Pb contamination in aquatic environments causes severe pollution;therefore,harmless absorbents are required.In this study,we report a novel synthesis of whitlockite(WH,Ca_(18)Mg_(2)(HPO_(4))_(2)(PO_(4))_(12)),which is...Pb contamination in aquatic environments causes severe pollution;therefore,harmless absorbents are required.In this study,we report a novel synthesis of whitlockite(WH,Ca_(18)Mg_(2)(HPO_(4))_(2)(PO_(4))_(12)),which is the second most abundant biomineral in human bone,and its application as a high-performing Pb^(2+)absorbent.Hydroxyapatite(HAP)and WH are prepared via a simple precipitation method.The Pb2+absorption performance and mechanism of the synthesized biominerals are investigated in aqueous solutions at neutral pH.The results demonstrate that WH exhibits an excellent Pb2+absorption capacity of 2339 mg g^(−1),which is 1.68 times higher than the recorded value for HAP.Furthermore,the absorbed Pb^(2+) ions are recycled into high-purity PbI_(2).This is employed as a precursor for the fabrication of perovskite solar cells(PSCs),resulting in a conversion efficiency of 19.00%comparable to that of commercial PbI2 powder(99.99%purity).Our approach provides an efficient way to remove Pb^(2+)ions from water and reuse them in the recycling of PSCs.展开更多
The purpose of this study was to enhance the content of valuable metals, such as Au, Ag, and Te, in tellurium-bearing minerals via bioleaching. The ore samples composed of invisible Au and Au paragenesis minerals(such...The purpose of this study was to enhance the content of valuable metals, such as Au, Ag, and Te, in tellurium-bearing minerals via bioleaching. The ore samples composed of invisible Au and Au paragenesis minerals(such as pyrite, chalcopyrite, sphalerite and galena) in combination with tellurium-bearing minerals(hessite, sylvanite and Tellurobismuthite) were studied. Indigenous microbes from mine drainage were isolated and identified as Acidithiobacillus ferrooxidans, which were used in bioleaching after adaption to copper. The effect of the microbial adaption on the bioleaching performance was then compared with the results produced by the non-adaptive process. The microbial adaption enhanced the Au–Ag–Te contents in biological leaching of tellurium-bearing ore minerals. This suggests that bioleaching with adapted microbes can be used both as a pretreatment and in the main recovery processes of valuable metals.展开更多
The fourth industrial revolution indispensably brings explosive data processing and storage;thus,a new computing paradigm based on artificial intelligence-enabling device structure is urgently required.Memristors have...The fourth industrial revolution indispensably brings explosive data processing and storage;thus,a new computing paradigm based on artificial intelligence-enabling device structure is urgently required.Memristors have received considerable attention in this regard because of their ability to process and store data at the same location.However,fundamental problems with abrupt switching characteristics limit their practical application.To address this problem,we utilized the concept of metaplasticity inspired by biosystems and observed gradual switching in the peptide-based memristor at high proton conductivity.An unexpectedly high slope value>1.7 in the logI–V curve at low voltage(≤400 mV)was considered the main origin,and it might arise from the modulatory response of proton ions on the threshold of Ag ion migration in the peptide film.With the obtained gradual switching property at high proton conductivity,the device showed significantly increased accuracy of image recognition(~82.5%).We believe that such a demonstration not only contributes to the practical application of neuromorphic devices but also expands the bioinspired functional synthetic platform.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korea Government(MSIT)(NRF-2018M3C1B7021994)the Technology Development Program to Solve Climate Changes(2018M1A2A2058207)+3 种基金Institute of Information&Communications Technology Planning&Evaluation(IITP)grant funded by the Korea Government(MSIT)(No.2020-0-00541,Flexible Photovoltaic Device Module with Autonomous Power Supply for Smart Farm Wireless Composite IoT Sensor)Korea Institute of Energy Technology Evaluation and Planning(KETEP)grant funded by the Korea government(MOTIE)(20203040010320)the Korea Evaluation Institute of Industrial Technology(KEIT)(20016588)funded by the Korea Governmentsupported by the Research Institute of Advanced Materials(RIAM)and National Center for Inter-university Research Facilities(NCIRF)at Seoul National University.
文摘Pb contamination in aquatic environments causes severe pollution;therefore,harmless absorbents are required.In this study,we report a novel synthesis of whitlockite(WH,Ca_(18)Mg_(2)(HPO_(4))_(2)(PO_(4))_(12)),which is the second most abundant biomineral in human bone,and its application as a high-performing Pb^(2+)absorbent.Hydroxyapatite(HAP)and WH are prepared via a simple precipitation method.The Pb2+absorption performance and mechanism of the synthesized biominerals are investigated in aqueous solutions at neutral pH.The results demonstrate that WH exhibits an excellent Pb2+absorption capacity of 2339 mg g^(−1),which is 1.68 times higher than the recorded value for HAP.Furthermore,the absorbed Pb^(2+) ions are recycled into high-purity PbI_(2).This is employed as a precursor for the fabrication of perovskite solar cells(PSCs),resulting in a conversion efficiency of 19.00%comparable to that of commercial PbI2 powder(99.99%purity).Our approach provides an efficient way to remove Pb^(2+)ions from water and reuse them in the recycling of PSCs.
文摘The purpose of this study was to enhance the content of valuable metals, such as Au, Ag, and Te, in tellurium-bearing minerals via bioleaching. The ore samples composed of invisible Au and Au paragenesis minerals(such as pyrite, chalcopyrite, sphalerite and galena) in combination with tellurium-bearing minerals(hessite, sylvanite and Tellurobismuthite) were studied. Indigenous microbes from mine drainage were isolated and identified as Acidithiobacillus ferrooxidans, which were used in bioleaching after adaption to copper. The effect of the microbial adaption on the bioleaching performance was then compared with the results produced by the non-adaptive process. The microbial adaption enhanced the Au–Ag–Te contents in biological leaching of tellurium-bearing ore minerals. This suggests that bioleaching with adapted microbes can be used both as a pretreatment and in the main recovery processes of valuable metals.
基金This work was funded by a National Research Foundation of Korea(NRF)grant from the Korean government(MSIT)(No.2020R1A2C2004864)S.D.N.acknowledges the support by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute(KHIDI),funded by the Ministry of Health&Welfare,Republic of Korea(No.HI19C1234).
文摘The fourth industrial revolution indispensably brings explosive data processing and storage;thus,a new computing paradigm based on artificial intelligence-enabling device structure is urgently required.Memristors have received considerable attention in this regard because of their ability to process and store data at the same location.However,fundamental problems with abrupt switching characteristics limit their practical application.To address this problem,we utilized the concept of metaplasticity inspired by biosystems and observed gradual switching in the peptide-based memristor at high proton conductivity.An unexpectedly high slope value>1.7 in the logI–V curve at low voltage(≤400 mV)was considered the main origin,and it might arise from the modulatory response of proton ions on the threshold of Ag ion migration in the peptide film.With the obtained gradual switching property at high proton conductivity,the device showed significantly increased accuracy of image recognition(~82.5%).We believe that such a demonstration not only contributes to the practical application of neuromorphic devices but also expands the bioinspired functional synthetic platform.