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904.
Stefano Mariani Valentina Robbiano Rossella Iglio Antonino A. La Mattina Pantea Nadimi Joanna Wang Byungji Kim Tushar Kumeria Michael J. Sailor Giuseppe Barillaro 《Advanced functional materials》2020,30(4)
In this work, both light‐shaping and image magnification features are integrated into a single lens element using a moldless procedure that takes advantage of the physical and optical properties of mesoporous silicon (PSi) photonic crystal nanostructures. Casting of a liquid poly(dimethylsiloxane) pre‐polymer solution onto a PSi film generates a droplet with a contact angle that is readily controlled by the silicon nanostructure, and adhesion of the cured polymer to the PSi photonic crystal allows preparation of lightweight (10 mg) freestanding lenses (4.7 mm focal length) with an embedded optical component (e.g., optical rugate filter, resonant cavity, and distributed Bragg reflector). The fabrication process shows excellent reliability (yield 95%) and low cost and the lens is expected to have implications in a wide range of applications. As a proof‐of‐concept, using a single monolithic lens/filter element it is demonstrated: fluorescence imaging of isolated human cancer cells with rejection of the blue excitation light, through a lens that is self‐adhered to a commercial smartphone; shaping of the emission spectrum of a white light emitting diode to tune the color from red through blue; and selection of a narrow wavelength band (bandwidth 5 nm) from a fluorescent molecular probe. 相似文献
905.
Stefanie Lochmann Yannik Bruniger Vincent Gottsmann Lydia Galle Julia Grothe Stefan Kaskel 《Advanced functional materials》2020,30(19)
A novel three‐electrode electrolyte supercapacitor (electric double‐layer capacitor [EDLC]) architecture in which a symmetrical interdigital “working” two‐electrode micro‐supercapacitor array (W‐Cap) is paired with a third “gate” electrode that reversibly depletes/injects electrolyte ions into the system controlling the “working” capacity effectively is described. All three electrodes are based on precursor‐derived nanoporous carbons with well‐defined specific surface area (735 m2 g?1). The interdigitated architecture of the W‐Cap is precisely manufactured using 3D printing. The W‐Cap operating with a proton conducting PVA/H2SO4‐hydrogel electrolyte and high capacitance (6.9 mF cm?2) can be repeatedly switched “on” and “off”. By applying a low DC bias potential (?0.5 V) at the gate electrode, the AC electroadsorption in the coupled interdigital nanoporous carbon electrodes of the W‐Cap is effectively suppressed leading to a stark capacity drop by two orders of magnitude from an “on” to an “off” state. The switchable micro‐supercapacitor is the first of its kind. This general concept is suitable for implementing a broad range of nanoporous materials and advanced electrolytes expanding its functions and applications in future. The integration of intelligent functions into EDLC devices has extensive implications for diverse areas such as capacitive energy management, microelectronics, iontronics, and neuromodulation. 相似文献
906.
Jieqiong Qin Jianmei Gao Xiaoyu Shi Junyu Chang Yanfeng Dong Shuanghao Zheng Xiao Wang Liang Feng Zhong‐Shuai Wu 《Advanced functional materials》2020,30(16)
Planar integrated systems of micro‐supercapacitors (MSCs) and sensors are of profound importance for 3C electronics, but usually appear poor in compatibility due to the complex connections of device units with multiple mono‐functional materials. Herein, 2D hierarchical ordered dual‐mesoporous polypyrrole/graphene (DM‐PG) nanosheets are developed as bi‐functional active materials for a novel prototype planar integrated system of MSC and NH3 sensor. Owing to effective coupling of conductive graphene and high‐sensitive pseudocapacitive polypyrrole, well‐defined dual‐mesopores of ≈7 and ≈18 nm, hierarchical mesoporous network, and large surface area of 112 m2 g?1, the resultant DM‐PG nanosheets exhibit extraordinary sensing response to NH3 as low as 200 ppb, exceptional selectivity toward NH3 that is much higher than other volatile organic compounds, and outstanding capacitance of 376 F g?1 at 1 mV s?1 for supercapacitors, simultaneously surpassing single‐mesoporous and non‐mesoporous counterparts. Importantly, the bi‐functional DM‐PG‐based MSC‐sensor integrated system represents rapid and stable response exposed to 10–40 ppm of NH3 after only charging for 100 s, remarkable sensitivity of NH3 detection that is close to DM‐PG‐based MSC‐free sensor, impressive flexibility with ≈82% of initial response value even at 180°, and enhanced overall compatibility, thereby holding great promise for ultrathin, miniaturized, body‐attachable, and portable detection of NH3. 相似文献
907.
Hyunhak Jeong Haipeng B. Li Lucas Domulevicz Joshua Hihath 《Advanced functional materials》2020,30(28)
Systems that are capable of robustly reproducing single‐molecule junctions are an essential prerequisite for enabling the wide‐spread testing of molecular electronic properties, the eventual application of molecular electronic devices, and the development of single‐molecule based electrical and optical diagnostics. Here, a new approach is proposed for achieving a reliable single‐molecule break junction system by using a microelectromechanical system device on a chip. It is demonstrated that the platform can (i) provide subnanometer mechanical resolution over a wide temperature range (≈77–300 K), (ii) provide mechanical stability on par with scanning tunneling microscopy and mechanically controllable break junction systems, and (iii) operate in a variety of environmental conditions. Given these fundamental device performance properties, the electrical characteristics of two standard molecules (hexane‐dithiol and biphenyl‐dithiol) at the single‐molecule level, and their stability in the junction at both room and cryogenic temperatures (≈77 K) are studied. One of the possible distinctive applications of the system is demonstrated, i.e., observing real‐time Raman scattering in a single‐molecule junction. This approach may pave a way to achieving high‐throughput electrical characterization of single‐molecule devices and provide a reliable platform for the convenient characterization and practical application of single‐molecule electronic systems in the future. 相似文献
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微惯性姿态测量系统机械精度不高、系统误差和随机误差干扰多样和传统标定计算复杂。针对这些问题,提出一种新型微惯性姿态测量系统误差标定的方法。通过对姿态测量系统的不同微惯性器件进行分析,有针对性的建立系统误差补偿模型。再设置实验转台给定系统不同速率及角度,最后利用最小二乘法、六位置标定法分别进行系统误差参数求解,经解算标定出零位漂移、刻度因子误差和安装误差角。最后通过标定前后对比测试实验,证明了该方法原理简单、易于实现,能较好地补偿微惯性姿态测量系统的系统误差,提高姿态测量精度。 相似文献
910.
Hyo‐Min Kim Misun Ryu James H.J. Cha Hyun Soo Kim Tak Jeong Jin Jang 《Journal of the Society for Information Display》2019,27(6):347-353
A fine patternable quantum dots (QDs) color conversion layer (CCL) for high resolution and full color active matrix (AM) micro‐LED (μ‐LED) display is demonstrated. QDs CCL could be patterned until 10 μm using photolithography process. It is found that multicoatings with red and green QDs (R‐ and G‐QDs) CCLs on LED array can provide full color AM display. 相似文献