危险电子废物阴极射线管(cathode ray tube,CRT)是当前我国电子垃圾处理处置中首要必须解决的难题,其关键在于含铅锥玻璃的处理处置。本研究探讨了真空碳热还原法从CRT锥玻璃中分离并回收有害重金属铅的同时回收钾和钠的规律。结果表明...危险电子废物阴极射线管(cathode ray tube,CRT)是当前我国电子垃圾处理处置中首要必须解决的难题,其关键在于含铅锥玻璃的处理处置。本研究探讨了真空碳热还原法从CRT锥玻璃中分离并回收有害重金属铅的同时回收钾和钠的规律。结果表明,铅、钾和钠的回收率随温度的升高、压力的降低、碳加入量的增加及保持时间的延长而增大;当温度为1000℃、系统压力为10 Pa时,加入10%的碳粉并保持4 h,铅回收率接近100%,钠和钾的回收率分别为65.04%和50.55%。该方法为废弃阴极射线管玻璃的无害化和资源化提供了理论依据和实验数据。展开更多
Electrocatalytic water splitting for hydrogen production is a key approach to tackling the current energy crisis.Among the catalysts,the traditional Pd@C catalysts are remarkable for their efficiency in hydrogen evolu...Electrocatalytic water splitting for hydrogen production is a key approach to tackling the current energy crisis.Among the catalysts,the traditional Pd@C catalysts are remarkable for their efficiency in hydrogen evolution.However,the high cost and scarcity of Pd catalysts,as well as the instability caused by the corrosiveness of carbon-based substrates,hinder their large-scale application.To overcome this challenge,an effective strategy is to construct highly dispersed Pd single atoms to improve palladium utilization and choose more stable materials as supports.In this study,TiO_(2-x)carriers with abundant oxygen vacancies were prepared and loaded with Pd by photoreduction deposition.Adjusting the palladium content resulted in three forms of Pd-loaded TiO_(2-x):nanoparticles(Pd@TiO_(2-x)(6%,10%)),nanoclusters(Pd@TiO_(2-x)(3%))and single atoms(Pd@TiO_(2-x)(1.5%)).The oxygen vacancies improved the stability of the titanium dioxide materials by providing more active hydrogen adsorption sites and increasing the affinity of Pd for active hydrogen.Single atom loading increased the frequency of oxygen holes in the support and the high activity of monatomic Pd promoted the adsorption of active hydrogen and facilitated the formation of active hydrogen intermediates.The synergistic effect of single atoms and oxygen vacancies improved the stability and catalytic activity of the composite material.Pd@TiO_(2-x)(1.5%)showed outstanding performance in hydrogen evolution in an acidic medium with an overpotential of only 24 m V at a current density of 10 m A/cm^(2)and a low Tafel rise of 41.9 m V/dec.This study provides an effective strategy for the development of high-performance hydrogen evolution(HER)catalysts.展开更多
文摘危险电子废物阴极射线管(cathode ray tube,CRT)是当前我国电子垃圾处理处置中首要必须解决的难题,其关键在于含铅锥玻璃的处理处置。本研究探讨了真空碳热还原法从CRT锥玻璃中分离并回收有害重金属铅的同时回收钾和钠的规律。结果表明,铅、钾和钠的回收率随温度的升高、压力的降低、碳加入量的增加及保持时间的延长而增大;当温度为1000℃、系统压力为10 Pa时,加入10%的碳粉并保持4 h,铅回收率接近100%,钠和钾的回收率分别为65.04%和50.55%。该方法为废弃阴极射线管玻璃的无害化和资源化提供了理论依据和实验数据。
基金supported by the Key Project of Tianjin Natural Science Foundation(No.23JCZDJC00570)Special Funding of China Postdoctoral Science Foundation(No.2023T160268)+3 种基金China Postdoctoral Science Foundation(No.2023M741362)the National natural science foundation of China(Nos.22276209 and 21822608)Research Center for Eco-Environmental Science(No.RCEES-TDZ-2021-7)the support from the Youth Innovation Promotion Association of CAS(No.Y2021019)。
文摘Electrocatalytic water splitting for hydrogen production is a key approach to tackling the current energy crisis.Among the catalysts,the traditional Pd@C catalysts are remarkable for their efficiency in hydrogen evolution.However,the high cost and scarcity of Pd catalysts,as well as the instability caused by the corrosiveness of carbon-based substrates,hinder their large-scale application.To overcome this challenge,an effective strategy is to construct highly dispersed Pd single atoms to improve palladium utilization and choose more stable materials as supports.In this study,TiO_(2-x)carriers with abundant oxygen vacancies were prepared and loaded with Pd by photoreduction deposition.Adjusting the palladium content resulted in three forms of Pd-loaded TiO_(2-x):nanoparticles(Pd@TiO_(2-x)(6%,10%)),nanoclusters(Pd@TiO_(2-x)(3%))and single atoms(Pd@TiO_(2-x)(1.5%)).The oxygen vacancies improved the stability of the titanium dioxide materials by providing more active hydrogen adsorption sites and increasing the affinity of Pd for active hydrogen.Single atom loading increased the frequency of oxygen holes in the support and the high activity of monatomic Pd promoted the adsorption of active hydrogen and facilitated the formation of active hydrogen intermediates.The synergistic effect of single atoms and oxygen vacancies improved the stability and catalytic activity of the composite material.Pd@TiO_(2-x)(1.5%)showed outstanding performance in hydrogen evolution in an acidic medium with an overpotential of only 24 m V at a current density of 10 m A/cm^(2)and a low Tafel rise of 41.9 m V/dec.This study provides an effective strategy for the development of high-performance hydrogen evolution(HER)catalysts.
