Electrochemically assisted production of biogenic palladium nanoparticles for the catalytic removal of micropollutants in wastewater treatment plants effluent

•Adsorption of palladium on microorganisms before the exposure to H2 leads to smaller nanoparticles.•Steered production of bio-Pd nanoparticles with H2 produced in situ by an electrochemical cell.•Highly catalytically active bio-Pd nanoparticles obtained at a low H2 flow rate.•Removal of fluorinated antibiotics by bio-Pd nanoparticles in secondary treated municipal wastewater.•High removal efficiencies (> 90%) were obtained for halogenated compounds.