Yesilbag, Yasar Ozkan; Tuzluca Yesilbag, Fatma Nur; Huseyin, Ahmad; Salih, Ahmed Jalal Salih; Ertugrul, Mehmet

Two-dimensional (2D) hybrid electrodes combining complementary charge-storage mechanisms represent a promising approach for advanced supercapacitors. In this work, few-layer β-borophene nanosheets were synthesised via a modified Hummers' method and integrated with Ti2NbC2Tx MXene to form 2D/2D hybrid electrodes. Structural characterization confirmed successful borophene exfoliation, MXene–borophene heterostructure formation with locally ordered domains and enhanced ion accessibility. Electrochemical measurements demonstrated that hybrid electrodes significantly outperformed pristine MXene and borophene. The MX-B10 composition exhibited the highest specific capacitance, superior rate capability, and optimal charge-transfer kinetics attributed to synergistic surface-controlled capacitance from borophene and diffusion-assisted ion transport in MXene. A symmetric solid-state supercapacitor (SSSC) assembled with MX-B10 electrodes achieved 54 Wh kg−1 at ~300 W kg−1, retaining 23.2 Wh kg−1 at ~7.6 kW kg−1 with ~97% capacitance retention after extended cycling, These results highlight the potential of borophene–MXene heterostructures for high-performance energy storage applications.

Tabak, A.; Yilmaz, N.; Eren, E.; Caglar, B.; Afsin, B.; Sarihan, A.

The difference in the basal spacing (8.79Å) and a higher mass loss (6.2%) in the temperature range of 200-750°C of naproxen-bentonite (N-bentonite) comparing to that of Unye bentonite (UB) signified the existence of thermally stable organic species in the interlamellar space of the bentonite clay. The asymmetric OCO- stretching band (1607cm-1) of N-bentonite became stronger in the temperature interval of 100-400°C as a result of binding via the CO group of the ligand to exchangeable cation and/or water molecule whereas the OH bending peak of water (1633cm-1) and the CC stretching vibration of aromatic ring (1531cm-1) became weaker on thermal treatment. The effect of ionic strength on the desorption of naproxen species and the related kinetic data revealed that the release mechanism at pH=7.4 is unrestricted diffusion controlled and governed by the repulsive interactions between the bentonite surface and the negatively charged species. The pore structure characteristics of the bentonite samples corresponding to the surface area, pore volume and pore size were determined by using the conventional analysis of the nitrogen adsorption-desorption isotherms.