Tin disulfide (SnS₂) has gained a lot of interest in the field of converting solar energy into chemical fuels in light-assisted electrochemical water splitting due to its visible-light band gap and high electronic mobility. However, further decreasing the recombination rate of electron-hole pairs and increasing the density of active states at the valence band edge of the photoelectrodes were a critical problem. Here, we were successful in fabricating the super-thin SnS₂ nanostructure by a hydrothermal and solution etching method. The super-thin SnS₂ nanostructure as a photo-electrocatalytic material exhibited low overpotential of 0.25 V at the current density of −10 mA·cm⁻² and the potential remained basically unchanged after 1000 cycles in an H₂SO₄ electrolyte solution, which was better than that of the SnS₂ nanosheet and SnS/SnS₂ heterojunction nanosheet. These results show the potential application of super-thin SnS₂ nanostructure in electrochemical/photo-electrocatalytic field.

The mainstream strategy for designing hydrogen electrocatalysts is to adjust their surface electronic structure; however, the conductivity of the electrocatalyst and the synergy with its substrate are still challenges to overcome. In this work, we report a carbon-doped Co-FeS₂/CoS₂ (C/Co-FeS₂/CoS₂) electrode, prepared via a hydrothermal process with carbon cloth (CC) as the substrate and carbon doping. The C/Co-FeS₂/CoS₂ electrode shows excellent catalytic activity in the hydrogen evolution reaction (HER) with an overpotential of 88 mV at a current density of −10 mA∙cm⁻² in 0.5 M H₂SO₄ solution. The Tafel slope is 66 mV∙dec⁻¹. Such superior performance is attributed to the high electrical conductivity of the electrocatalyst and its synergy with the substrate. Our study provides an efficient alternative in the field of electrocatalysis.

Ag₂Te is a novel topological insulator system and a new candidate for plasmon resonance due to the existence of a Dirac cone in the low-energy region. Although the optical response spectrum of Ag₂Te has been studied by theoretical and experimental methods, the plasmon resonance and stability of Co-doped Ag₂Te remain elusive. Here, we theoretically report a new unconventional UV plasmon mode and its stability in Co-doped Ag₂Te. Through density functional theory (DFT), we identify a deep UV plasmon mode within 15–40 eV, which results from the enhanced inter-band transition in this range. The deep UV plasmon is important for detection and lithography, but they have previously been difficult to obtain with traditional plasmon materials such as noble metals and graphene, while most of which only support plasmons in the visible and infrared spectra. Furthermore, we should highlight that the high-energy dielectric function is almost invariant under different doping amounts, indicating that the UV plasmon of Ag₂Te is robust under Co doping. Our results predict a spectrum window of a robust deep UV plasmon mode for Ag₂Te-related material systems.