Summary A wide compositional range of Pd‐Ni/Cd on polypyrrole (PPy)‐modified Ti plates (Pd‐Ni/Cd/PPy/Ti) was fabricated via electrochemical deposition. The hydrogen absorption properties of the prepared Pd‐Ni/Cd/PPy/Ti electrodes were evaluated using cyclic voltammetry and chronoamperometry in acidic media. The optimal Pd36‐Ni7/Cd57/PPy/Ti electrode achieved a hydrogen storage capacity of 331.3 mC cm−2 mg−1 and an H/Pd ratio of 0.77. The enhancement of the hydrogen storage was attributed to a synergistic effect between the Pd‐Ni/Cd catalysts. The surface morphology, crystallinity, and chemical composition of the Pd‐Ni/Cd/PPy/Ti electrode were characterized using scanning electron microscope (SEM), X‐ray diffraction (XRD), and X‐ray photoelectron spectroscopy (XPS), respectively. Hydrogen spillover occurred on the trimetallic catalysts, and secondary hydrogen spillover occurred on the PPy/Ti support. The enhanced hydrogen sorption capacity was due to both the synergistic effect of the trimetallic catalysts and the assistance of PPy, making Pd‐Ni/Cd/PPy/Ti a promising hydrogen storage material.

This work aimed at investigating electrocatalytic hydrodechlorination (ECH) mechanisms of chlorophenols (CPs) on a Pd-modified cathode. Experiments on the ECH of 2,4-dichlorophenol were conducted under extreme test conditions, i.e., with various buffer solutions and several sodium salt solutions as supporting electrolytes. Buffer solutions promote dechlorination due to their property of retarding the alkalinity of a solution. ECH was found to be significantly inhibited by sulfite. Experimental results showed that sulfite poisoning on Pd catalysts was reversible. Protonation may account, at least in part, for the observed high pH dependency of ECH, which proceeded rapidly, with lower apparent activation energy ( E a ) in the acidic electrolyte. In addition, pH influenced the selectivity of dechlorination of CPs. It was inferred that the ECH of CPs on the Pd-modified electrode was a preactivated electrocatalytic reaction.

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Phosphorus (P) pollution and phosphorus recovery are important issues in the field of environmental science. In this work, a novel Al-Ti bimetal composite sorbent was developed via a cost-effective co-precipitation approach for P removal from water. The adsorptive performance and characteristics of P onto Al-Ti sorbent were evaluated by batch adsorption experiments. The effects of Al:Ti molar ratio, initial P concentration and reaction temperature were investigated. The microstructural characteristics of the Al-Ti sorbent were confirmed by scanning electron microscopy (SEM), X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, and nitrogen adsorption-desorption measurements. Kinetic studies showed that the adsorption of P on Al-Ti oxide proceeds according to pseudo-second-order kinetics. The maximum adsorption capacity of phosphate on the Al-Ti oxide calculated from linear Langmuir models was 68.2 mg-P/g at pH 6.8. The Al-Ti oxide composite sorbent showed good potential for P recovery, owing to its large adsorption capacity and ease of regeneration.