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The Fe-modulated Co x Fe 1−x P@NPC exhibits excellent electrooxidation performance. [Display omitted] • The N content of NPC is increased via WLSH as precursor to increase its catalytic site density. • Co x Fe 1−x P@NPC exhibits excellent electrooxidation performance for TCH removal. • Radical generation capacity of Co x Fe 1−x P@NPC can be modulated with Fe modulation. • The mechanism for electrooxidation activity of Co x Fe 1−x P@NPC is reasonably revealed. Developing low-cost, green, high-performing electrode materials to address environmental pollutants and the energy crisis is significant but challenging. Herein, the bimetallic iron cobalt phosphide coated in waste biomass-derived N, P co-doping carbon (Co x Fe 1−x P@NPC) is constructed. Furthermore, the active site density and the water decomposition energy barrier of surface-coated NPC are modulated by optimizing the electronic structure of Co x Fe 1−x P via doping engineering. The Fe-modulated Co x Fe 1−x P@NPC exhibits a hierarchical porous self-supporting structure and excellent physical & chemical properties with excellent electrooxidation performance, achieving over 95% removal of TCH within 60 min. The density functional theory (DFT) calculations further confirms that N carries more positive charge and P carries more negative charge in the NPC of Co x Fe 1−x P@NPC with Fe modulation, which can promote the adsorption and dissociation of water molecules. Of note, Co 0.75 Fe 025 P@NPC displays a low water dissociation energy barrier to produce ·OH and a high energy barrier to produce O 2 than its counterparts. This study offers new insight into controllable modulation of biomass carbon-based composite electrode catalytic activity for high-efficiency degradation of contaminants. [ABSTRACT FROM AUTHOR]

[Display omitted] • N doping and MoP heterostructures are achieved together through co-pyrolysis methods. • The heterostructures and doped N can synergistically optimize electronic structure. • MoP@ N -NiCoP requires low overpotentials of 43 mV and 232 mV to drive HER and OER. Transition metal phosphides (TMPs) are one of the most promising alternatives to noble metal electrocatalysts, but so far their activity and stability still fall short of expectations. Here, we prepare nitrogen-doped nickel–cobalt phosphide (N -NiCoP) and molybdenum phosphide (MoP) heterostructures engineered on nickel foam (NF) with nanosheet structure by high-temperature annealing and low-temperature phosphorylation. Notably, heteroatomic N doping and heterostructures construction are achieved together through a simple co-pyrolysis method. The distinctive composition can synergistically promote the electron transfer, lower the reaction barriers, thus improving the catalytic performance. Therefore, the modified MoP@ N -NiCoP requires low overpotentials of 43 mV and 232 mV to reach 10 mA cm−2 current density for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) accompanied by satisfactory stability in 1 M KOH. Density functional theory (DFT) calculations reveal the electron coupling and synergistic interfacial effects at the heterogeneous interface. This study provides a new strategy for heterogeneous electrocatalysts with elemental doping to promote hydrogen applications. [ABSTRACT FROM AUTHOR]

A dual-functional ionic liquid additive, 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4), is developed to tune the preferential Zn(002) crystallographic texture and simultaneously suppress the hydroxide sulfate accumulation on Zn anode by dynamically manipulating electrolyte pH-surroundings. The effective suppression of Zn dendrite growth enables a Zn symmetrical cell cycling stably to over one year. [Display omitted] Zn anodes suffer from the formation of uncontrolled dendrites aggravated by the uneven electric field and the insulating by-product accumulation in aqueous zinc-ion batteries (AZIBs). Here, an effective strategy implemented by 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO 4) additive is proposed to synergistically tune the crystallographic orientation of zinc deposition and suppress the formation of zinc hydroxide sulfate for enhancing the reversibility on Zn anode surface. As a competing cation, BMI+ is proved to preferably adsorb on Zn-electrode compared with H 2 O molecules, which shields the "tip effect" and inhibits the Zn-deposition agglomerations to inducing the horizontal growth along Zn (002) crystallographic texture. Simultaneously, the protonated BMIHSO 4 additives could remove the detrimental OH– in real-time to fundamentally eliminate the accumulation of 6Zn(OH) 2 ·ZnSO 4 ·4H 2 O and Zn 4 SO 4 (OH) 6 ·H 2 O on Zn anode surface. Consequently, Zn anode exhibits an ultra-long cycling stability of one year (8762 h) at 0.2 mA cm−2/0.2 mAh cm−2, 3600 h at 2 mA cm−2/2 mAh cm−2 with a high plating cumulative capacity of 3.6 Ah cm−2, and a high average Coulombic efficiency of 99.6 % throughout 1000 cycles. This work of regulating Zn deposition texture combined with eliminating notorious by-products could offer a desirable way for stabilizing the Zn-anode/electrolyte interface in AZIBs. [ABSTRACT FROM AUTHOR]

Peroxymonosulfate activation paths in Fenton-like reaction were successfully mediated via simply altering the doped metal atoms into g -C 3 N 5. Fe-C 3 N 5 followed a non-radical activation path displayed superior catalytic activity than Co-C 3 N 5 followed a radical path. [Display omitted] • PMS activation paths are mediated by altering doped metal atoms in g -C 3 N 5. • k value in TC degradation over Fe-C 3 N 5 is 3.14 times higher than Co-C 3 N 5. • Co-C 3 N 5 follows radical activation path, while Fe-C 3 N 5 follows non-radical one. • ROS contributions over Fe-C 3 N 5 and Co-C 3 N 5 are calculated and compared. • DFT study and experimental data support varied activation path on Fe-C 3 N 5 and Co-C 3 N 5. Peroxymonosulfate (PMS) could be activated by either radical path or non-radical path, how to rationally mediate these two routines was an important unresolved issue. This work has introduced a simple way to address this problem via metal atom doping. It was found that Fe-doped nitrogen-rich graphitic carbon nitride (Fe-C 3 N 5) exhibited high activity towards PMS activation for tetracycline degradation, and the degradation rate was 3.14 times higher than that of Co-doped nitrogen-rich graphitic carbon nitride (Co-C 3 N 5). Radical trapping experiment revealed the contributions of reactive species over two catalysts were different. Electron paramagnetic resonance analysis further uncovered the non-radical activation path played a dominated role on Fe-C 3 N 5 surface, while the radical activation path was the main routine on Co-C 3 N 5 surface. Density functional theory calculations, X-ray photoelectron spectroscopy analysis, and electrochemical experiments provided convincing evidence to support these views. This study supplied a novel method to mediate PMS activation path via changing the doped metal atom in g -C 3 N 5 skeleton, and it allowed us to better optimize the PMS activation efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] Graphite carbon nitride (g-C 3 N 4) as metal-free photocatalyst has been widely studied recently in photocatalytic water reduction, which is considered as one of the promising routes to realizing the hydrogen energy-based society in the future. The generally used preparation process based on thermal polymerization of precursors easily brought the formation of aggregated nanosheets morphology, severely limiting its photocatalytic activity. Herein, the hollow tube-like morphology with porous surface was elaborately obtained by ethylene diamine tetraacetic acid (EDTA)-involved hydrothermal treatment of melamine precursor. The hollow and porous features shortened the migration distance of photo-generated carriers, trapped the incident lights, and provided more photocatalytic reactive sites, then realizing the enhanced photocatalytic H 2 -evolution activity up to 7.1 times that of pristine g-C 3 N 4. The presence of EDTA acted as the pivotal role to control the recrystallization process of melamine and its derivative, cyanuric acid, and thus to determine the framework formation of the hollow tube-like microstructure. Moreover, complete thermal decomposition of cyanuric acid during the thermal polymerization of precursors was responsible for the hollow and porous features. This work extends the morphology regulation cognition of g-C 3 N 4 based on hydrothermal treatment of precursors, and is expected to bring deep understanding and feasible strategies to design morphology-dominated highly-efficient g-C 3 N 4 photocatalysts. [ABSTRACT FROM AUTHOR]

Abstract: Ferric-impregnated volcanic ash (FVA) which consisted mainly of different forms of iron and aluminum oxide minerals was developed for arsenate (V) removal from an aqueous medium. The adsorption experiments were conducted in both DI water samples and actual water (Lake Kasumigaura, Japan) to investigate the effects of solution mineralization degree on the As(V) removal. Kinetic and equilibrium studies conducted in actual water revealed that the mineralization of water greatly elevated the As(V) adsorption on FVA. The experiment performed in DI water indicated that the existence of multivalence metallic cations significantly enhanced the As(V) adsorption ability, whereas competing anions such as fluoride and phosphate greatly decreased the As(V) adsorption. It is suggested that FVA is a cost-effective adsorbent for As(V) removal in low-level phosphate and fluoride solution. It was important to conduct the batch experiment using the actual water to investigate the arsenic removal on adsorbents. [ABSTRACT FROM AUTHOR]