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Abstract Microbubbles are an important tool due to their unique mechanical, acoustic, and dynamical properties. Yet, it remains challenging to generate microbubbles quickly in a parallel, biocompatible, and controlled manner. Here, we present an opto-electrochemical method that combines precise light-based projection with low-energy electrolysis, realizing defined microbubble patterns that in turn trigger assembly processes. The size of the bubbles can be controlled from a few to over hundred micrometers with a spatial accuracy of ~2 μm. The minimum required light intensity is only ~0.1 W/cm², several orders of magnitude lower compared to other light-enabled methods. We demonstrate the assembly of prescribed patterns of 40-nm nanocrystals, 200 nm extracellular vesicles, polymer nanospheres, and live bacteria. We show how nanosensor-bacterial-cell arrays can be formed for spectroscopic profiling of metabolites and antibiotic response of bacterial assemblies. The combination of a photoconductor with electrochemical techniques enables low-energy, low-temperature bubble generation, advantageous for large-scale, one-shot patterning of diverse particles in a biocompatible manner. The microbubble-platform is highly versatile and promises new opportunities in nanorobotics, nanomanufacturing, high-throughput bioassays, single cell omics, bioseparation, and drug screening and discovery. 

The rapid advancement of nanotweezers for wireless manipulation of artificial micro‐ and nanoparticles has unlocked unprecedented possibilities in biomedicine. This review delves into optical, electric, and magnetic tweezers, emphasizing their roles in controlling single particles with micro/nanoscale features as miniaturized tools. Instead of providing a comprehensive review, this work highlights a select number of representative historical and contemporary examples of each type of tweezer, covering their rudimental working mechanisms, experimental setups, performance characteristics, and niche biomedical applications. Particularly, the focus lies in providing a quantitative comparison of the performances in spatial precision and degrees of freedom in controlling single particles, along with associated challenges and prospects. 

Abstract Mechanically programmable, reconfigurable micro/nanoscale materials that can dynamically change their mechanical properties or behaviors, or morph into distinct assemblies or swarms in response to stimuli have greatly piqued the interest of the science community due to their unprecedented potentials in both fundamental research and technological applications. To date, a variety of designs of hard and soft materials, as well as actuation schemes based on mechanisms including chemical reactions and magnetic, acoustic, optical, and electric stimuli, have been reported. Herein, state‐of‐the‐art micro/nanostructures and operation schemes for multimodal reconfigurable micro/nanomachines and swarms, as well as potential new materials and working principles, challenges, and future perspectives are discussed. 

Abstract Bulk transition metal dichalcogenide (TMDC) nanostructures are regarded as promising material candidates for integrated photonics due to their high refractive index at the near‐infrared wavelengths. In this work, colloidal TMDC waveguides with tailorable dimensions are prepared by a scalable synthetic approach. The optical waveguiding properties of colloidal nanowires are studied by the near‐field nanoimaging technique. In addition to dependence on thickness and wavelength, the excitonic responses and resultant waveguide modes in TMDC nanowires can be modulated by the environmental temperature. With the high‐throughput production and tunable optical properties, colloidal TMDC nanowires highlight the potential for active optical components and integrated photonic devices. 

Abstract 2D transition‐metal‐dichalcogenide materials, such as molybdenum disulfide (MoS₂) have received immense interest owing to their remarkable structure‐endowed electronic, catalytic, and mechanical properties for applications in optoelectronics, energy storage, and wearable devices. However, 2D materials have been rarely explored in the field of micro/nanomachines, motors, and robots. Here, MoS₂ with anatase TiO₂ is successfully integrated into an original one‐side‐open hollow micromachine, which demonstrates increased light absorption of TiO₂‐based micromachines to the visible region and the first observed motion acceleration in response to ionic media. Both experimentation and theoretical analysis suggest the unique type‐II bandgap alignment of MoS₂/TiO₂ heterojunction that accounts for the observed unique locomotion owing to a competing propulsion mechanism. Furthermore, by leveraging the chemical properties of MoS₂/TiO₂, the micromachines achieve sunlight‐powered water disinfection with 99.999% Escherichia coli lysed in an hour. This research suggests abundant opportunities offered by 2D materials in the creation of a new class of micro/nanomachines and robots. 

Abstract Subwavelength optical resonators with spatiotemporal control of light are essential to the miniaturization of optical devices. In this work, chemically synthesized transition metal dichalcogenide (TMDC) nanowires are exploited as a new type of dielectric nanoresonators to simultaneously support pronounced excitonic and Mie resonances. Strong light–matter couplings and tunable exciton polaritons in individual nanowires are demonstrated. In addition, the excitonic responses can be reversibly modulated with excellent reproducibility, offering the potential for developing tunable optical nanodevices. Being in the mobile colloidal state with highly tunable optical properties, the TMDC nanoresonators will find promising applications in integrated active optical devices, including all‐optical switches and sensors. 

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. 

Self‐powered untethered robots that can meander unrestrictedly, squeeze into small spaces, and operate in diverse harsh environments have received immense attention in recent years. As there is not a universal solution that can be applied to power robots with diverse forms, service functions, and a broad size range from nanometers to meters, the design, fabrication, and implementation of power systems with a suitable weight, desired power and operation duration, and adaptiveness to confined spaces and operation conditions represent one of the greatest challenges in robotic research. Herein, an overview of recent progress and challenges in developing the next‐generation energy harvesting and storage technologies is provided, including direct energy harvesting, energy storage and conversion, and wireless energy transmission for robots across all scales. 

Abstract Molybdenum disulfide (MoS₂) is a multifunctional material that can be used for various applications. In the single‐crystalline form, MoS₂shows superior electronic properties. It is also an exceptionally useful nanomaterial in its polycrystalline form with applications in catalysis, energy storage, water treatment, and gas sensing. Here, the scalable fabrication of longitudinal MoS₂nanostructures, i.e., nanoribbons, and their oxide hybrids with tunable dimensions in a rational and well‐reproducible fashion, is reported. The nanoribbons, obtained at different reaction stages, that is, MoO₃, MoS₂/MoO₂hybrid, and MoS₂, are fully characterized. The growth method presented herein has a high yield and is particularly robust. The MoS₂nanoribbons can readily be removed from its substrate and dispersed in solution. It is shown that functionalized MoS₂nanoribbons can be manipulated in solution and assembled in controlled patterns and directly on microelectrodes with UV‐click‐chemistry. Owing to the high chemical purity and polycrystalline nature, the MoS₂nanostructures demonstrate rapid optoelectronic response to wavelengths from 450 to 750 nm, and successfully remove mercury contaminants from water. The scalable fabrication and manipulation followed by light‐directed assembly of MoS₂nanoribbons, and their unique properties, will be inspiring for device fabrication and applications of the transition metal dichalcogenides.