Ondřej Havelka

1. In contemporary business environments characterized by regulatory complexity and geopolitical volatility, innovation management has become deeply embedded in institutional structures that shape ...

The presence of persistent pollutants in water poses a severe environmental threat, driving an urgent need for efficient and eco-friendly remediation strategies. In response, the scientific community is increasingly focused on developing catalytic processes that maximize efficiency while minimizing environmental impact. In this context, we introduce recyclable catalysts based on NiPd nanoparticles (NPs) that feature tunable phase distributions and compositions. By varying Pd doping levels through Reactive Laser Ablation in Liquids (RLAL), we precisely control the catalytic and magnetic properties of these NPs. Notably, a nanocatalyst featuring the NiPd alloyed phase exhibits exceptional catalytic performance, achieving a turnover frequency of 3680 h⁻¹ and 98.5% selectivity in the model transformation of 4-nitrophenol into 4-aminophenol. Additionally, it demonstrates remarkable efficiency in the chemoselective hydrogenation of various nitroarenes to functionalized anilines under mild conditions (atmospheric H₂ pressure, 33 ºC). Furthermore, the synergistic properties arising from the internal structure of these NPs allow them to surpass the performance of nanocatalysts made from their monometallic counterparts and simple mixtures. Overall, this study represents a significant advancement in the precise control of nanocatalyst synthesis and their associated physicochemical properties, paving the way for more efficient redox catalytic protocols, including industrially demanding hydrogenation reactions.

Freshwater scarcity remains a global challenge, often exacerbated by oil contamination. The current study tackles this issue by cleaning oily wastewater while removing its dissolved organic pollutants with PVDF-OH Ag/TiO_x sustainable nanocomposites.

Traditionally, the synthesis of nanomaterials in the ultra-small size regime (1–3 nm diameter) has been linked with the employment of excessive amounts of hazardous chemicals, inevitably leading to significant environmentally detrimental effects. In the current work, we demonstrate the potential of laser fragmentation in liquids (LFL) to produce highly pure and stable iron ultra-small nanoparticles. This is carried out by reducing the size of carbonyl iron microparticles dispersed in various polar solvents (water, ethanol, ethylene glycol, polyethylene glycol 400) and liquid nitrogen. The explored method enables the fabrication of ligand-free iron oxide ultra-small nanoparticles with diameter in the 1–3 nm range, a tight size distribution, and excellent hydrodynamic stability (zeta potential > 50 mV). The generated particles can be found in different forms, including separated ultra-small NPs, ultra-small NPs forming agglomerates, and ultra-small NPs together with zero-valent iron, iron carbide, or iron oxide NPs embedded in matrices, depending on the employed solvent and their dipolar moment. The LFL technique, aside from avoiding chemical waste generation, does not require any additional chemical agent, other than the precursor microparticles immersed in the corresponding solvent. In contrast to their widely exploited chemically synthesized counterparts, the lack of additives and chemical residuals may be of fundamental interest in sectors requiring colloidal stability and the largest possible number of chemically active sites, making the presented pathway a promising alternative for the clean design of new-generation nanomaterials.