Role of ZnO in ZnO Nanoflake/Ti₃C₂ MXene Composites in Photocatalytic and Electrocatalytic Hydrogen Evolution

Abstract

Herein, we report a simple hydrothermal synthesis of ZnO-Ti3C2 MXene nanocomposites with a varying wt % of ZnO to exploit the synergistic effect of 2D layer structured Ti3C2 and semiconductor ZnO for photocatalysis and electrocatalysis applications. A systematic study on the efficiency of ZnO-Ti3C2 nanocomposites toward the degradation of organic pollutants (dyes and pharmaceuticals) and the hydrogen evolution reaction (HER) is demonstrated. Among the developed nanohybrid catalysts, the ZnO-Ti3C2 composite with 10 wt % ZnO (MXZnO-10) showed the highest photodegradation efficiency of 76.4% within 10 min of the reaction and 99.2% in 60 min for methylene blue (MB) dye. The synergistic interactions between 2D layered Ti3C2 and ZnO improved the lifetime of electrons and holes by reducing the recombination rate. The uncombined electrons and holes facilitated the effective degradation of the MB dye. The ZnO-Ti3C2 nanocomposite with 5 wt % ZnO (MXZnO-5) showed excellent HER performance and exhibited an overpotential of 495 mV at 10 mA/cm2 with a Tafel slope of 108 mV/dec. This work widens the application range of transition metal oxide–MXene composites, providing potential substitute materials for photocatalysis and electrocatalysis applications.

Synthesis of AgBr/Ti3C2@TiO2 ternary composite for photocatalytic dehydrogenation of 1,4-dihydropyridine and photocatalytic degradation of tetracycline hydrochloride

“…Two peaks appear at the binding energies of 281.6 eV and 288.8 eV, corresponding to the Ti-C bond and the C-F bond, respectively. 43,45 In addition, the O 1s XPs spectrum showed two distinct peaks at 532.2 eV and 530.3 eV (Fig. 5D), the highest peak at 530.3 eV usually represent the lattice oxygen in TiO 2 , which also indicated that TiO 2 was successfully grown in situ on Ti 3 C 2 .…”

“…In comparison with pure AgBr, with an increase of Ti 3 C 2 @TiO 2 content, the light absorption ability of the composites gradually increases. 45,56 The fast charge transfer properties of the prepared materials were analyzed by PL spectroscopy. As shown in Fig.…”

Synthesis of ZnO Nanorod-Decorated Graphene Oxide for Application in Dental Resin Composites

“…The obtained UV–vis absorbance spectra are plotted in Figure A. All these materials exhibit absorbance spectra ranging from 300 to 800 nm, where the absorbance edge appearing at 357 nm indicates the incorporation of ZnO. − More importantly, decreasing the n value of GO n @ZnO from 20 to 3 gradually reduces the light absorbance of particles in the range beyond 400 nm, where GO 3 @ZnO displays the lowest absorbance. Digital photos further confirm these results and GO 3 @ZnO indeed lightens the characteristic color of GO (Figure B), making GO 3 @ZnO as the optimal filler for dental composites.…”

On the reduction of CO2 footprint via selective hydrodeoxygenation by ZnO–Ti3C2Tx catalyst under solvent-free conditions

“…Ti 3 C 2 T x was prepared by immersing 2 g MAX powder slowly in 40 ml of an aqueous solution of 40 wt% HF acid with a magnetic stir bar in a polypropylene beaker and continuously stirring at room temperature for 24 h, as reported in our previous study. 46 The resultant solution of Ti 3 C 2 T x was centrifuged at 4000 rpm and washed several times with DI water to remove AlF 3 and excess HF acid until the pH of the solution reached nearly 7. Finally, the solution was dried overnight in a vacuum oven at 80 °C.…”