The development of efficient oxygen reduction reaction(ORR)electrocatalysts that utilize seawater as an electrolyte is crucial for harnessing marine resources and advancing the application of zinc-air batteries(ZABs)....The development of efficient oxygen reduction reaction(ORR)electrocatalysts that utilize seawater as an electrolyte is crucial for harnessing marine resources and advancing the application of zinc-air batteries(ZABs).Here,Er_(2)O_(3-)Pt electrocatalysts enriched oxygen vacancies were constructed by a one-step microwave method.Theoretical calculations indicate that the unique 4f orbitals of Er,in conjunction with the Pt 5d and O 2p orbitals,allow the 4f electrons to demonstrate a degree of mobility.This behavior provides flexible electronic states and optimizes the binding strength of oxygen intermediates in the ORR.In addition,quasi in-situ characterization has proven that the addition of Er and the mediation of the oxygen vacancies have enriched the electrons at Pt,effectively reducing the adsorption of Cl-and preventing the poisoning of the active site of Pt.As a result,Er_(2)O_(3-)Pt with half-wave potentials(E_(1/2))of 0.85 and 0.67 V in alkaline seawater and pure seawater,respectively,was used as a cathodic catalyst in alkaline seawater-based ZABs to obtain a maximum power density of 184.6 mW·cm^(-2)and remarkable stability in pure seawater.展开更多
Chlorine is usually applied in the urban water treatment process to deactivate pathogens and prevent waterborne diseases.As a pre-treatment,it remains unclear whether chlorinated water can effectively alleviate membra...Chlorine is usually applied in the urban water treatment process to deactivate pathogens and prevent waterborne diseases.As a pre-treatment,it remains unclear whether chlorinated water can effectively alleviate membrane fouling during ultrafiltration(UF).In this study,tap water was investigated for its effect on biofilm formation and biofouling in a gravity-driven membrane(GDM)filtration system.For comparison,biofilm/biofouling with untreated surface(lake)water was studied in parallel.It was found that more severe membrane fouling occurred with the filtration of tap water than lake water,and larger quantities of polysaccharide and extracellular DNA(eDNA)were present in the tap-water biofilm than in the lake-water biofilm.The tap-water biofilm had a densely compact morphology.In contrast,a porous,spider-like structure was observed for the lake-water biofilm,which was assumed to be associated with the bacteria in the biofilm.This hypothesis was verified by 16S ribosomal RNA(rRNA)sequencing,which demonstrated that Xanthobacter was the dominant taxon in the tap-water biofilm.Additionally,membrane hydrophobicity/hydrophilicity played a minor role in affecting the membrane fouling properties and microbial community.This study revealed the significant role of chlorine-resistant bacteria in biofouling formation and provides a deeper understanding of membrane fouling,which can potentially aid in searching for effective ways of controlling membrane fouling.展开更多
基金the National Natural Science Foundation of China(Nos.52072197,52174283,22301156)Key R.&D.,the Natural Science Foundation of Shandong Province(No.ZR2024QB012)+1 种基金the Qingdao Natural Science Foundation(24-4-4-zrjj-16-jch)Shandong Province“Double-Hundred Talent Plan”(No.WST2020003).
文摘The development of efficient oxygen reduction reaction(ORR)electrocatalysts that utilize seawater as an electrolyte is crucial for harnessing marine resources and advancing the application of zinc-air batteries(ZABs).Here,Er_(2)O_(3-)Pt electrocatalysts enriched oxygen vacancies were constructed by a one-step microwave method.Theoretical calculations indicate that the unique 4f orbitals of Er,in conjunction with the Pt 5d and O 2p orbitals,allow the 4f electrons to demonstrate a degree of mobility.This behavior provides flexible electronic states and optimizes the binding strength of oxygen intermediates in the ORR.In addition,quasi in-situ characterization has proven that the addition of Er and the mediation of the oxygen vacancies have enriched the electrons at Pt,effectively reducing the adsorption of Cl-and preventing the poisoning of the active site of Pt.As a result,Er_(2)O_(3-)Pt with half-wave potentials(E_(1/2))of 0.85 and 0.67 V in alkaline seawater and pure seawater,respectively,was used as a cathodic catalyst in alkaline seawater-based ZABs to obtain a maximum power density of 184.6 mW·cm^(-2)and remarkable stability in pure seawater.
基金financially supported by the Key Research and Development Plan of the Ministry of Science and Technology,China(2019YFD1100104 and 2019YFC1906501)。
文摘Chlorine is usually applied in the urban water treatment process to deactivate pathogens and prevent waterborne diseases.As a pre-treatment,it remains unclear whether chlorinated water can effectively alleviate membrane fouling during ultrafiltration(UF).In this study,tap water was investigated for its effect on biofilm formation and biofouling in a gravity-driven membrane(GDM)filtration system.For comparison,biofilm/biofouling with untreated surface(lake)water was studied in parallel.It was found that more severe membrane fouling occurred with the filtration of tap water than lake water,and larger quantities of polysaccharide and extracellular DNA(eDNA)were present in the tap-water biofilm than in the lake-water biofilm.The tap-water biofilm had a densely compact morphology.In contrast,a porous,spider-like structure was observed for the lake-water biofilm,which was assumed to be associated with the bacteria in the biofilm.This hypothesis was verified by 16S ribosomal RNA(rRNA)sequencing,which demonstrated that Xanthobacter was the dominant taxon in the tap-water biofilm.Additionally,membrane hydrophobicity/hydrophilicity played a minor role in affecting the membrane fouling properties and microbial community.This study revealed the significant role of chlorine-resistant bacteria in biofouling formation and provides a deeper understanding of membrane fouling,which can potentially aid in searching for effective ways of controlling membrane fouling.
