Applying molecular oxygen for organic pollutant degradation: Strategies, mechanisms, and perspectives

Molecular oxygen(O_(2))is an environmentally friendly,cost-effective,and non-toxic oxidant.Activation of O_(2) generates various highly oxidative reactive oxygen species(ROS),which efficiently degrade pollutants with minimal environmental impact.Despite extensive research on the application of O_(2) activation in environmental remediation,a comprehensive review addressing this topic is currently lacking.This review provides an informative overview of recent advancements in O_(2) activation,focusing on three primary strategies:photocatalytic activation,chemical activation,and electrochemical activation of O_(2).We elucidate the respective mechanisms of these activation methods and discuss their advantages and disadvantages.Additionally,we thoroughly analyze the influence of oxygen supply,reactive temperature,and pH on the O_(2) activation process.From electron transfer and energy transfer perspectives,we explore the pathways for ROS generation during O_(2) activation.Finally,we address the challenges faced by researchers in this field and discuss future prospects for utilizing O_(2) activation in pollution control applications.This detailed analysis enhances our understanding and provides valuable insights for the practical implementation of organic pollutant degradation.

One-step synthesis of three-dimensional mesoporous Co_(3)O_(4)@Al_(2)O_(3)nanocomposites with deep eutectic solvent:An efficient and stable peroxymonosulfate activator for organic pollutant degradations

The effective,stable,and secure catalysts are essential for sulfate radical(SO_(4)·−)-based advanced oxidation processes(SR-AOPs)to the degradation of organic contaminants in water.Heterogeneous supported cobalt-based catalysts are commonly used to activate peroxymonosulfate(PMS)to achieve the degradation.In this work,we synthesized Co_(3)O_(4)@Al_(2)O_(3)three-dimensional(3D)mesoporous nanocomposite(denoted as Co_(3)O_(4)@Al_(2)O_(33)DPNC)in just one step by calcining cheap and green deep eutectic solvent(DES)solution containing Co salt.Co_(3)O_(4)@Al_(2)O_(33)DPNC with the high specific surface area(93.246 m^(2)/g),uniform pore distribution(3.829 nm)and rich porosity(0.255 cm^(3)/g)were attained in a beautiful hierarchical structure which exhibited the open 3D propeller-like microstructure,two-dimensional lamellar substructure with rich folds,as well as the decoration of highly dispersed Co_(3)O_(4)nanoparticles on mesoporous amorphous Al_(2)O_(3).The excellent chemical and thermal stability of Al_(2)O_(3)ensures the high stability of the catalyst,and the formation of the complex hierarchical structure makes the active Co_(3)O_(4)be homogenously dispersed for effective catalysis.The catalyst demonstrated outstanding performance for catalytic degradations of organic pollutants(acetaminophen,oxytetracycline,5-sulfosalicylic acid,orange G and Rhodamine B)by generated SO_(4)·−,·OH and^(1)O_(2).With a very low cobalt content(equal to 28.2 mg/L of Co),the catalyst exhibited very high stability and excellent reusability in the recycling usages,while the leaching of the cobalt element(<0.145 mg/L)was also at a low level.Our catalyst achieved effective degradations of acetaminophen in cycles without losing its stable hierarchical nanostructure.

Design of metal-organic frameworks(MOFs)-based photocatalyst for solar fuel production and photo-degradation of pollutants

Metal organic frameworks(MOFs)is a research hotspot in the solar fuel production and photo-degradation of pollutants field due to high surface area,rich metal/organic species,large pore volume,and adjustability of structures and compositions.Therefore,in this review,we first summarized the design factors of photocatalytic materials based on MOF from the perspective of"star"MOF.The modification strategies of MOFs-based photocatalysts were discussed to improve its photocatalytic activity and specific applications were summarized as well,including photocatalytic CO_(2)reduction,photocatalytic water splitting and photo-degradation of pollutants.Finally,the advantages and disadvantages of MOFs-based photocatalysts were discussed,the current challenges were highlighted,and suggestions for future research directions were proposed.

Heterojunction between anodic TiO_2/g-C_3N_4 and cathodic WO_3/W nano-catalysts for coupled pollutant removal in a self-biased system

An anodic TiO2/g-C3N4 hetero-junction and cathodic WO3/W were used to build a self-sustained catalytic fuel cell system for oxidizing rhodamine B or triclosan and reducing NO3^--N to N2 simultaneously.The WO3 nano-catalyst was formed in situ by heating and oxidizing a tungsten wire in air.Cyclic voltammetry and current-time curves were used to characterize the electrochemical properties of the electrodes and system.Aeration and activation of molecular oxygen by self-biased TiO2/g-C3N4 led to the formation of reactive oxidizing species in the fuel cell.The mechanism of simultaneous anodic oxidation of pollutants and cathodic reduction of nitrate was proposed.The spontaneously formed circuit and tiny current were used simultaneously in treating two kinds of wastewater in the reactor chambers,even without light illumination or an external applied voltage.This new catalytic pollution control route can lower energy consumption and degrade many other kinds of pollutants.

One-step preparation of Fe_xO_y/N-GN/CNTs heterojunctions as a peroxymonosulfate activator for relatively highly-efficient methylene blue degradation

Persulfate decontamination technologies utilizing radical‐driven processes are powerful tools for the treatment of a broad range of impurities.However,the design of high‐performance catalytic activators with multi‐functionality remains a great challenge.Therefore,in this study,three‐dimensional multifunctional FexOy/N‐GN/CNTs(N‐GN:nitrogen‐doped graphene,CNTs:carbon nanotubes)heterojunctions,which can be employed as microwave absorbers and catalysts,were synthesized via a solvothermal method and applied to activate peroxymonosulfate for the degradation of methylene blue(MB).X‐ray diffraction(XRD),Fourier transform infrared spectrometer(FTIR),scanning electron microscope(SEM),and X‐ray photoelectron microscopy(XPS)analyses revealed that the FexOy were anchored in‐situ onto the N‐GN network.Using MB as the model organic dye,various factors,such as degradation systems,PMS loading,initial organic pollutant concentration,and catalyst dosage were optimized.The results revealed that the remarkable efficiency was attributable to the synergistic effects of carbon,nitrogen,and iron‐based species.The oxidation system corresponded to the pseudo‐first‐order kinetic with a k value of^0.33 min^-1.It was demonstrated that both SO4^-and OH^-were the predominant reactive species through quenching experiments.Because these heterojunctions were employed as microwave absorbers and have a semiconductor‐like texture,the Fe/N co‐rich hierarchical porous carbon skeleton favored electron transport and storage.These heterojunctions increase the options for transitional metal catalysts and highlights the importance of designing other heterojunctions for specific applications,such as supercapacitors,energy storage,CO2 capture,and oxygen reduction electrocatalysts.

Hetero-Janus Nanofibers as an Ideal Framework for Promoting Water-pollutant Photoreforming Hydrogen Evolution

Photoreforming hydrogen evolution(Pr-HE)of a water-pollutant system could simultaneously achieve efficient hydrogen production and pollutant degradation.It provides a new way to solve energy and environmental issues,but the poor internal charge separation still limits its performance.This work designed hetero-Janus nanofibers(HJNFs)with ordered electric field distribution and separated redox surfaces to promote Pr-HE of the water-pollutant system.Taking ZnO/NiO heterojunction as an example,the hetero-Janus structures were prepared via"Dual-channel"electrospinning and further confirmed by the element morphology analysis and asymmetric distribution of the XPS spectra.The theoretical simulation showed that Janus structures could effectively inhibit the electron trap and hole trap generation,then accelerate the directional carrier migration to the surface.Experimental investigations also confirmed that Janus structures could effectively suppress internal exciton luminescence and accelerate surface charge transfer.The Pr-HE amount and the corresponding propranolol(PRO)degradation rate of HJNFs were 7.9 and 1.5 times higher than hetero-mixed nanofibers(HMNFs).The enhancement factor of Pr-HE in water-PRO to pure water was about 3.1,but nearly zero for HMNFs.This prominent synergistic effect was due to the enhancement of charge separation and the inhibition of cascade side reaction from hetero-Janus structures.Furthermore,the synchronous Pr-HE and degradation reactions were significantly promoted by selective introducing Ag nanoparticles in one side of the HJNFs for enlarging the interfacial Fermi energy level difference.The hetero-Janus strategy offers a new perspective on designing efficient photoreforming photocatalysts for energy and environment applications.

The Degradation and Pollution of Soils on the Territory of the Kovykta Gas Condensate Field

In this paper, research results from the time interval 2002-2012 are used to give an account of the chemical composition of soils on the territory of the Kovykta gas condensate field. The findings presented provide a better understanding of the ecological state of soil cover, its resilience to anthropogenic impacts, and its possible disturbance caused by the drilling pad construction activity, and by the laying of geophysical profiles. An analysis of soil pollution for the study territory generally showed that the soils are polluted with chemical elements which refer to toxicity classes： Pb, Cu, Ni, Cr, Ba and Mn. High levels ofoil products were detected near boreholes. Strong mineralization was recorded in the soil near borehole. It has a chloride-sodium chemical composition. As a result of the construction of foundation pits, recesses, ditches and earth embankments, the soil is totally destroyed, and rock outcrops show up. Disturbances of the sod cover due to road construction or even by all-terrain vehicles in these extreme conditions entail an accelerated development of linear erosion to form scours and gullies. Elimination of the canopy layer leads to an increase in surface heating, and to an acceleration of permafrost thawing. Swamping is accelerated on negative relief forms due to the increased entry of melt waters.

Terpyridine-based metallo-cuboctahedron nanomaterials for efficient photocatalytic degradation of persistent organic pollutants

Metal–organic cage photocatalysts with nanoscale dimensions have received wide attention in the field of photocatalytic environmental pollutant treatment due to their large cavities,easy modification,high tunability,and enriched active sites.Herein,we prepared a series of dihydroanthracene-cored terpyridine-based metallo-cuboctahedron nanomaterials through a selfassembly method,which exhibited satisfactory degradation performance for persistent organic pollutants under visible light irradiation.In particular,under light conditions,S1-Zn,one of the prepared nanomaterials,produced photogenerated holes oxidizing water molecules to∙OH,which attacked ibuprofen(IBU)for up to 95% degradation.Simultaneously,the corresponding photogenerated electrons reduced the dissolved oxygen in water,producing 66.2μmol/L hydrogen peroxide.The obtained supramolecular photocatalytic materials have a stable structure with non-precious metals and do not require a sacrificial agent.The metal sites of metallo-cuboctahedrons adsorb pollutants and transfer captured holes to them,accelerating degradation and promoting simultaneous H_(2)O_(2) production.This work not only proposes a simple and efficient synthesis method for supramolecular photocatalysts but also opens up opportunities for efficient,low-cost,and multifunctional materials for environmental persistent organic pollutants treatment.

A Z-scheme LaFeO_(3)-CuFe_(2)O4 composite for sulfate radical-based photocatalytic process:Synergistic effect and mechanism

The sulfate radical-based photocatalytic process is supposed to be the most promising way to degrade organic pollutants.However,the development of a suitable and efficient photocatalyst is very challenging.The 40LaFeO_(3)-CuFe_(2)O_(4)(40LFO-CFO)nanocomposite was constructed and its catalytic performance was studied using Rhodamine B(RhB)as the target pollutant.40LFO-CFO exhibited excellent RhB degradation by the persulfate(PS)-assisted photocatalytic process compared to the pristine LFO and CFO.The degradation rate constant for RhB by 40LFO-CFO in the Vis/PS system was 2.22h^(-1)which is 3.04 times and 5.05 times higher than the pristine LFO(0.73 h^(-1))and CFO(0.44h^(-1)),respectively.Furthermore,the trapping experiments and EPR spectra proved that h^(+) plays a leading role in the bleaching of RhB for the 40LFO-CFO/PS/Vis system.The enhanced photocatalytic oxidation activity of 40LFO-CFO could be attributed to the unique charge carriers flow in 40LFO-CFO due to the Z-scheme and the cooperation effect between photocatalysis and PS activation.The recycle tests confessed the stability of 40LFO-CFO.Additionally,the intermediates and products of RhB are detected by liquid chromatographymass spectrometry(LC-MS),and the photocatalytic degradation routes of RhB for the 40LFO-CFO/Vis/PS system were proposed.Moreover,the 40LFO-CFO nanocomposite has a superior catalytic performance for other organics,suggesting that it is a promising heterocatalyst because of its high catalytic activity and stability for the PS-assisted photocatalytic process.

MoS_(2)as a cocatalyst applied in advanced oxidation processes for enhancing degradation of organic pollutants:a review

Fenton technology,as a typical advanced oxidation processes(AOPs),can generate reactive oxygen species(ROS)of strong oxidation capacity to degrade organic pollutants,which has attracted wide attention.However,it is accompanied by the slow Fe^(3+)/Fe^(2+)cycle rate,easy to generate iron sludge and so on.Recently,it has been proven that the inorganic cocatalysts represented by MoS_(2)can effectively solve the above problems.Meanwhile,MoS_(2)can accelerate the activation of peroxy mono sulfate(PMS)and peroxodisulfate(PDS)by Fe^(2+).In this paper,MoS_(2)as the cocatalyst in H_(2)O_(2)+Fe^(2+),PMS+Fe^(2+)and PDS+Fe_(2+)were comprehensively reviewed.Specially,the cycling processes of Fe^(3+)/Fe^(2+)in different systems,the cocatalytic effect of MoS_(2)by the exposed active sites,the ROS generation mechanism as well as the microscopic mechanism during the reaction were elaborated emphatically.The results indicate that the reductive active sites on the surface of MoS_(2)can promote the regeneration of Fe^(2+)through the cycle between Fe^(3+)/Fe^(2+)and Mo^(4+)/Mo^(5+)/Mo^(6+).Thus,ROS such as·OH,SO_4^(·-)and ^(1)O_(2)with strong oxidizing property can be produced to improve the degradation efficiency of organic pollutants.At last,the challenges and developments of MoS_(2)cocatalysts in AOPs for practical applications were prospected.This review contributes to a deeper understanding of the cocatalytic effect of two-dimensional metal sulfides in AOPs and facilitates their industrial application.

Bicarbonate activation of hydrogen peroxide: A new emerging technology for wastewater treatment

The serious limitations of available technologies for decontamination of wastewater have compelled researchers to search for alternative solutions. Catalytic treatment with hydrogen peroxide, which appears to be one of the most efficient treatment systems, is able to degrade various organics with the help of powerful ·OH radicals. This review focuses on recent progress in the use of bicarbonate activated hydrogen peroxide for wastewater treatment. The introduction of bicarbonate to pollutant treatment has led to appreciable improvements, not only in process efficiency, but also in process stability. This review describes in detail the applications of this process in homogeneous and heterogeneous systems. The enhanced degradation, limited or lack of leaching during heterogeneous degradation, and prolonged catalysts stability during degradation are salient features of this system. This review provides readers with new knowledge regarding bicarbonate, including the fact that it does not always harm pollutant degradation, and can significantly benefit degradation under some conditions.

Interfacial engineering of graphitic carbon nitride(g-C_3N_4)-based metal sulfide heterojunction photocatalysts for energy conversion: A review

As one of the most appealing and attractive technologies, photocatalysis is widely used as a promising method to circumvent the environmental and energy problems. Due to its chemical stability and unique physicochemical, graphitic carbon nitride (g-C3N4) has become research hotspots in the community. However, g-C3N4 photocatalyst still suffers from many problems, resulting in unsatisfactory photocatalytic activity such as low specific surface area, high charge recombination and insufficient visible light utilization. Since 2009, g-C3N4-based heterostructures have attracted the attention of scientists worldwide for their greatly enhanced photocatalytic performance. Overall, this review summarizes the recent advances of g-C3N4-based nanocomposites modified with transition metal sulfide (TMS), including (1) preparation of pristine g-C3N4,(2) modification strategies of g-C3N4,(3) design principles of TMS-modified g-C3N4 heterostructured photocatalysts, and (4) applications in energy conversion. What is more, the characteristics and transfer mechanisms of each classification of the metal sulfide heterojunction system will be critically reviewed, spanning from the following categories:(1) Type I heterojunction,(2) Type II heterojunction,(3) p-n heterojunction,(4) Schottky junction and (5) Z-scheme heterojunction. Apart from that, the application of g-C3N4-based heterostructured photocatalysts in H2 evolution, CO2 reduction, N2 fixation and pollutant degradation will also be systematically presented. Last but not least, this review will conclude with invigorating perspectives, limitations and prospects for further advancing g-C3N4-based heterostructured photocatalysts toward practical benefits for a sustainable future.

A review on TiO_2-based Z-scheme photocatalysts

TiO2‐based Z‐scheme photocatalysts have attracted considerable attention because of the low recombination rate of their photogenerated electron–hole pairs and their high photocatalytic efficiency.In this review,the reaction mechanism of Z‐scheme photocatalysts,recent research progress in the application of TiO2‐based Z‐scheme photocatalysts,and improved methods for photocatalytic performance enhancement are explored.Their applications,including water splitting,CO2reduction,decomposition of volatile organic compounds,and degradation of organic pollutants,are also described.The main factors affecting the photocatalytic performance of TiO2‐based Z‐scheme photocatalysts,such as pH,conductive medium,cocatalyst,architecture,and mass ratio,are discussed.Concluding remarks are presented,and some suggestions for the future development of TiO2‐based Z‐scheme photocatalysts are highlighted.

Two-Dimensional Transition Metal Oxide and Chalcogenide-Based Photocatalysts

Two-dimensional(2D) transition metal oxide and chalcogenide(TMO&C)-based photocatalysts have recently attracted significant attention for addressing the current worldwide challenges of energy shortage and environmental pollution. The ultrahigh surface area and unconventional physiochemical, electronic and optical properties of 2D TMO&Cs have been demonstrated to facilitate photocatalytic applications. This review provides a concise overview of properties, synthesis methods and applications of 2D TMO&C-based photocatalysts. Particular attention is paid on the emerging strategies to improve the abilities of light harvesting and photoinduced charge separation for enhancing photocatalytic performances,which include elemental doping, surface functionalization as well as heterojunctions with semiconducting and conductive materials. The future opportunities regarding the research pathways of 2D TMO&C-based photocatalysts are also presented.

Hydrogen producing water treatment through mesoporous TiO2 nanofibers with oriented nanocrystals

The development of well-defined TiO2 nanoarchitectures is a versatile strategy to achieve high-efficiency photocatalytic performance.In this study,mesoporous TiO2 nanofibers consisting of oriented nanocrystals were fabricated by a facile vapothermal-assisted topochemical transformation of preformed H-titanate nanobelts.The vapothermal temperature is crucial in tuning the microstructures and photocatalytic redox properties of the resulting mesoporous TiO2 nanofibers.The microstructures were characterized with XRD,TEM,XPS and nitrogen adsorption-desorption isotherms,etc.The photocatalytic activities were evaluated by photocatalytic oxidation of organic pollutant(Rhodamine B as an example)as well as photocatalytic reduction of water to generate hydrogen(H2).The nanofibers vapothermally treated at 150°C showed the highest photocatalytic activity in both oxidation and reduction reactions,2 times higher than that of P25.The oriented alignment and suitable mesoporosity in the resulting nanofiber architecture were crucial for enhancing photocatalytic performances.The oriented alignment of anisotropic anatase nanocrystals shall facilitate faster vectorial charge transportation along the nanofibers architecture.And,the suitable mesoporosity and high surface area would also effectively enhance the mass exchange during photocatalytic reactions.We also demonstrate that efficient energy-recovering photocatalytic water treatments could be accomplished by a cascading oxic-anoxic process where the dye is degraded in the oxic phase and hydrogen is generated in the successive anoxic phase.This study showcases a novel and facile method to fabricate mesoporous TiO2 nanofibers with high photocatalytic activity for both clean energy production and environmental purification.

SYNTHESIS OF HYDROPHILIC ZnS NANOCRYSTALS AND THEIR APPLICATION IN PHOTOCATALYTIC DEGRADATION OF DYE POLLUTANTS

Hydrophilic ZnS nanocrystals with narrow size distribution were synthesized via homogeneous precipita- tion using EDTA as stabilizer. The as-synthesized products were characterized with XRD, TEM, HRTEM and UV-Vis spectrum. UV-Vis spectra showed that ZnS nanocrystals exhibited strong quantum-confined effect with a blue shift in the band gap of light absorbance. The photocatalytic activity of these nanocrystals was also investigated for the liquid phase photocatalytic degradation of Basic Violet 5BN (BV5) dye under UV irradiation. It was found that the ZnS nanocrystals had good catalytic activity for photodegradation of BV5.

Phosphorene-Based Heterostructured Photocatalysts

Semiconductor photocatalysis is a potential pathway to solve the problems of global energy shortage and environmental pollution.Black phosphorus(BP)has been widely used in the field of photocatalysis owing to its features of high hole mobility,adjustable bandgap,and wide optical absorption range.Nevertheless,pristine BP still exhibits unsatisfactory photocatalytic activity due to the low separation efficiency of photoinduced charge carriers.In recent years,the construction of heterostructured photocatalysts based on BP has become a research hotspot in photocatalysis with the remarkable improvement of photoexcited charge-separation efficiency.Herein,progress on the design,synthesis,properties,and applications of BP and its corresponding heterostructured photocatalysts is summarized.Furthermore,the photocatalytic applications of BP-based heterostructured photocatalysts in water splitting,pollutant degradation,carbon dioxide reduction,nitrogen fixation,bacterial disinfection,and organic synthesis are reviewed.Opportunities and challenges for the exploration of advanced BP-based heterostructured photocatalysts are presented.This review will promote the development and applications of BP-based heterostructured photocatalysts in energy conversion and environmental remediation.

Recent Progress,Challenges,and Prospects in Two‑Dimensional Photo‑Catalyst Materials and Environmental Remediation

The successful photo-catalyst library gives significant information on feature that affects photo-catalytic performance and proposes new materials.Competency is considerably significant to form multi-functional photo-catalysts with flexible characteristics.Since recently,two-dimensional materials(2DMs)gained much attention from researchers,due to their unique thickness-dependent uses,mainly for photo-catalytic,outstanding chemical and physical properties.Photo-catalytic water splitting and hydrogen(H2)evolution by plentiful compounds as electron(e−)donors is estimated to participate in constructing clean method for solar H2-formation.Heterogeneous photocatalysis received much research attention caused by their applications to tackle numerous energy and environmental issues.This broad review explains progress regarding 2DMs,significance in structure,and catalytic results.We will discuss in detail current progresses of approaches for adjusting 2DMs-based photo-catalysts to assess their photo-activity including doping,hetero-structure scheme,and functional formation assembly.Suggested plans,e.g.,doping and sensitization of semiconducting 2DMs,increasing electrical conductance,improving catalytic active sites,strengthening interface coupling in semiconductors(SCs)2DMs,forming nano-structures,building multi-junction nano-composites,increasing photo-stability of SCs,and using combined results of adapted approaches,are summed up.Hence,to further improve 2DMs photo-catalyst properties,hetero-structure design-based 2DMs’photo-catalyst basic mechanism is also reviewed.

Thermal catalysis under dark ambient conditions in environmental remediation:Fundamental principles, development, and challenges

Thermal catalytic degradation of organic pollutants conducted in the dark at room temperature under atmospheric pressure without the need of external chemicals and energy sources has attracted a lot of attention over the last two decades. It provides unparalleled advantages over other advanced oxidation processes (AOPs) in treating domestic and industrial contaminated wastewater from the viewpoint of energy/chemical conservation and ease of operation. Rich knowledge has been accumulated in terms of the synthesis and application of thermal catalysts though controversies remain regarding their underlying mechanisms. This review sheds light on the proposed thermo- catalysis mechanism for the first time and presents the development of thermal catalysts under dark ambient conditions with a focus on catalyst materials, catalytic activity, and mechanism. The present review aims to provide mechanistic insights into the rational design of novel and efficient catalysts, and their underlying mechanisms as well as the emerging challenges and perspectives in thermo-catalysis under dark ambient conditions used for the practical and efficient treatment of contaminated wastewater.

BiVO_4 Photoanode with Exposed(040) Facets for Enhanced Photoelectrochemical Performance

A BiVO_4 photoanode with exposed(040) facets was prepared to enhance its photoelectrochemical performance.The exposure of the(040) crystal planes of the BiVO_4 film was induced by adding NaCl to the precursor solution. The asprepared BiVO_4 photoanode exhibits higher solar-light absorption and charge-separation efficiency compared to those of an anode prepared without adding Na Cl. To our knowledge,the photocurrent density(1.26 m A cm^(-2) at 1.23 V vs. RHE) of as-prepared BiVO_4 photoanode is the highest according to the reports for bare BiVO_4 films under simulated AM1.5 G solar light, and the incident photon-to-current conversion efficiency is above 35% at 400 nm. The photoelectrochemical(PEC)water-splitting performance was also dramatically improvedwith a hydrogen evolution rate of 9.11 lmol cm^(-2) h^(-1), which is five times compared with the BiVO_4 photoanode prepared without NaCl(1.82 lmol cm^(-2) h^(-1)). Intensity-modulated photocurrent spectroscopy and transient photocurrent measurements show a higher charge-carrier-transfer rate for this photoanode. These results demonstrate a promising approach for the development of high-performance BiVO_4 photoanodes which can be used for efficient PEC water splitting and degradation of organic pollutants.