铅(Pb)金属的积累会对周围环境造成严重威胁,并对肝脏和肾脏造成损害。在过去的几年里,微生物诱导碳酸盐沉淀(microbial-induced carbonate precipitation,简称MICP)技术由于其较好的可操作性已被广泛应用于污染场地复原再利用。然而,...铅(Pb)金属的积累会对周围环境造成严重威胁,并对肝脏和肾脏造成损害。在过去的几年里,微生物诱导碳酸盐沉淀(microbial-induced carbonate precipitation,简称MICP)技术由于其较好的可操作性已被广泛应用于污染场地复原再利用。然而,极端环境(比如强酸条件)会导致碳酸盐沉淀的降解,增加Pb^(2+)迁移扩散和二次环境污染风险。将基于微胶囊技术的自愈碳酸盐沉淀材料应用于含铅废水修复,其研究结果表明,在孢子萌发阶段微胶囊不仅防止了孢子受到恶劣pH条件的威胁,而且为孢子的生长和繁殖提供了肌苷和酵母提取物等营养来源,还为它们的附着提供了额外的位点,进而实现了细菌孢子与Pb^(2+)的成核,最终达到90%以上的修复效率。从扫描电子显微镜(scanning electron microscope,简称SEM)、扫描电子显微镜与能谱仪(scanning electron microscope with energy dispersive X-ray spectroscopy,简称SEM-EDS)和X射线衍射(X-ray diffraction,简称XRD)等细观测试中识别了白铅矿和方解石矿物,而在傅里叶变换红外光谱(Fourier transform infrared spectrum,简称FTIR)测试中证实胞外聚合物(extracellular polymeric substance,简称EPS)的存在,这些细观测试结果证实了细菌孢子和矿化产物共同参与了Pb^(2+)的修复。展开更多
Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studi...Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studied. The numerical simulation results show that 0.15–0.06 mm fine magnetite powder can decrease the disturbances caused by the bubbles. This is beneficial to the uniformity of the gas-solid interactions and thus to the uniformity and stability of the bed density and height. The experimental results show that, with an increase in the fine coal content in medium solids, both the fluidization quality and the beneficiation performance of the bed decreased gradually. When the fine coal content was no more than 13%, a relatively high superficial gas velocity increased the beneficiation efficiency. When the content was more than 13%, part of the fine coal was separated, leading to product layers. The separation efficiency was therefore gradually decreased. The models for predicting the bed density standard deviation and the probable error, E, value were both proposed. The E value can reach to 0.04–0.07 g/cm^3 under the optimized experimental parameters. This work provides a foundation for the adjustment of the bed density and the separation performance of the modularized 40–60 ton per hour dry coalbeneficiation industrial system.展开更多
Self-made TiO2 nanoparticles were used as photoelectrode material of dye sensitized solar cell. The TiO2 thin film coats through spreading nanoparticles evenly onto the ITO glass via self-made spin-heat platform, and ...Self-made TiO2 nanoparticles were used as photoelectrode material of dye sensitized solar cell. The TiO2 thin film coats through spreading nanoparticles evenly onto the ITO glass via self-made spin-heat platform, and then TiO2 thin film is soaked in the dye N-719 more than 12 h to prepare the photoelectrode device. The TiO2 nanoparticles produced by electric-discharge-nanofluid-process have premium anatase crystal property, and its diameter can be controlled within a range of 20-50 nm. The surface energy zeta potential of nanofluid is from -22 mV to -28.8 mV, it is a stable particle suspension in the deionized water. A trace of surfactant Triton X-100 put upon the surface of ITO glass can produce a uniform and dense TiO2 thin film and heating up the spin platform to 200 oC is able to eliminate mixed surfac-tant. Self-made TiO2 film presents excellent dye absorption performance and even doesn＇t need heat treatment procedure to enhance essential property. Results of energy analysis show the thicker film structure will increase the short-circuit current density that causes higher conversion efficiency. But, as the film structure is large and thick, both the open-circuit voltage and fill factor will decline gradually to lead bad efficiency of dye-sensitized solar cell.展开更多
The rapid development of perovskite solar cells(PSCs) has stimulated great interest in the fabrication of colorful PSCs to meet the needs of aesthetic purposes in varied applications including building integrated phot...The rapid development of perovskite solar cells(PSCs) has stimulated great interest in the fabrication of colorful PSCs to meet the needs of aesthetic purposes in varied applications including building integrated photovoltaics and wearable electronics. However, it remains challenging to prepare high-efficiency PSCs with attractive colors using perovskites with broad optical absorption and large absorption coefficients. Here we show that high-efficiency PSCs exhibiting distinct structural colors can be readily fabricated by employing Ti O2 nanobowl(NB) arrays as a nanostructured electron transport layer to integrate with a thin overlayer of perovskite on the NB arrays. A new crystalline precursor film based on lead acetate was prepared through a Lewis acid-base adduct approach, which allowed for the formation of a uniform overlayer of high-quality CH3 NH3 Pb I3 crystals on the inner walls of the NBs. The PSCs fabricated using the Ti O2 NB arrays showed angle-dependent vivid colors under light illumination. The resultant colorful PSCs exhibited a remarkable photovoltaic performance with a champion efficiency up to16.94% and an average efficiency of 15.47%, which are recordbreaking among the reported colorful PSCs.展开更多
Organic-inorganic hybrid perovskites are ideal materials for photodetection owing to their high charge carrier mobility, long charge carrier diffusion length, low dark current density and sharp absorption edge. Howeve...Organic-inorganic hybrid perovskites are ideal materials for photodetection owing to their high charge carrier mobility, long charge carrier diffusion length, low dark current density and sharp absorption edge. However, a relatively small band gap(1.6 e V) limits their photonharvesting efficiency in the near-infrared region. In the present work, we demonstrate a hybrid methylamine iodide and Pb-Sn binary perovskite as the light absorption layer in photodetectors. Experimentally, the wavelength of photoresponse onset for the photodetectors can be extended to as great as 1,000 nm when the Sn content of the hybrid perovskite is increased to 30 mol%. In addition, the photodetectors exhibit a photoresponsivity of 0.39 A W^-1, a specific detectivity of 7×10^12 Jones, a fast photoresponse with rise and decay time constants and an external quantum efficiency greater than 50% in the wavelength range of350–900 nm, with a maximum value of about 80% at 550 nm.展开更多
The quality of the perovskite light absorption layer plays a dynamic role in the photovoltaic properties of solar cells.The existing methods to prepare methylammonium lead iodide(MAPbI3)films render substantial struct...The quality of the perovskite light absorption layer plays a dynamic role in the photovoltaic properties of solar cells.The existing methods to prepare methylammonium lead iodide(MAPbI3)films render substantial structural defect density,particularly at the grain boundaries and film surface,constituting a challenge that hinders the further optoelectronic enhancement of perovskite solar cells.Herein,a unique approach was introduced:using a simple ethylammonium chloride(EACl)additive in perovskite precursor mixture to produce high-quality MAPbI3 thin films.The results indicated that EACl could encourage perovskite crystal growth without experiencing the intermediate phase formation and would evaporate from the perovskite after annealing.Additionally,a gradient perovskite structure was achieved using this technique,which impressively enhanced the performance of the perovskite films.A high power conversion efficiency(PCE)of 20.03%was achieved under the optimal amount of EACl,and the resultant efficient device could retain over 89%of the original PCE after aging for 1000 h at room temperature.This novel technique leads to a facile fabrication of highquality and less-defect perovskite thin films for competent and stable devices.展开更多
2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency ...2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency perovskite solar cells(PSCs). In general, it is prepared by a halogen solvent(chlorobenzene, CBZ) and needs an ion dopant(lithium bis(trifluoromethanesulfonyl)imide, Li-TFSI) to improve its conductivity and hole mobility. However, such a halogen solvent is not environmentally friendly and the widely used LiTFSI dopant would affect the stability of PSCs. Herein, we develop a non-halogen solvent-tetrahydrofuran(THF)-prepared spiro-OMeTAD solution with a new p-type dopant,potassium bis(fluorosulfonyl)imide(K-FSI), to apply into PSCs. By this strategy, high-hole-mobility spiro-OMeTAD film is achieved. Meanwhile, the potassium ions introduced by diffusion into perovskite surface passivate the interfacial defects. Therefore, a hysteresis-free champion PSC with an efficiency of 21.02% is obtained, along with significantly improved stability against illumination and ambient conditions. This work provides a new strategy for HTMs toward hysteresis-free high-efficiency and stable PSCs by substituting dopants.展开更多
文摘铅(Pb)金属的积累会对周围环境造成严重威胁,并对肝脏和肾脏造成损害。在过去的几年里,微生物诱导碳酸盐沉淀(microbial-induced carbonate precipitation,简称MICP)技术由于其较好的可操作性已被广泛应用于污染场地复原再利用。然而,极端环境(比如强酸条件)会导致碳酸盐沉淀的降解,增加Pb^(2+)迁移扩散和二次环境污染风险。将基于微胶囊技术的自愈碳酸盐沉淀材料应用于含铅废水修复,其研究结果表明,在孢子萌发阶段微胶囊不仅防止了孢子受到恶劣pH条件的威胁,而且为孢子的生长和繁殖提供了肌苷和酵母提取物等营养来源,还为它们的附着提供了额外的位点,进而实现了细菌孢子与Pb^(2+)的成核,最终达到90%以上的修复效率。从扫描电子显微镜(scanning electron microscope,简称SEM)、扫描电子显微镜与能谱仪(scanning electron microscope with energy dispersive X-ray spectroscopy,简称SEM-EDS)和X射线衍射(X-ray diffraction,简称XRD)等细观测试中识别了白铅矿和方解石矿物,而在傅里叶变换红外光谱(Fourier transform infrared spectrum,简称FTIR)测试中证实胞外聚合物(extracellular polymeric substance,简称EPS)的存在,这些细观测试结果证实了细菌孢子和矿化产物共同参与了Pb^(2+)的修复。
基金financially supported by the National Program on Key Basic Research Project of China (No.2012CB214904)the National Natural Science Foundation of China (Nos.51221462,51134022 and 51174203)
文摘Wide-size-range medium-solids are used in a modularized coal beneficiation demonstration system with a gas-solid fluidized bed. The characteristics of fluidization and dry-beneficiation of the medium solids were studied. The numerical simulation results show that 0.15–0.06 mm fine magnetite powder can decrease the disturbances caused by the bubbles. This is beneficial to the uniformity of the gas-solid interactions and thus to the uniformity and stability of the bed density and height. The experimental results show that, with an increase in the fine coal content in medium solids, both the fluidization quality and the beneficiation performance of the bed decreased gradually. When the fine coal content was no more than 13%, a relatively high superficial gas velocity increased the beneficiation efficiency. When the content was more than 13%, part of the fine coal was separated, leading to product layers. The separation efficiency was therefore gradually decreased. The models for predicting the bed density standard deviation and the probable error, E, value were both proposed. The E value can reach to 0.04–0.07 g/cm^3 under the optimized experimental parameters. This work provides a foundation for the adjustment of the bed density and the separation performance of the modularized 40–60 ton per hour dry coalbeneficiation industrial system.
文摘Self-made TiO2 nanoparticles were used as photoelectrode material of dye sensitized solar cell. The TiO2 thin film coats through spreading nanoparticles evenly onto the ITO glass via self-made spin-heat platform, and then TiO2 thin film is soaked in the dye N-719 more than 12 h to prepare the photoelectrode device. The TiO2 nanoparticles produced by electric-discharge-nanofluid-process have premium anatase crystal property, and its diameter can be controlled within a range of 20-50 nm. The surface energy zeta potential of nanofluid is from -22 mV to -28.8 mV, it is a stable particle suspension in the deionized water. A trace of surfactant Triton X-100 put upon the surface of ITO glass can produce a uniform and dense TiO2 thin film and heating up the spin platform to 200 oC is able to eliminate mixed surfac-tant. Self-made TiO2 film presents excellent dye absorption performance and even doesn＇t need heat treatment procedure to enhance essential property. Results of energy analysis show the thicker film structure will increase the short-circuit current density that causes higher conversion efficiency. But, as the film structure is large and thick, both the open-circuit voltage and fill factor will decline gradually to lead bad efficiency of dye-sensitized solar cell.
基金supported by the National Natural Science Foundation of China (21673007)
文摘The rapid development of perovskite solar cells(PSCs) has stimulated great interest in the fabrication of colorful PSCs to meet the needs of aesthetic purposes in varied applications including building integrated photovoltaics and wearable electronics. However, it remains challenging to prepare high-efficiency PSCs with attractive colors using perovskites with broad optical absorption and large absorption coefficients. Here we show that high-efficiency PSCs exhibiting distinct structural colors can be readily fabricated by employing Ti O2 nanobowl(NB) arrays as a nanostructured electron transport layer to integrate with a thin overlayer of perovskite on the NB arrays. A new crystalline precursor film based on lead acetate was prepared through a Lewis acid-base adduct approach, which allowed for the formation of a uniform overlayer of high-quality CH3 NH3 Pb I3 crystals on the inner walls of the NBs. The PSCs fabricated using the Ti O2 NB arrays showed angle-dependent vivid colors under light illumination. The resultant colorful PSCs exhibited a remarkable photovoltaic performance with a champion efficiency up to16.94% and an average efficiency of 15.47%, which are recordbreaking among the reported colorful PSCs.
基金the International Cooperation Foundation of China (2015DFR10700)the National Natural Science Foundation of China (51403203) for the support of this researchthe support of the Russian Ministry of Education and Science state assignment (3.3197.2017/ПЧ)
文摘Organic-inorganic hybrid perovskites are ideal materials for photodetection owing to their high charge carrier mobility, long charge carrier diffusion length, low dark current density and sharp absorption edge. However, a relatively small band gap(1.6 e V) limits their photonharvesting efficiency in the near-infrared region. In the present work, we demonstrate a hybrid methylamine iodide and Pb-Sn binary perovskite as the light absorption layer in photodetectors. Experimentally, the wavelength of photoresponse onset for the photodetectors can be extended to as great as 1,000 nm when the Sn content of the hybrid perovskite is increased to 30 mol%. In addition, the photodetectors exhibit a photoresponsivity of 0.39 A W^-1, a specific detectivity of 7×10^12 Jones, a fast photoresponse with rise and decay time constants and an external quantum efficiency greater than 50% in the wavelength range of350–900 nm, with a maximum value of about 80% at 550 nm.
基金supported by the National Key R&D Program of China(2019YFB1503202)the 111 Project(B16016)+1 种基金the National Natural Science Foundation of China(51702096,U1705256 and 61904053)the Fundamental Research Funds for the Central Universities(2019MS026,2019MS027 and 2020MS080)。
文摘The quality of the perovskite light absorption layer plays a dynamic role in the photovoltaic properties of solar cells.The existing methods to prepare methylammonium lead iodide(MAPbI3)films render substantial structural defect density,particularly at the grain boundaries and film surface,constituting a challenge that hinders the further optoelectronic enhancement of perovskite solar cells.Herein,a unique approach was introduced:using a simple ethylammonium chloride(EACl)additive in perovskite precursor mixture to produce high-quality MAPbI3 thin films.The results indicated that EACl could encourage perovskite crystal growth without experiencing the intermediate phase formation and would evaporate from the perovskite after annealing.Additionally,a gradient perovskite structure was achieved using this technique,which impressively enhanced the performance of the perovskite films.A high power conversion efficiency(PCE)of 20.03%was achieved under the optimal amount of EACl,and the resultant efficient device could retain over 89%of the original PCE after aging for 1000 h at room temperature.This novel technique leads to a facile fabrication of highquality and less-defect perovskite thin films for competent and stable devices.
基金financially supported by the National Key Research and Development Plan (2019YFE0107200 and 2017YFE0131900)the National Natural Science Foundation of China (21875178 and 91963209)Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory (XHD2020-001 and XHT2020-005)。
文摘2,2’,7,7’-tetrakis-(N,N-di-4-methoxyphenylamino)-9,9’-spirobifluorene(spiro-OMeTAD), as the most commonly used hole transport material(HTM), plays a significant role in the normal structured(n-i-p) high-efficiency perovskite solar cells(PSCs). In general, it is prepared by a halogen solvent(chlorobenzene, CBZ) and needs an ion dopant(lithium bis(trifluoromethanesulfonyl)imide, Li-TFSI) to improve its conductivity and hole mobility. However, such a halogen solvent is not environmentally friendly and the widely used LiTFSI dopant would affect the stability of PSCs. Herein, we develop a non-halogen solvent-tetrahydrofuran(THF)-prepared spiro-OMeTAD solution with a new p-type dopant,potassium bis(fluorosulfonyl)imide(K-FSI), to apply into PSCs. By this strategy, high-hole-mobility spiro-OMeTAD film is achieved. Meanwhile, the potassium ions introduced by diffusion into perovskite surface passivate the interfacial defects. Therefore, a hysteresis-free champion PSC with an efficiency of 21.02% is obtained, along with significantly improved stability against illumination and ambient conditions. This work provides a new strategy for HTMs toward hysteresis-free high-efficiency and stable PSCs by substituting dopants.
