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NiFeMo hybrid film prepared by simple one-step electrodeposition can act as cathode and anode materials in an electrolytic cell for urea electrolysis to hydrogen generation and purification of wastewater containing urea. [Display omitted] • The NiFeMo hybrid film is synthesized by a facile one-step electrodeposition method. • The NiFeMo exhibits excellent performances for HER and UOR toward urea electrolysis. • The OER activity of NiFeMo facilitates H 2 production in varying urea concentration. • Mo dopant induced charge redistribution and synergistic effect between three metals. Urea electrolysis as a promising approach to highly effective and energy-saving hydrogen production, is gaining increasing attention to cope with the global energy crisis and environmental issues. In this study, we report a NiFeMo hybrid film acting as cathode and anode materials in an electrolytic cell for urea electrolysis to hydrogen generation and purification of wastewater containing urea. The NiFeMo prepared by simple one-step electrodeposition exhibits excellent electrocatalytic performances for hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). Meanwhile, the excellent oxygen evolution reaction (OER) activity of NiFeMo can ensure the smooth progress of hydrogen production in the wastewater of varying urea concentration. The results show that Mo dopant has significant effects on HER performance of the NiFeMo. The excellent OER and UOR performance of the NiFeMo is derived from synergism of these three metals and the formation of active intermediates. This work provides a facile method to synthesize low-cost and high-performance electrocatalysts for urea electrolysis and water splitting, which may open up new opportunities for hydrogen production. [ABSTRACT FROM AUTHOR]

• Pure organic Z-scheme heterojunction of TCPP/PDINH was constructed by co-assembly. • The close contact interface was formed by intermolecular π − π and hydrogen bond interactions. • 2D PDINH aggregates as support basement improved the stability and recycling of TCPP aggregates. Supramolecular structures based on orderly aggregated metal-free porphyrins (TCPP) are visible-light-driven photocatalysts. But these photocatalysts possess disadvantages of poor activity and low recycling which limit their practical applications. To improve the activity and deficiencies of TCPP aggregates as photocatalysts, TCPP was combined with organic semiconductor perylene-3,4,9,10-tetracarboxylic diimide (PDINH) aggregates to construct pure organic heterojunctions (TCPP/PDINH) through the co-assembly method in this paper. Through several characterizations, it was concluded that a close contact interface formed through intermolecular π-π stacking and hydrogen bond interactions by the co-assembly method. The photocatalytic activity for the degradation of phenol by TCPP/PDINH was enhanced compared with that of the single aggregate, and the mechanism analysis showed that the matched energy band positions of the two aggregates and the close contact interfaces promoted the formation of a Z-scheme structure, which accelerated the charge carrier separation efficiency. In addition, the existence of two-dimensional PDINH aggregates as a support basement also improved the stability of TCPP aggregates and made them heterogeneous, which enhanced their operation and recycling. [ABSTRACT FROM AUTHOR]

• A noble-metal-free Ni 2 P/CZS/Co 3 O 4 photocatalyst via three-step hydrothermal method. • The ternary heterostructure boosts photocatalytic H 2 production. • The highest H 2 evolution rate (39.66 mmol g−1 h−1) from the optimum composition. • The mechanism for photocatalytic water splitting was proposed. Constructing heterostructure for efficient charge separation is a hopeful way for enhance photocatalytic hydrogen production. In this paper, we successfully construct the Ni 2 P/Cd 0.5 Zn 0.5 S/Co 3 O 4 (Ni 2 P/CZS/Co 3 O 4) heterostructure via three-step hydrothermal method. It is demonstrated that Ni 2 P/CZS/Co 3 O 4 shows a prominent photocatalytic H 2 generation activity of 39.66 mmol g−1 h−1, revealing about 2.42 times enhancement compared to that of the pure Cd 0.5 Zn 0.5 S (CZS) under visible light. The closely contacted CZS/Co 3 O 4 forms a type-II heterostructure to accelerate the separation of photoinduced charge. The Ni 2 P acts as electron traps to capture the photoelectrons, and provide active sites for proton reduction. Moreover, the cooperative synergy of type-II heterostructure and active sites achieves an obvious improvement for photocatalytic hydrogen production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Versatile preparation strategy of negatively charged saccharide-based polymers was proposed. • The polymers can selective adsorb cationic dyes and pharmaceuticals. • The "host-guest" inclusion, π-π interaction, and electrostatic attraction are responsible for the adsorption. • The adsorption follows the pseudo-second-order kinetic model. Pursuing special negatively charged adsorbents is critical to selectively removing cationic pollutants from effluent. Herein, we proposed a versatile preparation strategy of negatively charged saccharide-based polymers using easily available saccharides as building blocks and hexachlorocyclotriphosphazene as a linker in a facile "one-step" method. Because of the existence of numerous hydroxyl groups and phosphine nitrile units in the skeleton, these polymers show selective adsorption capacity towards cationic dyes and pharmaceuticals, but not for ionic dyes and uncharged bisphenol A. Notably, β-cyclodextrin-based polymers (β-CDPs) displayed remarkable adsorption towards methylene blue (Q m , 1563 mg g−1) and promethazine (Q m , 944 mg g−1). Systematic experiments revealed that the synergy of "host-guest" inclusion, electrostatic attraction, and π-π interaction promoted the selective and efficient adsorption of cationic pollutants. Given the efficiently selective adsorption of cationic dyes and pharmaceuticals, these negatively charged saccharide-based polymers should be candidates for the adsorption of other cationic pollutants, including heavy metal ions. This work expanded the scope of the special utilization of biomass-based adsorbents for water remediation. [ABSTRACT FROM AUTHOR]