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Increasing concerns about the vulnerability of the world’s energy supply and the necessity to implement sustainable technologies have prompted researchers to develop high-performance electrocatalysts that are affordable and efficient for converting and storing renewable energy. This article reports a facile approach to fabricating two-dimensional (2D) Ge-decorated h-BN/MoS2 heterostructure nanosheets by self-assembly for multiple electrochemical applications such as supercapacitor and hydrogen evolution reactions. The organization of the physical and chemical links between the germanium modulations on the heterostructure of boron nitride/molybdenum sulphide (Ge/h-BN/MoS2) were facilitated to generate more active sites. Furthermore, the asymmetric supercapacitor of Ge-decorated h-BN/MoS2 amplified the capacitance to 558.53 F g−1 at 1 A g−1 current density and 159.19 F g−1 at 10 A g−1, in addition to a retention rate of 85.69% after 2000 cycles. Moreover, the Ge-decorated h-BN/MoS2 catalyst realized a low over-potential value, with an RHE of 0.57 (HER) at 5 mA/cm2, a Tafel value of ∼204 mV/dec, and long-term electrolysis stability of 10 h. This work may open the door for further investigations on metal-decorated heterostructures, which have a significant potential for both supercapacitor and water-splitting applications.

Lithium iron orthosilicate (LFS) cathode can be prepared via the polyol-assisted ball milling method with the incorporation of carbon derived from eggshell membrane (ESM) for improving inherent poor electronic conduction. The powder X-ray diffraction (XRD) pattern confirmed the diffraction peaks without any presence of further impure phase. Overall, 9 wt.% of carbon was loaded on the LFS, which was identified using thermogravimetric analysis. The nature of carbon was described using parameters such as monolayer, and average surface area was 53.5 and 24 m2 g−1 with the aid of Langmuir and Brunauer−Emmett−Teller (BET) surface area respectively. The binding energy was observed at 285.66 eV for C−N owing to the nitrogen content in eggshell membrane, which provides more charge carriers for conduction. Transmission electron microscopy (TEM) images clearly show the carbon coating on the LFS, the porous nature of carbon, and the atom arrangements. From the cyclic voltammetry (CV) curve, the ratio of the anodic to the cathodic peak current was calculated as 1.03, which reveals that the materials possess good reversibility. Due to the reversibility of the redox mechanism, the material exhibits discharge specific capacity of 194 mAh g−1 for the first cycle, with capacity retention and an average coulombic efficiency of 94.7% and 98.5% up to 50 cycles.