Unique properties and potential applications of 2D materials draw much attention for mass production of thin-layer 2D materials. Ball milling exfoliation of 2D materials has been rarely used, in spite of a promising dry phase production method, because of the superficial information in the mechanism and the effect of the operating parameters on the yield, size and thickness. Here, we investigate systematically the ball milling operating parameters in the exfoliation of bulk MoS ₂ in the presence of sodium cholate (SC) as an exfoliant. The yield and dimensions of the exfoliated MoS ₂ nanosheet were monitored by changing the parameters such as the weight ratio of bulk MoS ₂ and SC (SC/MoS ₂ ), the filling ratio in the volume of milling ball and container ( φ ), milling ball size ( d _B ), milling revolution speed ( n _R ), and initial mass of bulk MoS ₂ ( m MoS 2 ). The yield of exfoliation is found to be 95% at the optimum ball milling conditions (SC/MoS ₂ = 0.75, φ = 50%, m MoS 2 = 0.20 g). In addition, yield and size of the exfoliated MoS ₂ were controlled by the conditions of the ball milling. As for the evaluation of the exfoliated MoS ₂ , we developed a novel method by use of the XRD profile to determine the size and thickness of the ball-milled MoS ₂ powder with less than 30% difference from those determined by the well-known absorption method. Finally, the size and thickness of the MoS ₂ nanosheets prepared by ball milling exfoliation were correlated with their electrocatalytic and photoelectrocatalytic activities.

The photoelectrochemical performance of bismuth vanadate (BVO) improved by a thin layer of bismuth ferrite (BFO).

TiO₂ deposition on silicon photocathode enhances its stability and forms an intimate junction with the Au electrocatalyst. Moreover, optimizing the Au loading amount is crucial for maximizing NH₃ production efficiency.

Chalcogenides are promising materials for photoelectrochemical (PEC) water splitting owing to their suitable band gaps, favourable band alignments, and efficient charge transport properties. However, their practical application has been limited by poor stability in aqueous environments, as they are prone to self-oxidation prior to water oxidation. This instability typically necessitates the use of sacrificial agents to scavenge photogenerated holes, thereby restricting long-term device operation and real-world implementation. Here we report a metal-encapsulated PbS quantum dot (PbS-QD) solar cell-based photoelectrode that simultaneously achieves high photocurrent and long-term operational stability for PEC water splitting without sacrificial agents. The optimised PbS-QD-based photoanode delivers a photocurrent density of 18.6 mA cm^-2 at 1.23 V versus the reversible hydrogen electrode in 1.0 M NaOH, retaining 90% of its initial performance over 24 h. These values are comparable to those reported for chalcogenide-based photoelectrodes operating in the presence of sacrificial agents.