A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV...A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV-Vis diffuse reflectance, scanning electron microscopy, and X-ray photoelectron spectroscopic characterizations. Photocatalytic experiments demonstrated that the synthesized BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst exhibited excellent photocatalytic performance toward the degradation of tetracycline hydrochloride(TCH) under simulated sunlight. Furthermore, the TCH degradation rate of BiOCl0.9I0.1/15%β-Bi2O3 increased by 27.6% and 61.4% compared with those of the pure BiOCl0.9I0.1 and pure β-Bi2O3, respectively. Due to the multiple vacancies and valence states possessed by BiOCl0.9I0.1/x%β-Bi2O3, namely Bi5+, Bi(3-x)+, Bi5+–O, Bi3+–O, I- and I3-, the charge separation in photocatalysis reactions can be effectively promoted. The Mott-Schottky measurements indicate that the conduction band(CB) level of BiOCl0.9I0.1/15%β-Bi2O3 becomes more negative relative to that of BiOCl0.9I0.1, guaranteeing an advantageous effect on the redox ability of the photocatalyst. This study provides a new bright spot for the construction of high-performance photocatalysts.展开更多
Ag2O has attracted much recent attention,because of its high photocatalytic activity in the ultraviolet(UV)‐visible region.However,there have been few reports on the near‐infrared(NIR)photocatalytic activity of Ag2O...Ag2O has attracted much recent attention,because of its high photocatalytic activity in the ultraviolet(UV)‐visible region.However,there have been few reports on the near‐infrared(NIR)photocatalytic activity of Ag2O.This paper reports the high NIR photocatalytic activity of Ag2O nanoparticles.Ag2O is unsuitable for application in full‐solar‐spectrum photocatalysis,because it is unstable under UV irradiation.A surface sulfurization process was carried out to address this issue.Specifically,a layer of Ag2S2O7nanoparticles was grown on the surface of the Ag2O nanoparticles,to improve the stability of the Ag2O photocatalyst and enhance its photocatalytic activity in the UV,visible and NIR regions.The Ag2O/Ag2S2O7heterostructure is a stable and efficient full‐solar‐spectrum photocatalyst.It has potential application in the photodegradation of organic pollutants,and more generally in environmental engineering where full utilization of the solar spectrum is required.展开更多
Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement ...Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement of 1.23 eV and kinetic energy loss of about 0.6 eV, a photo-voltage of 1.8 V produced by PEC cells is generally required for spontaneous water splitting. Therefore, the minimum bandgap of1.8 eV is demanded for photoactive materials in single-photoelectrode PEC cells, and the bandgap of about 1 eV for back photoactive materials is appropriate in tandem PEC cells. All these PEC cells cannot effectively utilize the infrared light from 1250 to 2500 nm. In order to realize the full spectrum utilization of solar light, here, we develop a solar-driven PEC water splitting system integrated with a thermoelectric device. The key feature of this system is that the thermoelectric device produces a voltage as an additional bias for the PEC system by using the temperature difference between the incident infrared-light heated aqueous electrolyte in the PEC cell as the hot source and unirradiated external water as the cold source. Compared to a reference PEC system without the thermoelectric device, this system has a significantly improved overall water splitting activity of 1.6 times and may provide a strategy for accelerating the application of full spectrum solar light-driven PEC cells for hydrogen production.展开更多
文摘A novel and effective BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst was synthesized through a precipitation method. The structure, morphology, and optical properties of the samples were certified by X-ray diffraction, UV-Vis diffuse reflectance, scanning electron microscopy, and X-ray photoelectron spectroscopic characterizations. Photocatalytic experiments demonstrated that the synthesized BiOCl0.9I0.1/x%β-Bi2O3 composite catalyst exhibited excellent photocatalytic performance toward the degradation of tetracycline hydrochloride(TCH) under simulated sunlight. Furthermore, the TCH degradation rate of BiOCl0.9I0.1/15%β-Bi2O3 increased by 27.6% and 61.4% compared with those of the pure BiOCl0.9I0.1 and pure β-Bi2O3, respectively. Due to the multiple vacancies and valence states possessed by BiOCl0.9I0.1/x%β-Bi2O3, namely Bi5+, Bi(3-x)+, Bi5+–O, Bi3+–O, I- and I3-, the charge separation in photocatalysis reactions can be effectively promoted. The Mott-Schottky measurements indicate that the conduction band(CB) level of BiOCl0.9I0.1/15%β-Bi2O3 becomes more negative relative to that of BiOCl0.9I0.1, guaranteeing an advantageous effect on the redox ability of the photocatalyst. This study provides a new bright spot for the construction of high-performance photocatalysts.
基金supported by the National Natural Science Foundation of China(51372142)the Innovation Research Group(51321091)the Program of Introducing Talents of Discipline to Universities in China(111 program,b06015)~~
文摘Ag2O has attracted much recent attention,because of its high photocatalytic activity in the ultraviolet(UV)‐visible region.However,there have been few reports on the near‐infrared(NIR)photocatalytic activity of Ag2O.This paper reports the high NIR photocatalytic activity of Ag2O nanoparticles.Ag2O is unsuitable for application in full‐solar‐spectrum photocatalysis,because it is unstable under UV irradiation.A surface sulfurization process was carried out to address this issue.Specifically,a layer of Ag2S2O7nanoparticles was grown on the surface of the Ag2O nanoparticles,to improve the stability of the Ag2O photocatalyst and enhance its photocatalytic activity in the UV,visible and NIR regions.The Ag2O/Ag2S2O7heterostructure is a stable and efficient full‐solar‐spectrum photocatalyst.It has potential application in the photodegradation of organic pollutants,and more generally in environmental engineering where full utilization of the solar spectrum is required.
基金This work was supported by the National Natural Science Foundation of China(51825204 and 51629201)the Key Research Program of Frontier Sciences CAS(QYZDB-SSW-JSC039).
文摘Common solar-driven photoelectrochemical(PEC) cells for water splitting were designed by using semiconducting photoactive materials as working photoelectrodes to capture sunlight. Due to the thermodynamic requirement of 1.23 eV and kinetic energy loss of about 0.6 eV, a photo-voltage of 1.8 V produced by PEC cells is generally required for spontaneous water splitting. Therefore, the minimum bandgap of1.8 eV is demanded for photoactive materials in single-photoelectrode PEC cells, and the bandgap of about 1 eV for back photoactive materials is appropriate in tandem PEC cells. All these PEC cells cannot effectively utilize the infrared light from 1250 to 2500 nm. In order to realize the full spectrum utilization of solar light, here, we develop a solar-driven PEC water splitting system integrated with a thermoelectric device. The key feature of this system is that the thermoelectric device produces a voltage as an additional bias for the PEC system by using the temperature difference between the incident infrared-light heated aqueous electrolyte in the PEC cell as the hot source and unirradiated external water as the cold source. Compared to a reference PEC system without the thermoelectric device, this system has a significantly improved overall water splitting activity of 1.6 times and may provide a strategy for accelerating the application of full spectrum solar light-driven PEC cells for hydrogen production.
