Nanowires exhibit excellent thermoelectric performance,due to the stronger quantum confinement and phonon scattering effect compared to bulk materials.However,it is a challenge to accurately evaluate the thermoelectri...Nanowires exhibit excellent thermoelectric performance,due to the stronger quantum confinement and phonon scattering effect compared to bulk materials.However,it is a challenge to accurately evaluate the thermoelectric performance of nanowires.In this paper,the thermoelectric properties of an individual suspended Sb_(2)Se_(3) nanowire have been characterized by comprehensive T-type method,including thermal conductivity,electrical conductivity,Seebeck coefficient and figure of merit.The thermal conductivity increases from 0.57 W/(m·K)to 3.69 W/(m·K)with temperature increasing from 80 K to 320 K.The lattice vibration dominates the heat conduction process,and due to its flawless crystal structure,the thermal conductivity is not lower than the reported values of bulk Sb_(2)Se_(3).The electrical conductivity increases from 7.83 S/m to 688 S/m in the temperature range of 50 K–320 K,which is a great improvement compared with the corresponding bulk value.At 294 K,the Seebeck coefficient of the Sb_(2)Se_(3) nanowire is–1120μV/K and the corresponding figure of merit is 0.064.展开更多
Li[Ni0.6Co0.2Mn0.2]O2(NCM622)is one of the best commercialized cathodes in the battery field.However,poor cyclability at relatively high temperature hinders its multiple usages.Here,operando tests were performed to in...Li[Ni0.6Co0.2Mn0.2]O2(NCM622)is one of the best commercialized cathodes in the battery field.However,poor cyclability at relatively high temperature hinders its multiple usages.Here,operando tests were performed to investigate the phase transitions and electron/ion transfer process of lavered NCM622 at 25 and 55℃.The identified spinel structure resulting in the poor cyclability at 55℃ guides the commercialization of batteries at high temperature.展开更多
基金the National Key Research and Development Program of China(Grant No.2020YFA0715000)the National Natural Science Foundation of China(NSFC)(Grant Nos.52127816 and 52176078)。
文摘Nanowires exhibit excellent thermoelectric performance,due to the stronger quantum confinement and phonon scattering effect compared to bulk materials.However,it is a challenge to accurately evaluate the thermoelectric performance of nanowires.In this paper,the thermoelectric properties of an individual suspended Sb_(2)Se_(3) nanowire have been characterized by comprehensive T-type method,including thermal conductivity,electrical conductivity,Seebeck coefficient and figure of merit.The thermal conductivity increases from 0.57 W/(m·K)to 3.69 W/(m·K)with temperature increasing from 80 K to 320 K.The lattice vibration dominates the heat conduction process,and due to its flawless crystal structure,the thermal conductivity is not lower than the reported values of bulk Sb_(2)Se_(3).The electrical conductivity increases from 7.83 S/m to 688 S/m in the temperature range of 50 K–320 K,which is a great improvement compared with the corresponding bulk value.At 294 K,the Seebeck coefficient of the Sb_(2)Se_(3) nanowire is–1120μV/K and the corresponding figure of merit is 0.064.
基金Supported by the Project of the Foshan Xianhu Laboratory of the Advanced Energy Science and Technology Guangdong Laboratory,China(No.XH12020-003)the National Natural Science Foundation of China(No.51521001)+1 种基金the National Key Research and Development Program of China(No.2016YFA0202603)the Fundamental Rescarch Funds for the Central Universities of China(No.WUT:205201019)。
文摘Li[Ni0.6Co0.2Mn0.2]O2(NCM622)is one of the best commercialized cathodes in the battery field.However,poor cyclability at relatively high temperature hinders its multiple usages.Here,operando tests were performed to investigate the phase transitions and electron/ion transfer process of lavered NCM622 at 25 and 55℃.The identified spinel structure resulting in the poor cyclability at 55℃ guides the commercialization of batteries at high temperature.
