads to little photoactivity loss and carbon deposition over a 50-hour reaction period. The enhanced activity is attributed to the Lewis basic properties of the PO43− groups which improve CO2 adsorption and facilitate the formation of small nickel metal clusters on the support surface, as well as the mechanical stability of CePO4. A hybrid photochemical-photothermal reaction mechanism is demonstrated by analyzing the wavelength-dependent photocatalytic activities. The activities, turnover numbers, quantum efficiencies, and energy efficiencies are shown to be on par with other dry-reforming photocatalysts that use noble metals, representing a step forward in understanding how to stabilize ignoble nickel-based dry reforming photocatalysts. The challenges associated with comparing the performance of photocatalysts reported in the academic literature are also commented on. The top-performing dry reforming photocatalysts in the literature rely on the use of precious metals. Here, enhanced photocatalytic dry reforming performance is reported through surface basicity modulation of a Ni/CeO2 photocatalyst, achieved by selectively phosphating the surface of a CeO2 nanorod support. [ABSTRACT FROM AUTHOR]

BACKGROUND Bio‐sourced (natural) organic materials are often chemically and structurally disordered, such that their structure‐property relationships must be explored using model systems. Eumelanin is an interesting candidate among natural organic materials. RESULTS: In this work, the locations of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) energy levels of 5,6‐dihydroxyindole (DHI) and 5,6‐dihydroxyindole‐2‐carboxylic acid (DHICA) building blocks (monomers) of the black‐brown biopigment eumelanin, in film form, are studied. The films are fabricated by the spin‐coating technique (i.e., here indicated as DHI‐ and DHICA‐films), which is sometimes followed by ammonia‐induced solid‐state polymerization (i.e., indicated as AISSP‐DHI and AISSP‐DHICA films), as well as by thermal evaporation (i.e., evaporated DHI and DHICA films). From Ultraviolet photoemission spectroscopy (UPS), we deduced the ionization energies (EI) for all DHI‐ and DHICA‐based films to be in the range of 5.34‐5.56 eV and 5.35‐5.80 eV, respectively. The electron affinities (χE) are measurable using inverse photoemission spectroscopy (IPES) for DHI films (3.80 eV) and both evaporated DHI (4.0 eV) and DHICA (3.9 eV) films. On the other hand, the χE values of DHICA, AISSP‐DHI, and AISSP‐DHICA films are estimated with about 0.5 eV of uncertainty. UV‐visible spectroscopy reveals the preferred chromophoric bands for DHICA, AISSP‐DHICA, and DHI are in the range of 300‐330 nm, while AISSP‐DHI exhibits a broadened UV‐visible absorbance. CONCLUSION: Our study paves the way for the design of suitable metal‐eumelanin interfaces for electronic applications. © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) show promise for achieving a high energy density of 500 W h kg -1 , despite challenges such as poor cycle life and low energy efficiency due to sluggish redox kinetics of lithium polysulfides (LiPSs) and sulfur's electronic insulating nature. We present a novel 2D Ti 3 C 2 Mxene on a 2D graphitic carbon nitride (g-C 3 N 4 ) heterostructure designed to enhance LiPS conversion kinetics and adsorption capacity. In a pouch cell configuration with lean electrolyte conditions (∼5 μL mg -1 ), the g-C 3 N 4 -Mx/S cathode exhibited excellent rate performance, delivering ∼1061 mA h g -1 at C/8 and retaining ∼773 mA h g -1 after 190 cycles with a Coulombic efficiency (CE) of 92.7%. The battery maintained a discharge capacity of 680 mA h g -1 even at 1.25 C. It operated reliably at an elevated sulfur loading of 5.9 mg cm -2 , with an initial discharge capacity of ∼900 mA h g -1 and a sustained CE of over 83% throughout 190 cycles. Postmortem XPS and EIS analyses elucidated charge-discharge cycle-induced changes, highlighting the potential of this heterostructured cathode for commercial garnet LSB development.