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Robotics applications are greatly needed in hazardous locations, e.g., fusion and fission reactors, where robots must perform delicate and complex tasks under ionizing radiation conditions. The drawback is that some robotic parts, such as active electronics, are susceptible to radiation. It can lead to unexpected failures and early termination of the robotic operation. This paper analyses the ionizing radiation effect from 0.09 to 1.5 Gy/s in robotic components (microcontrollers, servo motors and temperature sensors). The first experiment compares the performance of various microcontroller types and their actuators and sensors, where different mitigation strategies are applied, such as using Radiation-Hardened (Rad-Hard) microcontrollers or shielding. The second and third experiments analyze the performance of a 3-Degrees of Freedom (DoF) robotic arm, evaluating its componentsʼ responses and trajectory. This study enhances our understanding and expands our knowledge regarding radiationʼs impact on robotic arms and components, which is useful for defining the best strategies for extending the robotsʼ operational lifespan, especially when performing maintenance or inspection tasks in radiation environments.

Despite rapid progress of hybrid organic-inorganic halide perovskite solar cells, using transmission electron microscopy to study their atomic structures has not been possible because of their extreme sensitivity to electron beam irradiation and environmental exposure. Here, we develop cryoelectron microscopy (cryo-EM) protocols to preserve an extremely sensitive perovskite, methylammonium lead iodide (MAPbI3) under various operating conditions for atomic-resolution imaging. We discover the precipitation of lead iodide nanoparticles on MAPbI3nanowire’s surface after short UV illumination and surface roughening after only 10 s exposure to air, while these effects remain undetected in conventional X-ray diffraction. We establish a definition for critical electron dose and find this value for MAPbI3at cryogenic condition to be 12 e−/Å2at 1.49 Å spatial resolution. Our results highlight the importance of cryo-EM since traditional techniques cannot capture important nanoscale changes in morphology and structure that have important implications for perovskite solar cell stability and performance.

The annealing kinetics of the primary electronic F-type color centers (oxygen vacancies with trapped one or two electrons) is analyzed for three ionic materials (Al2O3, MgO, and MgF2) exposed to intensive irradiation by electrons, neutrons, and heavy swift ions. Phenomenological theory of diffusion-controlled recombination of the F-type centers with much more mobile interstitial ions (complementary hole centers) allows us to extract from experimental data the migration energy of interstitials and pre-exponential factor of diffusion. The obtained migration energies are compared with available first-principles calculations. It is demonstrated that with the increase of radiation fluence both the migration energy and pre-exponent are decreasing in all three materials, irrespective of the type of irradiation. Their correlation satisfies the Meyer–Neldel rule observed earlier in glasses, liquids, and disordered materials.The origin of this effect is discussed. This study demonstrates that in the quantitative analysis of the radiation damage of real materials the dependence of the defect migration parameters on the radiation fluence plays an important role and cannot be neglected.

Host-guest interactions govern the chemistry of a broad range of functional materials, but direct imaging using conventional transmission electron microscopy has not been possible. This problem is exacerbated in metal-organic framework materials, which are easily damaged by the electron beam. Here, we use cryogenic electron microscopy (cryo-EM) to stabilize the host-guest structure and resolve the atomic surface of zeolitic imidazolate framework (ZIF-8) and its interaction with guest CO2molecules. We image step-edge sites on the ZIF-8 surface that provide insight to its growth behavior. Furthermore, we observe two distinct binding sites for CO2within the ZIF-8 pore, which are predicted by density functional theory to be energetically favorable. This CO2insertion induces an apparent ∼3% lattice expansion along the <002> and <011> directions of the ZIF-8 unit cell. The ability to stabilize and preserve host-guest chemistry opens a rich materials space for scientific exploration and discovery using cryo-EM.

The OH‐and OD‐stretching frequencies in magnesium‐doped aluminum oxide crystals were determined by infrared absorption measurements. Two very broad bands centered at }3005 and 2228 cm‐1were observed for OH‐and OD‐, respectively. Polarization experiment results were compatible with OH‐(OD‐) ions lying in the basal plane, as is the case in undoped crystals. The threshold temperature for the in‐diffusion of deuterons was obtained by annealing the samples in flowing D2O vapor; the resulting value was }1050 K. At 1223 K, the diffusion coefficient was }3× 10‐7cm2/s, and the activation energy was 1.6 eV.

A volume and phase focusing holographic grating to be used as the principal element of a high-resolution spectrometer has been designed with the aid of a computer. A two-step method was used; first designs were obtained with an aberration-balancing technique, and, in the second step, these early designs are optimized by a ray tracing procedure to obtain aberration-balanced high-efficiency holograms that can be used in high-resolution spectroscopy.

The development of clean energy generation, transmission, and distribution technology, for example, high energy density batteries and high efficiency solar cells, is critical to the progress toward a sustainable future. Such advancement in both scientific understanding and technological innovations entail an atomic- and molecular-resolution understanding of the key materials and fundamental processes governing the operation and failure of the systems. These dynamic processes span multiple length and time scales bridging materials and interfaces involved across the entire device architecture. However, these key components are often highly sensitive to air, moisture, and electron-beam radiation and therefore remain resistant to conventional nanoscale interrogation by electron-optical methods, such as high-resolution (scanning) transmission electron microscopy and spectroscopy.