The development of thermodynamically favourable and stable photocatalysts for solar-driven hydrogen production remains a major challenge in renewable energy research. Herein, first-principles density functional theory (DFT) calculations were employed to investigate the structural, electronic, optical, and photocatalytic properties of zirconium-based transition metal dichalcogenides (TMDCs), including ZrS2, ZrSe2, ZrTe2, Janus ZrSSe and ZrSTe monolayers, and their van der Waals heterostructures. Initial screening using PBE and PBE + U functionals identified the most promising systems, which were subsequently examined using the HSE06 hybrid functional. The selected materials exhibit indirect band gaps of 1.25–1.83 eV, suitable for visible-light absorption, and favourable band-edge positions for photocatalytic water splitting. Among them, the Janus ZrSSe monolayer and the P3-stacked ZrSSe|ZrSSe bilayer show outstanding hydrogen evolution reaction (HER) activity, with ΔG_H values of 0.032 and −0.004 eV and ultralow overpotentials of 32.5 and 3.5 mV, respectively, highlighting their potential for active hydrogen generation.
Moving toward new generations of energy storing systems, e.g. all-solid-state–batteries (ASSBs), it is essential to gain insight into the fundamental mechanisms of the related electrochemical devices. In this regard, development of solid electrolyte interphase (SEI) and its relation with electrolyte properties (HOMO and LUMO) are considered in the present work. The creation of solid electrolyte interface, SEI, poses various positive or negative effects in the cell performance. This study provides a new perspective on the issue, by considering configuration of DOS bands of intercalated/deintercalated electrode material and relation between the Fermi level of the reaction component and the respect of frontier orbitals, i.e. Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO). Consequently, SEI formation on cathode and anode during charge and discharge process is discussed.
This study investigated the conversion of salon hair waste into keratin hydrolysate (KH) and its use as a multifunctional bio-filler in natural rubber (NR) composites for mechanical reinforcement and triboelectric energy harvesting. A four-factor Box–Behnken design was used to evaluate the effects of extraction time, temperature, NaOH concentration, and NaHSO3 concentration on KH protein concentration. The quadratic model was significant (p < 0.001; R2 = 0.910, adjusted R2 = 0.891, predicted R2 = 0.863), although significant lack of fit indicated limitations in describing the experimental response. The selected extraction condition (105 min, 90 °C, 2.0% NaOH, and 0.5% NaHSO3) gave an experimental protein concentration of 17.01 mg/mL compared with a predicted value of 15.14 mg/mL. The recovered KH was characterized by FE-SEM, SDS-PAGE, FTIR, CHNS analysis, solid-state 13C-CP/MAS NMR, and XRD. KH incorporation increased NR hardness and M100, while tensile strength and M300/M100 reached their highest measured values at 5 phr. SEM revealed comparatively more uniform KH distribution at 5 phr and pronounced agglomeration at 10 phr. TGA/DTG showed that KH modified early-stage degradation without substantially altering the principal NR degradation temperature. NR/KH-5 exhibited the highest triboelectric output (78.5 V and 7.2 μA), a maximum power density of 1.16 W/m2, and approximately 95% output retention after 10,000 cycles. Overall, 5 phr KH provided a favorable balance of mechanical reinforcement, filler distribution, and triboelectric performance, demonstrating the potential of hair-derived KH as a multifunctional bio-filler for NR.
Smart ocean systems require underwater sensing networks capable of long-term autonomous operation, low maintenance, and distributed deployment. However, existing nodes remain limited by insufficient power supply, strong environmental interference, and difficult in situ maintenance. Owing to their high efficiency in low-frequency mechanical energy conversion, broad material compatibility, and flexible structural design, triboelectric nanogenerators provide a promising route for underwater energy harvesting and self-powered sensing. This review systematically summarizes recent progress in TENG-based underwater energy harvesting and self-powered sensing. First, the fundamental mechanisms such as contact electrification are discussed, with particular emphasis on the critical roles of encapsulation isolation in stabilizing device output in marine environments. Subsequently, TENG-based ocean current energy harvesting strategies are reviewed, including rigid structures, flexible structures, bioinspired configurations, and large-scale arrayed and networked systems. In addition, representative underwater self-powered sensing applications are summarized, including ocean current velocity sensing, distributed disturbance sensing, and artificial lateral-line sensing. Finally, key challenges are discussed in such as terms of long-term deep-sea durability, and intelligent energy management. Future perspectives are proposed toward the integration of advanced materials, fluid-structure interaction-guided design, and marine blue-energy networks, aiming to promote the transition of TENG-based underwater systems from laboratory demonstrations to long-term ocean deployment.
