Laser‐Induced Reactive Deposition of Nanostructured CoS2‐ and Co2CuS4‐Based Films with Fenton Catalytic Properties.

Highly polymorphic cobalt sulfide represents attractive material because of its unique electronic, optical, magnetic, mechanical and catalytic properties. Pulsed laser irradiation of a solid CoS2 target results in ablation and deposition of thin films on Ta and Cu substrate, which were analyzed using scanning electron microscopy, Raman and FTIR spectroscopy, X‐ray photoelectron spectroscopy, high resolution electron microscopy and electron diffraction. These complementary analyses revealed that the film on Ta consists of the parent cubic CoS2 whereas the film on Cu exhibits a multiphase structure containing the cubic CoS2 and cubic Co2CuS4. The ternary species is known as an active electrode material with relatively high energy density for electrochemical capacitors and proves interdiffusion events at the interface of copper and colliding CoS2 particles. Such facile and one‐step process represents the first example of the Co2CuS4 formation through ablative reactive deposition on unheated substrate and adds to very rare examples of reactive laser deposition of ablated metal sulfides on unheated surfaces. The CoS2‐based films deposited on Ta and the Co2CuS4‐based films deposited on Cu were examined for their catalytic effect in Fenton degradation of methylene blue (MB). Their efficiency to degrade MB is compared and discussed. Laser irradiation of CoS2 allows deposition of nanocrystalline CoS2 on Ta and reactive deposition of Co2CuS4 on Cu substrate. Bimetallic sulfide is formatted via interdiffusion events of hot Co/S particles colliding with Cu atoms which are incorporated into cubic lattice of original CoS2. CoS2 and Co2CuS4 films exhibit catalytic effect in terms of Fenton‐like degradation. [ABSTRACT FROM AUTHOR]