Most electronics such as sensors,actuators and energy harvesters need piezoceramic films to interconvert mechanical and electrical energy.Transferring the ceramic films from their growth substrates for assembling elec...Most electronics such as sensors,actuators and energy harvesters need piezoceramic films to interconvert mechanical and electrical energy.Transferring the ceramic films from their growth substrates for assembling electronic devices commonly requires chemical or physical etching,which comes at the sacrifice of the substrate materials,film cracks,and environmental contamination.Here,we introduce a van der Waals stripping method to fabricate large-area and freestanding piezoceramic thin films in a simple,green,and cost-effective manner.The introduction of the quasi van der Waals epitaxial platinum layer enables the capillary force of water to drive the separation process of the film and substrate interface.The fabricated lead-free film,Ba_(0.85)Ca_(0.15)Zr_(0.1)Ti_(0.9)O_(3)(BCZT),shows a high piezoelectric coefficient d_(33)=209±10 pm V−1 and outstanding flexibility of maximum strain 2%.The freestanding feature enables a wide application scenario,including micro energy harvesting,and covid-19 spike protein detection.We further conduct a life cycle analysis and quantify the low energy consumption and low pollution of the water-based stripping film method.展开更多
Capillary‐enabled water energy harvesters(WEHs)are capable of generating directcurrent electricity continuously.However,active‐metal electrodes can introduce metal–air batteries in these WEHs.Given the nearly ident...Capillary‐enabled water energy harvesters(WEHs)are capable of generating directcurrent electricity continuously.However,active‐metal electrodes can introduce metal–air batteries in these WEHs.Given the nearly identical device structures and output characteristics of these two technologies,it is essential to distinguish between them.Herein,we present a systematic study of the water‐activated metal–air battery(WMB)through theoretical analyses and experimental verifications.We conclude the general formation rules of the WMB from a material and device‐structure perspective.Furthermore,we provide a comparative summary of various WEHs and WMBs for easy identification.We aim to improve the comprehension of metal–air batteries in the field of WEHs and assist in distinguishing between these technologies.展开更多
基金supported by General Research Grant(Project No.11212021,No.11210822)Early Career Scheme(Project No.CityU 21210619)from the Research Grants Council of the Hong Kong Special Administrative Regionthe Innovation and Technology Fund(ITS/065/20,GHP/096/19SZ)from the Innovation and Technology Commission of the Hong Kong Special Administrative Region.
文摘Most electronics such as sensors,actuators and energy harvesters need piezoceramic films to interconvert mechanical and electrical energy.Transferring the ceramic films from their growth substrates for assembling electronic devices commonly requires chemical or physical etching,which comes at the sacrifice of the substrate materials,film cracks,and environmental contamination.Here,we introduce a van der Waals stripping method to fabricate large-area and freestanding piezoceramic thin films in a simple,green,and cost-effective manner.The introduction of the quasi van der Waals epitaxial platinum layer enables the capillary force of water to drive the separation process of the film and substrate interface.The fabricated lead-free film,Ba_(0.85)Ca_(0.15)Zr_(0.1)Ti_(0.9)O_(3)(BCZT),shows a high piezoelectric coefficient d_(33)=209±10 pm V−1 and outstanding flexibility of maximum strain 2%.The freestanding feature enables a wide application scenario,including micro energy harvesting,and covid-19 spike protein detection.We further conduct a life cycle analysis and quantify the low energy consumption and low pollution of the water-based stripping film method.
基金Research Grants Council of Hong Kong,Grant/Award Numbers:11212021,11210822。
文摘Capillary‐enabled water energy harvesters(WEHs)are capable of generating directcurrent electricity continuously.However,active‐metal electrodes can introduce metal–air batteries in these WEHs.Given the nearly identical device structures and output characteristics of these two technologies,it is essential to distinguish between them.Herein,we present a systematic study of the water‐activated metal–air battery(WMB)through theoretical analyses and experimental verifications.We conclude the general formation rules of the WMB from a material and device‐structure perspective.Furthermore,we provide a comparative summary of various WEHs and WMBs for easy identification.We aim to improve the comprehension of metal–air batteries in the field of WEHs and assist in distinguishing between these technologies.
