Zhejiang Gongshang University

Heterojunction construction effectively enhances carrier separation efficiency and photocatalytic performance in semiconductors.In this study, a series of FePMo/MIL-101(Fe) heterojunctions with varying FePMo content were synthesized for the photocatalytic removal of Cr(VI) from wastewater.The photoinduced carriers were effectively separated via the S-scheme mechanism resulting from the spontaneously formed interfacial elec. field.Tafel curves confirmed that the photoelectrochem. stability of the 2% FePMo/MIL-101(Fe) heterojunction was significantly improved, with a corrosion c.d. 100 times greater than that of MIL-101(Fe) under light, indicating superior photogenerated carrier separation and photocatalytic activity.Furthermore, the 2% FePMo/MIL-101(Fe) heterojunction exhibited strong resistance to both anionic and cationic interference, demonstrating good adaptability in real water applications.After 10 consecutive cycles, the Cr(VI) removal efficiency remained high at 89%, substantially outperforming FePMo and MIL-101(Fe), which achieved removal efficiencies of 48% and 45%, resp.Scavenger experiments demonstrated that photogenerated electrons played a dominant role in the photocatalytic reduction of Cr(VI), while superoxide radicals had a secondary contribution.This study highlights the potential of the FePMo/MIL-101(Fe) heterojunction in photocatalysis and offers insights for designing novel S-scheme heterojunction photocatalysts, enhancing the practical application of photocatalytic technol.

Heterogeneous persulfate-based advanced oxidation processes (PS-AOPs) have been regarded as one of the most promising methods in the treatment of wastewater containing antibiotic.Herein, the Co₃O₄/NiO composite with built-in elec. field is preparedThe existence of built-in elec. field can reduce the interface resistance and accelerate the charge transfer, promoting the electron transfer between the Co₃O₄/NiO composite and peroxymonosulfate (PMS).Meanwhile, built-in elec. field can induce the formation of electron-deficient and electron-rich active areas.With built-in elec. field intervention, the activation pathway of PMS over Co₃O₄ component with electron-deficient area of Co₃O₄/NiO is transformed from radical to ¹O₂, while electron-rich area makes NiO component that has no ability can activate PMS producing SO^•-₄ and OH^•.As a result, the Co₃O₄/NiO composite can effectively activate PMS to realize the rapid degradation of tetracycline.More significantly, a micro reactor equipping with Co₃O₄/NiO composite not only displays high removal efficiency of total organic carbon (TOC), but also improves the biodegradability of wastewater containing antibiotic.In short, current work not only clarifies the role of built-in elec. field in PMS activation, but also shares some valuable insights into the application of PS-AOPs in practical engineering.

The development of electrocatalysts for hydrogen evolution reaction (HER) with high catalytic activity and stability in alk. medium remains a significant challenge.Herein, a catalyst (namely Zn_0.05Ni₃S₂-P) was designed to achieve the excellent alk. HER performance owing to the boosted water dissociation and moderate H* adsorption energy.At the c.d. of 10 mA cm^-2, the overpotential of Zn_0.05Ni₃S₂-P is 143 mV.In addition, the Tafel slope and the charge transfer resistance of Zn_0.05Ni₃S₂-P are reduced, and the electrochem. active surface area (ECSA) is expanded.D. functional theory (DFT) calculations show that the appropriate proportion of Ni to Zn optimizes the H* adsorption energy of the catalyst.The introduction of P cooperates with S to activate the water dissociation, reduce the H₂O dissociation energy barrier, and accelerate the reaction kinetics.Moreover, in the process of electrolytic water splitting at 100 mA cm^-2 c.d., the voltage is stable at 2.4 V, the hydrogen production rate is maintained at 1.84 mmol h^-1, and the Faraday efficiency of hydrogen production is nearly 100 %.This work simultaneously considers the importance of water dissociation and H* adsorption energy in alk. HER, and provides a strategy for the design of highly active alk. HER catalysts.