SignificanceAutonomy separates robots from machines. Incorporating autonomy into soft robots is an outstanding challenge due to the mismatch between rigid electronics and the compliant bodies. In this work, we demonstrate origami as a platform for compliant mechanical logic, containing mechanical bits, logic gates, and signal transmission mechanisms that can supplement conventional electronic controls. Furthermore, these processes can be responsive to and programmed by the environment via the integration of adaptive materials. Thus, origami provides a framework in which sensing, computation, and reflexes can be seamlessly integrated into the compliant bodies of soft robotics.

A high-throughput method for characterizing the temperature dependence of material properties following microsecond to millisecond thermal annealing, exploiting the temperature gradients created by a lateral gradient laser spike anneal (lgLSA), is presented. Laser scans generate spatial thermal gradients of up to 5 °C/μm with peak temperatures ranging from ambient to in excess of 1400 °C, limited only by laser power and materials thermal limits. Discrete spatial property measurements across the temperature gradient are then equivalent to independent measurements after varying temperature anneals. Accurate temperature calibrations, essential to quantitative analysis, are critical and methods for both peak temperature and spatial/temporal temperature profile characterization are presented. These include absolute temperature calibrations based on melting and thermal decomposition, and time-resolved profiles measured using platinum thermistors. A variety of spatially resolved measurement probes, ranging from point-like continuous profiling to large area sampling, are discussed. Examples from annealing of III-V semiconductors, CdSe quantum dots, low-κ dielectrics, and block copolymers are included to demonstrate the flexibility, high throughput, and precision of this technique.

Adaptive soft materials exhibit a diverse set of behaviors including reconfiguration, actuation, and locomotion. These responses however, are typically optimized in isolation. Here, we establish the interrelation between these behaviors though a state space framework, using Nylon 6 thin films in a humidity gradient as an experimental testbed. We determine that the dynamic behaviors are a result of not only a response to, but also an interaction with the applied stimulus, which can be tuned via control of the environment and film characteristics, including size, permeability and coefficient of hygroscopic expansion to target a desired behavior such as multi-modal locomotion. Using these insights, we

Epitaxially connected assemblies of nanocrystals (NCs) present an interesting new class of nanomaterial in which confinement of charge carriers is intermediate between that of a quantum dot and a quantum well. Despite impressive advances in the formation of high-fidelity assemblies, predicted collective properties have not yet emerged. A critical knowledge gap toward realizing these properties is the current lack of understanding of and control over the formation of epitaxial interdot bonds connecting the NCs within the assemblies. In this work we demonstrate successive ionic layer absorption and reaction (SILAR) to enhance the interdot bonding within the NC assembly. SILAR treatment improved the fraction of interdot bonds from 82% to 91% and increased their width from 3.1 to 4.0 nm. Absorption spectra and charge transport measurements indicate that the effect of postassembly growth on quantum confinement in this system depends on the composition of the SILAR shell material. Increased NC film conductance following SILAR processing indicates that building and strengthening interdot bonds lead to increased electronic coupling and doping in the assemblies. The postassembly film growth detailed here presents an opportunity to repair structural defects and to tailor the balance of quantum confinement and interdot coupling in epitaxially connected NC assemblies.

Binary nanocrystal superlattices present unique opportunities to create novel interconnected nanostructures by partial fusion of specific components of the superlattice. Here, we demonstrate the binary AB6 superlattice of PbSe and Fe2O3 nanocrystals as a model system to transform the central hexamer of PbSe nanocrystals into a single fused particle. We present detailed structural analysis of the superlattices by combining high-resolution X-ray scattering and electron microscopy. Molecular dynamics simulations show optimum separation of nanocrystals in agreement with the experiment and provide insights into the molecular configuration of surface ligands. We describe the concept of nanocrystal superlattices as a versatile ‘nanoreactor' to create and study novel materials based on precisely defined size, composition and structure of nanocrystals into a mesostructured cluster. We demonstrate ‘controlled fusion' of nanocrystals in the clusters in reactions initiated by thermal treatment and pulsed laser annealing.

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Light-triggered reduction and oxidation processes enable isovolumetric reshaping of AuNRs in a polymer matrix and printing of complex patterns with multiple plasmonic characteristics.

As nanocrystal (NC) synthesis techniques and device architectures advance, it becomes increasingly apparent that new ways of connecting NCs with each other and their external environment are required to realize their considerable potential. Enhancing inter-NC coupling by thermal annealing has been a long-standing challenge. Conventional thermal annealing approaches are limited by the challenge of annealing the NC at sufficiently high temperatures to remove surface-bound ligands while at the same time limiting the thermal budget to prevent large-scale aggregation. Here we investigate nonequilibrium laser annealing of NC thin films that enables separation of the kinetic and thermodynamic aspects of nanocrystal fusion. We show that laser annealing of NC assemblies on nano- to microsecond time scales can transform initially isolated NCs in a thin film into an interconnected structure in which proximate dots "just touch". We investigate both pulsed laser annealing and laser spike annealing and show that both annealing methods can produce "confined-but-connected" nanocrystal films. We develop a thermal transport model to rationalize the differences in resulting film morphologies. Finally we show that the insights gained from study of nanocrystal mono- and bilayers can be extended to three-dimensional NC films. The basic processing-structure-property relationships established in this work provide guidance to future advances in creating functional thin films in which constituent NCs can purposefully interact.