With the global energy transition and the pursuit of carbon neutrality, the development of green and sustainable energy technologies has become an important focus for both academia and industry [1]. Hydrogen energy, featuring high gravimetric energy density and zero carbon emissions at the point of use, is widely regarded as a promising secondary energy carrier [2]. Among various hydrogen production routes, water electrolysis has attracted particular attention because it can enable clean hydrogen generation using water as the sole feedstock. The U.S. Department of Energy (DOE) has identified water electrolysis as a key pathway and set a target to reduce the cost of clean hydrogen to approximately 1 USD kg⁻¹ by 2030–2031[3]. However, current costs remain significantly higher, mainly due to the reliance on noble-metal catalysts and energy losses associated with reaction overpotentials, which limit efficiency and large-scale deployment.
To address these challenges, energy-efficient catalysts and electrolysers are needed to reduce external energy input and avoid reliance on noble metals. In recent years, technologies harvesting motion - piezocatalysis and piezo-assisted electrocatalysis - have attracted increasing interest.[4]. One promising material to combine promising piezoelectric and electrocatalytic properties is MoS₂ [5]. However, while preliminary results have shown promise, developing scalable coatings of MoS2 that remains piezoelectric (and thus able to undergo piezocatalysis) remains challenging.
In this presentation I will discuss our new technique to exfoliate MoS2 combining green solvents and shear mixing. In contrast to prior reports, we obtain few-layered MoS2 platelets with micron-scale lateral size that demonstrate marked piezoelectric properties. We attribute the observation of this piezoelectricity to the significant inter-layer shear induced during shear mixing. The use of this process enables a low tafel slope of 110 mV dec-1, compared to 310 mV dec-1 for conventionally exfoliated materials.