The development of cost-effective and high-performance electrocatalysts for water oxidation has attracted intense research interest. It was reported recently that the interface between the amorphous and crystalline phases plays a significant role in the electrocatalytic activity of transition metal compounds. It was reckoned therefore that an increase in the density of the crystalline–amorphous phase boundary would enhance the electrochemical water oxidation on the catalyst. In this work we develop a new and facile strategy for inducing high density crystalline–amorphous phase boundaries via selective fluorination surface doping. This resulted in excellent characteristics of the engineered material for electrochemical water splitting. An initial computational simulation is carried out to design the crystalline–amorphous phase boundary material and an experimental verification follows for demonstration and optimization of the impact of surface doping. We conclude that the engineering of the interface using this facile and cost-effective strategy maximizes the crystalline and amorphous phases of metal–metalloids, which can be used to fabricate low-cost and efficient electrocatalysts for water oxidation.

It has recently been demonstrated that the OER activity of transition metal sulfides (TMSs) could be enhanced by the introduction of a thin amorphous layer on a pristine surface. We report here a novel strategy to enhance the OER by developing cobalt nickel sulfide (Co_xNi_1−xS₂, CNS) with a high density of crystalline and amorphous phase boundaries. Electrochemical activation (ECA) can partially amorphize hollow CNS nanoparticles derived from surface-selective sulfidation. The ECA-treated CNS (ECA-CNS) electrocatalyst, which is comprised of CNS nanodots separated by thin amorphous layers, shows high densities of crystalline and amorphous phase boundaries. This catalyst shows superior OER catalytic performance with a current density of 10 mA cm⁻² at a small overpotential of 290 mV, a low Tafel slope of 46 mV dec⁻¹, a high mass activity of 217 A g⁻¹, a high turnover frequency of 0.21 s⁻¹ at an overpotential of 340 mV, and excellent stability in alkaline media.

The proton exchange membrane water electrolysis (PEMWE) powered by renewable electricity offers a facile route for clean hydrogen production. The oxygen evolution reaction (OER) at the anode plays a major role in affecting the overall device efficiency due to its sluggish OER kinetics. Thus, it remains a challenge to develop robust and active catalysts for OER in acid media for efficient PEMWE. Currently, iridium (Ir)‐based materials, such as mono‐ and multimetallic Ir, Ir‐based oxides, pyrochlore iridate oxides, and Ir‐based perovskites, are the most promising OER catalysts in acid media for PEMWEs. Extensive research has been conducted to enhance the specific activity of Ir species to make cost‐effective. The present review aims to provide the recent progress on addressing the long‐term durability issue of Ir‐based catalyst for OER in acidic conditions, aspiring to inspire the researchers to design highly efficient and stable Ir‐based catalysts. Moreover, the detailed OER mechanism along with the dissolution nature of Ir species is discussed and summarized. Finally, the status, challenges, and prospects for the development of Ir‐based OER catalysts are discussed.

Poly-(dimethylsiloxane) (PDMS) has been used as a negative friction layer in triboelectric nanogenerators (TENGs) owing to its high electronegativity and flexibility. With the advantage of PDMS, the design of various materials to further enhance the energy output of a PDMS-based TENG system have been suggested for practical applications. Herein, we report a high-efficiency PDMS-based TENG wherein surface-modified carbon nanotubes (SMCs), fabricated by one-step pulsed laser ablation, were used as a PDMS additive. SMCs possess oxygen-rich functional groups on the surface that enhance their permittivity and dispersibility in PDMS. Consequently, improvements in the triboelectric performance and capacitance of an SMC-PDMS-based TENG device (SMC-PDMS) were observed, owing to the synergistic effects of the enhanced permittivity and dispersibility of SMCs. Compared to a pristine PDMS-based TENG, SMC-PDMS containing 0.05 wt% SMCs showed an output voltage of 382.12 V and a current of 29.44 μA, which correspond to 170% and 243% enhancements, respectively. In addition, a facile radio frequency plasma treatment was performed to further improve the performance of SMC-PDMS, resulting in an output voltage of 414.63 V, a current of 40.03 μA, and a power density of 7.69 W m⁻².