The photothermal Marangoni effect enables direct light-to-work conversion, which is significant for realizing the self-propulsion of objects in a noncontact, controllable, and continuous manner. Many promising applications have been demonstrated in micro- and nanomachines, light-driven actuators, cargo transport, and gear transmission. Currently, the related studies about photothermal Marangoni effect-induced self-propulsion, especially rotational motions, remain focused on developing the novel photothermal materials, the structural designs, and the controllable self-propulsion modes. However, extending the related research from the laboratory practice to practical application remains a challenge. Herein, we combined the photothermal Marangoni effect-induced self-propulsion with the triboelectric nanogenerator technology for sunlight intensity determination. Photothermal black silicon, superhydrophobic copper foam with drag-reducing property, and triboelectric polytetrafluoroethylene film were integrated to fabricate a triboelectric nanogenerator. The photothermal-Marangoni-driven triboelectric nanogenerator (PMD-TENG) utilizes the photothermal Marangoni effect-induced self-propulsion to realize the relative motion between the triboelectric layer and the electrode, converting light into electrical signals, with a peak value of 2.35 V. The period of the output electrical signal has an excellent linear relationship with the light intensity. The accessible electrical signal generation strategy proposed here provides a new application for the photothermal Marangoni effect, which could further inspire the practical applications of the self-powered system based on the photothermal Marangoni effect, such as intelligent farming.
Di Qiao,Yihao Guan,Dan Zhang,Bingqian Bi,Yiming Li
The efficient treatment of oil spills still remains a worldwide challenge. Traditional hydrophobic absorbents show limitation in absorbing high-viscosity crude oil. Fortunately, increasing the temperature of crude oil is an effective way to enhance its fluidity. Photo-thermal sorbents can convert solar-energy into heat-energy, which can be utilized to increase the crude oil's temperature. We prepared a solar-thermal polystyrene foam (CG-PDMS@PS) from a high internal phase emulsion (HIPE) method. Carbon black and graphene are embedded in the foam to facilitate rapid photo-thermal conversion and the temperature of the foam can reach 79.9 °C under 1.0 kW m−2. Additionally, the introduction of PDMS and graphene enhanced the mechanical properties of the foam. The CG-PDMS@PS foam exhibits super-hydrophobic characteristic even in strong acids and alkaline solutions. For the high-viscosity crude oil, the CG-PDMS@PS foam can reduce its viscosity and achieve rapid adsorption with the assistance of sunlight. We systematically investigated the effects of sunlight intensity and oil-viscosity on the adsorption of crude oil and analyzed the vertical heat transfer capacity and the sinking rate of the foam. Furthermore, the CG-PDMS@PS foam can also be applied in the continuous recovery of oil spills. In view of its unique properties, the CG-PDMS@PS foam provides a new solution to address oil spills.
Highly sensitive sensors with extensive applications are extremely desired in the next-generation wearable electronics for human motion monitoring, human-machine interface and intelligent robotics, while single-functional pressure sensors cannot fulfill the growing demands of modern technological advances. Herein, an all-fabric and multilayered piezoresistive sensor based on conductive metal-organic framework/layered double hydroxide (cMOF/LDH) hetero-nanoforest is demonstrated to achieve multiple applications including pulse detection, joint motion detection, sound detection and information transmission. Benefiting from the synergism of cMOF/LDH hetero-nanoforest and multilayered structure, the sensor exhibits a high sensitivity (1.61×10 9 kPa −1 ) over a broad pressure range (0-100 kPa), a fast response/recovery time (71 ms/71 ms) and a low detection limit (18 Pa), as well as reliable dynamic stability (8000 cycles). It is gratifying to note that the introduction of cMOFs endows the sensor with the potential to detect the concentration of NH 3 (1-100 ppm) and sunlight intensity (10-100 mW cm −2 ). This work shows great potential in multifunctional sensing, which enlightens a strategy for advancing the development process of highly sensitive intelligent wearable devices.
危险品化学品经营许可证（带存储）