As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in pra...As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in practical applications.Here,an ultra-robust and high-performance rotational triboelectric nanogenerator(R-TENG)by bearing charge pumping is proposed.The R-TENG composes of a pumping TENG(P-TENG),an output TENG(O-TENG),a voltage-multiplying circuit(VMC),and a buffer capacitor.The P-TENG is designed with freestanding mode based on a rolling ball bearing,which can also act as the rotating mechanical energy harvester.The output low charge from the P-TENG is accumulated and pumped to the non-contact O-TENG,which can simultaneously realize ultralow mechanical wear and high output performance.The matched instantaneous power of R-TENG is increased by 32 times under 300 r/min.Furthermore,the transferring charge of R-TENG can remain 95%during 15 days(6.4×10^(6)cycles)continuous operation.This work presents a realizable method to further enhance the durability of TENG,which would facilitate the practical applications of high-performance TENG in harvesting distributed ambient micro mechanical energy.展开更多
The bamboo fiber functionalized with phthalic anhydride underwent carbonization,yielding bam-boo cellulose-derived carbon nanomaterials(C-BCN).These C-BCN were subsequently integrated into an acrylamide precursor solu...The bamboo fiber functionalized with phthalic anhydride underwent carbonization,yielding bam-boo cellulose-derived carbon nanomaterials(C-BCN).These C-BCN were subsequently integrated into an acrylamide precursor solution to synthesize an ultra-robust,fatigue-resistant conductive hydrogel(PAM-C-BCN).During in situ polymerization,the abundant active sites on the C-BCN surface facilitated covalent cross-linking with the polyacrylamide(PAM)matrix.This interfacial interaction promoted strong adhesion between the PAM chains and the carbon nanostructures,forming a densely interpenetrated network through macromolecular entanglement.The synergis-tic coupling of the rigid C-BCN framework with the flexible polymer chains conferred exceptional mechanical resilience and energy dissipation capabilities to the composite hydrogel.Compared to the PAM hydrogel,the PAM-C-BCN hydrogel exhibited an improvement in mechanical prop-erties,with a fracture strength of 363 kPa(a 2.5%increase),an elongation of approximately 2254%(a 2.0%increase),a fracture energy of 30 kJ/m^(2)(a 3.1%increase),and a toughness of 3.04 MJ/m^(3)(a 4.1%increase).Moreover,PAM-C-BCN hydrogel demonstrated high adhesion(up to 7.5 kPa on pigskin)and conductivity(0.21 S/m).This strategy required neither complex design nor processing,offering a simple and efficient approach with great potential for hydrogel appli-cations requiring high mechanical performance.At the crack tip of PAM-C-BCN hydrogel,C-BCN exhibited superior crack propagation resistance compared to SiO2 nanoparticles.Importantly,this strategy offered valuable insights for developing tough and stretchable hydrogels.展开更多
Triboelectric nanogenerators （TENGs） for harvesting rotary mechanical energy are mostly based on in-plane sliding or free-standing mode. However, the relative displacement between two contacting triboelectric layers...Triboelectric nanogenerators （TENGs） for harvesting rotary mechanical energy are mostly based on in-plane sliding or free-standing mode. However, the relative displacement between two contacting triboelectric layers causes abrasion, which lowers the output power and reduces service life. Therefore, it is important to develop a method to minimize abrasion when harvesting rotary mechanical energy. Here, we report a scale-like structured TENG （SL-TENG）, in which two triboelectric layers work under a contact-separation mode to avoid in-plane relative sliding in order to minimize abrasion. As a result, the SL-TENG exhibits outstanding robustness. For example, the output voltage of the SL-TENG does not exhibit any measurable decay although this output has been continuously generated through more than a million cycles. Moreover, at a very low rotation rate of 120 rpm, the SL-TENG can generate a maximum short-drcuit current of 78 μA, delivering an instantaneous power density of 2.54 W/m^2 to an external load. In relation to this, a Li-ion battery was charged using the SL-TENG. After a 30-rain charging time, the battery achieved a discharge capacity of 0.1 mAh. Through a power management circuit integrated into the SL-TENG, a continuous direct current （DC） of 5 V is outputted, providing sufficient DC power for driving a radio-frequency wireless sensor and other conventional electronics.展开更多
The development of stretchable electronics could enhance novel interface structures to solve the stretchability-conductivity dilemma,which remains a major challenge.Herein,we report a nano-liquid metal(LM)-based highl...The development of stretchable electronics could enhance novel interface structures to solve the stretchability-conductivity dilemma,which remains a major challenge.Herein,we report a nano-liquid metal(LM)-based highly robust stretchable electrode(NHSE)with a self-adaptable interface that mimics water-tonet interaction.Based on the in situ assembly of electrospun elastic nanofiber scaffolds and electrosprayed LM nanoparticles,the NHSE exhibits an extremely low sheet resistance of 52 mΩsq^(-1).It is not only insensitive to a large degree of mechanical stretching(i.e.,350%electrical resistance change upon 570%elongation)but also immune to cyclic deformation(i.e.,5%electrical resistance increases after 330000 stretching cycles with 100%elongation).These key properties are far superior to those of the state-of-the-art reports.Its robustness and stability are verified under diverse circumstances,including long-term exposure to air(420 days),cyclic submersion(30000 times),and resilience against mechanical damages.The combination of conductivity,stretchability,and durability makes the NHSE a promising conductor/electrode solution for flexible/stretchable electronics for applications such as wearable on-body physiological signal detection,human-machine interaction,and heating e-skin.展开更多
相对位置感知作为协同导航的核心也是车辆智能驾驶的关键技术,在车辆自组网(Vehicular Ad Hoc Networks,VANET)协同定位算法中具有重要作用。然而限于系统非线性及有色噪声干扰,相同硬件平台下的相对位置后验信息获取通常局限于一定精...相对位置感知作为协同导航的核心也是车辆智能驾驶的关键技术,在车辆自组网(Vehicular Ad Hoc Networks,VANET)协同定位算法中具有重要作用。然而限于系统非线性及有色噪声干扰,相同硬件平台下的相对位置后验信息获取通常局限于一定精度。针对上述问题,基于抗差理论提出一种Huber M估计的鲁棒容积滤波(Robust Cubature Kalman Filtering,RCKF)车辆相对位置估计算法。该算法通过结合容积法则进行非线性更新,将量测方程转换为观测量和状态预测的线性回归问题后利用M估计实现求解,通过Huber损失函数降低受干扰量测值权重实现估计性能调整。紧组合车辆相对位置估计的实验表明,与容积滤波(Cubature Kalman Filter,CKF)相比,RCKF估计结果在均方根上改善23.59%,在准确度上改善21.81%,在精度上改善27.39%,有效提高了相对位置估计精确性和鲁棒性,为车辆协同定位解决方案提供一种可供参考的系统质量控制策略。展开更多
Tribovoltaic nanogenerators(TVNGs)have the characteristics of high current density,low matched impedance and continuous output,which is expected to solve the problem of power supply for small electronic devices.Howeve...Tribovoltaic nanogenerators(TVNGs)have the characteristics of high current density,low matched impedance and continuous output,which is expected to solve the problem of power supply for small electronic devices.However,wear occurrence in friction interface will seriously reduce the performance of TVNGs as well as lifetime.Here,we employ MXene solution as lubricate to improve output current density and lifetime of TVNG simultaneously,where a high value of 754 mA m^(-2)accompanied with a record durability of 90,000 cycles were achieved.By comparing multiple liquid lubricates with different polarity,we show that conductive polar liquid with MXene as additive plays a crucial role in enhancing the electrical output performance and durability of TVNG.Moreover,the universality of MXene solution is well demonstrated in various TVNGs with Cu and P-type Si,and Cu and N-GaAs as material pairs.This work may guide and accelerates the practical application of TVNG in future.展开更多
针对现有超宽带穿墙雷达时域波束成像分辨率低、旁瓣高以及干扰抑制能力弱等问题,提出利用稳健Capon波束形成对目标成像的方法。该方法基于目标回波模型首先补偿近场扩散损耗、墙体传播损耗和折射效应,实现天线阵列接收数据的配准,利用...针对现有超宽带穿墙雷达时域波束成像分辨率低、旁瓣高以及干扰抑制能力弱等问题,提出利用稳健Capon波束形成对目标成像的方法。该方法基于目标回波模型首先补偿近场扩散损耗、墙体传播损耗和折射效应,实现天线阵列接收数据的配准,利用稳健Capon波束成像得到良好的成像分辨率和更好的干扰抑制能力。利用时域有限差分(finite-difference time domain,FDTD)数值仿真和实验数据实现了隐藏目标的二维成像,验证了该方法的有效性。展开更多
基金supported by the National Natural Science Foundation of China(Nos.51922023,61874011)Fundamental Research Funds for the Central Universities(E1EG6804)
文摘As an emerging technology to convert environmental high-entropy energy into electrical energy,triboelectric nanogenerator(TENG)has great demands for further enhancing the service lifetime and output performance in practical applications.Here,an ultra-robust and high-performance rotational triboelectric nanogenerator(R-TENG)by bearing charge pumping is proposed.The R-TENG composes of a pumping TENG(P-TENG),an output TENG(O-TENG),a voltage-multiplying circuit(VMC),and a buffer capacitor.The P-TENG is designed with freestanding mode based on a rolling ball bearing,which can also act as the rotating mechanical energy harvester.The output low charge from the P-TENG is accumulated and pumped to the non-contact O-TENG,which can simultaneously realize ultralow mechanical wear and high output performance.The matched instantaneous power of R-TENG is increased by 32 times under 300 r/min.Furthermore,the transferring charge of R-TENG can remain 95%during 15 days(6.4×10^(6)cycles)continuous operation.This work presents a realizable method to further enhance the durability of TENG,which would facilitate the practical applications of high-performance TENG in harvesting distributed ambient micro mechanical energy.
基金supported by Applied Basic Research Program of Yunnan Province(No.202301AS070041)National Natural Science Foundation of China(No.32171884)+5 种基金the Major Science and Technology Project of Yunnan Province(202402AE090027)Long Yang acknowledges Candidates of the Young and Middle-Aged Academic Leaders of Yunnan Province(No.202105AC160048)the Ten Thousand Talent Program for Young Topnotch Talents of Yunnan Province(No.YNWR-QNBJ-2020-136)Guanben Du acknowledges the Yunnan Provincial Academician Workstation(No.YSZJGZZ-2020052)the 111 Project(No.D21027)supported by the Scientific Research Fund project of Education Department of Yunnan Province(No.2025J0626).
文摘The bamboo fiber functionalized with phthalic anhydride underwent carbonization,yielding bam-boo cellulose-derived carbon nanomaterials(C-BCN).These C-BCN were subsequently integrated into an acrylamide precursor solution to synthesize an ultra-robust,fatigue-resistant conductive hydrogel(PAM-C-BCN).During in situ polymerization,the abundant active sites on the C-BCN surface facilitated covalent cross-linking with the polyacrylamide(PAM)matrix.This interfacial interaction promoted strong adhesion between the PAM chains and the carbon nanostructures,forming a densely interpenetrated network through macromolecular entanglement.The synergis-tic coupling of the rigid C-BCN framework with the flexible polymer chains conferred exceptional mechanical resilience and energy dissipation capabilities to the composite hydrogel.Compared to the PAM hydrogel,the PAM-C-BCN hydrogel exhibited an improvement in mechanical prop-erties,with a fracture strength of 363 kPa(a 2.5%increase),an elongation of approximately 2254%(a 2.0%increase),a fracture energy of 30 kJ/m^(2)(a 3.1%increase),and a toughness of 3.04 MJ/m^(3)(a 4.1%increase).Moreover,PAM-C-BCN hydrogel demonstrated high adhesion(up to 7.5 kPa on pigskin)and conductivity(0.21 S/m).This strategy required neither complex design nor processing,offering a simple and efficient approach with great potential for hydrogel appli-cations requiring high mechanical performance.At the crack tip of PAM-C-BCN hydrogel,C-BCN exhibited superior crack propagation resistance compared to SiO2 nanoparticles.Importantly,this strategy offered valuable insights for developing tough and stretchable hydrogels.
基金This work is supported by the National Key R＆D Project from the Minister of Science and Technology, China （Nos. 2016YFA0202702, 2016YFA0202703, and 2016YFA0202704） and the National Natural Science Foundation of China （Nos. 21703010, 21274006 and 51503005）, the Programs for Beijing Science and Technology Leading Talent （No. Z16111000490000）.
文摘Triboelectric nanogenerators （TENGs） for harvesting rotary mechanical energy are mostly based on in-plane sliding or free-standing mode. However, the relative displacement between two contacting triboelectric layers causes abrasion, which lowers the output power and reduces service life. Therefore, it is important to develop a method to minimize abrasion when harvesting rotary mechanical energy. Here, we report a scale-like structured TENG （SL-TENG）, in which two triboelectric layers work under a contact-separation mode to avoid in-plane relative sliding in order to minimize abrasion. As a result, the SL-TENG exhibits outstanding robustness. For example, the output voltage of the SL-TENG does not exhibit any measurable decay although this output has been continuously generated through more than a million cycles. Moreover, at a very low rotation rate of 120 rpm, the SL-TENG can generate a maximum short-drcuit current of 78 μA, delivering an instantaneous power density of 2.54 W/m^2 to an external load. In relation to this, a Li-ion battery was charged using the SL-TENG. After a 30-rain charging time, the battery achieved a discharge capacity of 0.1 mAh. Through a power management circuit integrated into the SL-TENG, a continuous direct current （DC） of 5 V is outputted, providing sufficient DC power for driving a radio-frequency wireless sensor and other conventional electronics.
文摘The development of stretchable electronics could enhance novel interface structures to solve the stretchability-conductivity dilemma,which remains a major challenge.Herein,we report a nano-liquid metal(LM)-based highly robust stretchable electrode(NHSE)with a self-adaptable interface that mimics water-tonet interaction.Based on the in situ assembly of electrospun elastic nanofiber scaffolds and electrosprayed LM nanoparticles,the NHSE exhibits an extremely low sheet resistance of 52 mΩsq^(-1).It is not only insensitive to a large degree of mechanical stretching(i.e.,350%electrical resistance change upon 570%elongation)but also immune to cyclic deformation(i.e.,5%electrical resistance increases after 330000 stretching cycles with 100%elongation).These key properties are far superior to those of the state-of-the-art reports.Its robustness and stability are verified under diverse circumstances,including long-term exposure to air(420 days),cyclic submersion(30000 times),and resilience against mechanical damages.The combination of conductivity,stretchability,and durability makes the NHSE a promising conductor/electrode solution for flexible/stretchable electronics for applications such as wearable on-body physiological signal detection,human-machine interaction,and heating e-skin.
文摘相对位置感知作为协同导航的核心也是车辆智能驾驶的关键技术,在车辆自组网(Vehicular Ad Hoc Networks,VANET)协同定位算法中具有重要作用。然而限于系统非线性及有色噪声干扰,相同硬件平台下的相对位置后验信息获取通常局限于一定精度。针对上述问题,基于抗差理论提出一种Huber M估计的鲁棒容积滤波(Robust Cubature Kalman Filtering,RCKF)车辆相对位置估计算法。该算法通过结合容积法则进行非线性更新,将量测方程转换为观测量和状态预测的线性回归问题后利用M估计实现求解,通过Huber损失函数降低受干扰量测值权重实现估计性能调整。紧组合车辆相对位置估计的实验表明,与容积滤波(Cubature Kalman Filter,CKF)相比,RCKF估计结果在均方根上改善23.59%,在准确度上改善21.81%,在精度上改善27.39%,有效提高了相对位置估计精确性和鲁棒性,为车辆协同定位解决方案提供一种可供参考的系统质量控制策略。
基金Research was supported by the National Key R&D Project from Minister of Science and Technology(2021YFA1201602)National Natural Science Foundation of China(Grant no.61774016,22109013,62204017)+1 种基金Fundamental Research Funds for the Central Universities(E1E46802)China Postdoctoral Science Foundation(2021M703172,2021M703171).
文摘Tribovoltaic nanogenerators(TVNGs)have the characteristics of high current density,low matched impedance and continuous output,which is expected to solve the problem of power supply for small electronic devices.However,wear occurrence in friction interface will seriously reduce the performance of TVNGs as well as lifetime.Here,we employ MXene solution as lubricate to improve output current density and lifetime of TVNG simultaneously,where a high value of 754 mA m^(-2)accompanied with a record durability of 90,000 cycles were achieved.By comparing multiple liquid lubricates with different polarity,we show that conductive polar liquid with MXene as additive plays a crucial role in enhancing the electrical output performance and durability of TVNG.Moreover,the universality of MXene solution is well demonstrated in various TVNGs with Cu and P-type Si,and Cu and N-GaAs as material pairs.This work may guide and accelerates the practical application of TVNG in future.
文摘针对现有超宽带穿墙雷达时域波束成像分辨率低、旁瓣高以及干扰抑制能力弱等问题,提出利用稳健Capon波束形成对目标成像的方法。该方法基于目标回波模型首先补偿近场扩散损耗、墙体传播损耗和折射效应,实现天线阵列接收数据的配准,利用稳健Capon波束成像得到良好的成像分辨率和更好的干扰抑制能力。利用时域有限差分(finite-difference time domain,FDTD)数值仿真和实验数据实现了隐藏目标的二维成像,验证了该方法的有效性。
