草甘膦是一种广谱除草剂, 2015年世界卫生组织国际癌症研究机构宣布草甘膦可能对人类致癌(2A类).单斜白钨矿型BiVO_4是一种较广泛研究的可见光光催化剂,但由于其光生电子和空穴迁移慢且容易复合而导致其光催化活性低.此外,有研究表明, B...草甘膦是一种广谱除草剂, 2015年世界卫生组织国际癌症研究机构宣布草甘膦可能对人类致癌(2A类).单斜白钨矿型BiVO_4是一种较广泛研究的可见光光催化剂,但由于其光生电子和空穴迁移慢且容易复合而导致其光催化活性低.此外,有研究表明, BiVO_4的(040)晶面易于光生载流子分离,从而提高其光催化性能.Bi_2S_3的带隙能为1.27 eV,能被全可见光(400-800 nm)激发.Bi_2S_3的导带和价带位置与BiVO_4匹配,能形成异质结,从而提高其光催化活性.本文以EDTA为导向剂, L-半胱氨酸为硫源和软模板,采用一锅水热法制备了单斜白钨矿型BiVO_4,主要以(040)晶面为暴露面的Bi_2S_3/BiVO_4复合光催化剂.采用钼锑抗分光光度法测定草甘膦最终光催化降解产物之一PO_4^(3-)浓度,来计算草甘膦的降解率.X射线衍射(XRD)结果表明, Bi_2S_3/BiVO_4复合光催化剂只含Bi_2S_3和BiVO_4两种成分,没有其他晶相存在.场发射扫描电子显微镜(FESEM)显示,纯BiVO_4为片状结构,随着Bi_2S_3复合量增加, Bi_2S_3/BiVO_4的形貌为小片组成的牡丹状;但Bi_2S_3复合量进一步增加, Bi_2S_3/BiVO_4颗粒聚集严重.XRD, FESEM和高分辨透射电子显微镜(HRTEM)结果表明, Bi_2S_3复合量对Bi_2S_3/BiVO4样品(040)和(121)面晶生长及形貌有显著影响.Bi_2S_3的复合提高了Bi_2S_3/BiVO_4对可见光的吸收能力,经计算BiVO_4和Bi_2S_3带隙能分别为2.42和1.27 eV.随着Bi_2S_3复合量增加, Bi_2S_3/BiVO_4的光催化活性逐渐提高,至1 mmol时最高,对草甘膦的降解率为纯BiVO_4的2.2倍;但随着Bi2S3复合量进一步增加, Bi_2S_3/BiVO_4的光催化活性反而下降,可能是由于Bi_2S_3量太多包覆在BiVO_4表面而Bi_2S_3光催化性能很差的缘故.瞬态光电流测试和电化学阻抗谱的结果证实, Bi_2S_3/BiVO_4比BiVO_4具有更有效的电荷分离和更快的界面电荷转移能力.活性成分捕获剂实验表明,加入空穴捕获剂EDTA或电子捕获剂K_2Cr_2O_7完全抑制了草甘膦的降解.ESR谱证明羟基自由基·OH的存在.通过计算,得出BiVO_4的价带电位(EVB=2.87 eV vs. NHE)比Bi_2S_3 (EVB=1.69 eV vs. NHE)正,而Bi_2S_3 (EVB=0.42 eV vs. NHE)的导带电位比BiVO_4 (EVB=0.45 eV vs. NHE)负,能带匹配,即光生电子从Bi2S3迁移至Bi VO4,光生空穴从BiVO_4迁移至Bi_2S_3,从而将光生电子与空穴有效分离利用,达到提高其光催化性能的目的.Bi_2S_3/BiVO_4样品对草甘膦的光催化降解活性提高,主要是由于Bi_2S_3/BiVO_4异质结结构的形成提高了其对可见光的吸收能力和电子空穴对的分离效率.此外, Bi_2S_3/BiVO_4具有相对稳定性和可重复使用性.该方法简单,可制备用于光催化降解有机污染、光催化裂解水和光催化还原二氧化碳等不同领域的高活性复合光催化剂.展开更多
In recent years,the excessive use of antibiotics has become a serious problem for human health.BiV04 regarded as one of the most promising visible-light-driven photocatalysts was used to degrade the antibiotics.In thi...In recent years,the excessive use of antibiotics has become a serious problem for human health.BiV04 regarded as one of the most promising visible-light-driven photocatalysts was used to degrade the antibiotics.In this paper,we fabricated Bi/BiV04 plasmonic photocatalysts which enhanced the photocatalytic activity of BiV04 for degradation of tetracycline(TC)antibiotic.The Bi/BiV04 photocatalysts were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,transmission electron microscopy and high-resolution transmission electron microscopy.In addition,the photocatalytic experiment results show that the 0.04-Bi/BiVO4 sample has the best photocatalytic activity for 2 times than the pure BiV04 photocatalyst.The cycle experiments,after four repetitions of the experiments,showed the sample still maintained a high photocatalytic activity.Finally,the photocatalytic reaction mechanism was also studied by free radical capture experiments and electron paramagnetic resonance spectroscopy.展开更多
Streptomycin(STR)plays an essential role in bacterial infection treatments.Selectivity and sensitivity of photoelectrochemical(PEC)sensors are the two most important parameters,which can be measured using the photosen...Streptomycin(STR)plays an essential role in bacterial infection treatments.Selectivity and sensitivity of photoelectrochemical(PEC)sensors are the two most important parameters,which can be measured using the photosensitivity of its active material.We prepared a novel PEC sensor to detect STR using Bi/BiVO4/LDH(layered double hydroxides)heterostructures as an active material,which is photoactive in the visible light wavelength range.The simultaneous presence of LDH and Bi/BiVO4 enhanced the material photocurrent response,which was linear to the STR concentrations in the 0.01–500 nmol/L range.The STR detection limit by this sensor was 0.0042 nmol/L.Our novel PEC-based sensing strategy includes using an ultra-sensitive and highly selective sensor for STR detection.Additionally,the two-pot synthesis of Bi/BiVO4/LDH developed in this work is environmentally friendly.展开更多
基金supported by the National Natural Science Foundation of China(21407059,61308095)Science Development Project of Jilin Province,China(20130522071JH,20130102004JC,20140101160JC)~~
文摘草甘膦是一种广谱除草剂, 2015年世界卫生组织国际癌症研究机构宣布草甘膦可能对人类致癌(2A类).单斜白钨矿型BiVO_4是一种较广泛研究的可见光光催化剂,但由于其光生电子和空穴迁移慢且容易复合而导致其光催化活性低.此外,有研究表明, BiVO_4的(040)晶面易于光生载流子分离,从而提高其光催化性能.Bi_2S_3的带隙能为1.27 eV,能被全可见光(400-800 nm)激发.Bi_2S_3的导带和价带位置与BiVO_4匹配,能形成异质结,从而提高其光催化活性.本文以EDTA为导向剂, L-半胱氨酸为硫源和软模板,采用一锅水热法制备了单斜白钨矿型BiVO_4,主要以(040)晶面为暴露面的Bi_2S_3/BiVO_4复合光催化剂.采用钼锑抗分光光度法测定草甘膦最终光催化降解产物之一PO_4^(3-)浓度,来计算草甘膦的降解率.X射线衍射(XRD)结果表明, Bi_2S_3/BiVO_4复合光催化剂只含Bi_2S_3和BiVO_4两种成分,没有其他晶相存在.场发射扫描电子显微镜(FESEM)显示,纯BiVO_4为片状结构,随着Bi_2S_3复合量增加, Bi_2S_3/BiVO_4的形貌为小片组成的牡丹状;但Bi_2S_3复合量进一步增加, Bi_2S_3/BiVO_4颗粒聚集严重.XRD, FESEM和高分辨透射电子显微镜(HRTEM)结果表明, Bi_2S_3复合量对Bi_2S_3/BiVO4样品(040)和(121)面晶生长及形貌有显著影响.Bi_2S_3的复合提高了Bi_2S_3/BiVO_4对可见光的吸收能力,经计算BiVO_4和Bi_2S_3带隙能分别为2.42和1.27 eV.随着Bi_2S_3复合量增加, Bi_2S_3/BiVO_4的光催化活性逐渐提高,至1 mmol时最高,对草甘膦的降解率为纯BiVO_4的2.2倍;但随着Bi2S3复合量进一步增加, Bi_2S_3/BiVO_4的光催化活性反而下降,可能是由于Bi_2S_3量太多包覆在BiVO_4表面而Bi_2S_3光催化性能很差的缘故.瞬态光电流测试和电化学阻抗谱的结果证实, Bi_2S_3/BiVO_4比BiVO_4具有更有效的电荷分离和更快的界面电荷转移能力.活性成分捕获剂实验表明,加入空穴捕获剂EDTA或电子捕获剂K_2Cr_2O_7完全抑制了草甘膦的降解.ESR谱证明羟基自由基·OH的存在.通过计算,得出BiVO_4的价带电位(EVB=2.87 eV vs. NHE)比Bi_2S_3 (EVB=1.69 eV vs. NHE)正,而Bi_2S_3 (EVB=0.42 eV vs. NHE)的导带电位比BiVO_4 (EVB=0.45 eV vs. NHE)负,能带匹配,即光生电子从Bi2S3迁移至Bi VO4,光生空穴从BiVO_4迁移至Bi_2S_3,从而将光生电子与空穴有效分离利用,达到提高其光催化性能的目的.Bi_2S_3/BiVO_4样品对草甘膦的光催化降解活性提高,主要是由于Bi_2S_3/BiVO_4异质结结构的形成提高了其对可见光的吸收能力和电子空穴对的分离效率.此外, Bi_2S_3/BiVO_4具有相对稳定性和可重复使用性.该方法简单,可制备用于光催化降解有机污染、光催化裂解水和光催化还原二氧化碳等不同领域的高活性复合光催化剂.
基金Supported by the National Natural Science Foundation of China(21522603,21503142,21671083)Six Talent Peaks Project in Jiangsu Province(XCL-025)+1 种基金the China Postdoctoral Science Foundation(2017M611720)the Excellent Youth Foundation of Jiangsu Scientific Committee(BK20170526).
文摘In recent years,the excessive use of antibiotics has become a serious problem for human health.BiV04 regarded as one of the most promising visible-light-driven photocatalysts was used to degrade the antibiotics.In this paper,we fabricated Bi/BiV04 plasmonic photocatalysts which enhanced the photocatalytic activity of BiV04 for degradation of tetracycline(TC)antibiotic.The Bi/BiV04 photocatalysts were characterized by X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,transmission electron microscopy and high-resolution transmission electron microscopy.In addition,the photocatalytic experiment results show that the 0.04-Bi/BiVO4 sample has the best photocatalytic activity for 2 times than the pure BiV04 photocatalyst.The cycle experiments,after four repetitions of the experiments,showed the sample still maintained a high photocatalytic activity.Finally,the photocatalytic reaction mechanism was also studied by free radical capture experiments and electron paramagnetic resonance spectroscopy.
基金supported by Key projects of science and technology research in Hebei Higher Education Institutions(Nos.ZD2018311,ZD2020417)Local science and technology development fund projects guided by the Central Government(No.206Z1402G)+1 种基金Science and Technology Research Project of Colleges and Universities in Hebei Province(No.BJ2019203)Xingtai Science and Technology Program(Nos.2018ZC031,2018ZC227,2019ZZ023,2019ZX07).
文摘Streptomycin(STR)plays an essential role in bacterial infection treatments.Selectivity and sensitivity of photoelectrochemical(PEC)sensors are the two most important parameters,which can be measured using the photosensitivity of its active material.We prepared a novel PEC sensor to detect STR using Bi/BiVO4/LDH(layered double hydroxides)heterostructures as an active material,which is photoactive in the visible light wavelength range.The simultaneous presence of LDH and Bi/BiVO4 enhanced the material photocurrent response,which was linear to the STR concentrations in the 0.01–500 nmol/L range.The STR detection limit by this sensor was 0.0042 nmol/L.Our novel PEC-based sensing strategy includes using an ultra-sensitive and highly selective sensor for STR detection.Additionally,the two-pot synthesis of Bi/BiVO4/LDH developed in this work is environmentally friendly.
