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The rapid development of micro/nanomanipulation technologies has opened unprecedented opportunities for the sorting, assembly, and actuation of biological and inorganic entities for applications ranging from live‐cell separation, drug screening, biosensing to micro/nanomachines and nanorobots. To this end, remarkable progress has been made in the development of efficient, precise, and versatile nanomanipulation techniques based on individual or combined chemical and physical fields. Among them, techniques that fuse light stimuli with electric (E) fields, have achieved impressive performance in the versatility, reconfigurability, and throughput in the manipulation of both biological and inorganic micro/nanoscale objects compared to those of many other manipulation techniques, by leveraging the strong optoelectric coupling effect of semiconductor materials. This work provides a review of various types of light‐gated electric manipulation systems – the working principles, experimental setups, limitations, applications, and future perspectives. [ABSTRACT FROM AUTHOR]

Abstract: The practical applications of wearable electronics rely on the successful development of flexible and integrable energy devices with small footprints. This work reports a completely new type of graphite foam made of strategically created superstructures with covalently attached diverging microtubes, and their applications as electrode supports for binder‐free and additive‐free flexible supercapacitors. Because of the enhanced volumetric surface areas compared to conventional graphite foams, a high loading of pseudocapacitive materials (Mn3O4, 3.91 mg cm−2, 78 wt%) is achieved. The supercapacitors provide areal capacitances as high as 820 mF cm−2 at 1 mV s−1, while still maintaining high rate capability and 88% retention of capacitance after 3000 continuous charging and discharging cycles. When assembled as all‐solid‐state flexible symmetric supercapacitors, they offer one of the highest full‐cell capacitances (191 mF cm−2) among similar manganese oxide/graphene foams, and retain 80% capacitance after 1000 mechanical cycles. The potential of such flexible supercapacitors is also manifested by directly powering electric nanomotors that can trace along letters “U” and T,” which is the first demonstration of flexible supercapacitors for wireless/portable nanomanipulation systems. This work could inspire a new paradigm in designing and creating 3D porous micro/nanosuperstructures for an array of self‐powered electronic and nanomechanical applications. [ABSTRACT FROM AUTHOR]

It is highly desirable to precisely tune the molecule release rate from the surfaces of nanoparticles (NPs) that are relevant to cancer therapy and single-cell biology. An innovative mechanism is reported to actively tune the biochemical release rate by rotation of NPs. Plasmonic nanomotors were assembled from NPs and applied in multiplex biochemical release and detection. Both single and multiplex biosignals can be released in a tunable fashion by controlling the rotation speed of the nanomotors. The chemistry and release rate of individual chemicals can be revealed by Raman spectroscopy. The fundamental mechanism was modeled quantitatively and attributed to the fluidic boundary-layer reduction owing to the liquid convection. This work, which explored the synergistic attributes of surface enhanced Raman scattering and nanoelectromechanical systems, could inspire new sensors that are potentially interesting for various bio-applications. [ABSTRACT FROM AUTHOR]

To develop active nanomaterials that can instantly respond to external stimuli with designed mechanical motions is an important step towards the realization of nanorobots. Herein, we present our finding of a versatile working mechanism that allows instantaneous change of alignment direction and speed of semiconductor nanowires in an external electric field with simple visible-light exposure. The light induced alignment switch can be cycled over hundreds of times and programmed to express words in Morse code. With theoretical analysis and simulation, the working principle can be attributed to the optically tuned real-part (in-phase) electrical polarization of a semiconductor nanowire in aqueous suspension. The manipulation principle is exploited to create a new type of microscale stepper motor that can readily switch between in-phase and out-phase modes, and agilely operate independent of neighboring motors with patterned light. This work could inspire the development of new types of micro/nanomachines with individual and reconfigurable maneuverability for many applications. Developing active nanomaterials that can instantly respond to external stimuli with designed mechanical motions for nanorobotics applications remains a challenge. Here, the authors propose a Si-NWs light programmable nanomotors design based on optically tunable in-phase electric polarization. [ABSTRACT FROM AUTHOR]