Phys.org December 17, 2024 The synergistic integration of all the components for efficient light harvesting, cascade electron transfer, and efficient biocatalytic reactions presents a formidable challenge. Researchers in the UK described the bottom-up construction of a visible-light-driven chemical–biological hybrid nanoreactor with augmented photocatalytic efficiency by anchoring an α-carboxysome shell encasing on the surface of a hydrogen-bonded organic molecular crystal, a microporous α-polymorph of tetra(4′-carboxyphenyl)pyrene (TBAP-α). Within this hybrid photobiocatalyst, TBAP-α functioned as an antenna for visible-light absorption and exciton generation, supplying electrons for hydrogen production by H–S in aqueous solutions. This coordination allowed the hybrid nanoreactor to execute hydrogen evolution […]
Tag Archives: Biomimetics
Bioinspired hydrogels harness sunlight: A step closer to artificial photosynthesis
Phys.org November 6, 2024 Aquatic environments host various living organisms with active molecular systems that realize photosynthesis. Researchers in Japan addressed the significant challenges in using polymer networks as active mediators for photoinduced water splitting. They incorporated various features offered by artificial chloroplasts polymer networks for stepwise synthesis and integration during the hierarchical construction. The constituent molecules were closely arranged to smoothly operate forward reactions by polymer networks. The quantum efficiency of photoinduced H2 generation in gel systems was higher than that of conventional solution systems. Additionally, a thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) network of microgels could be used to integrate catalytic […]
Self-propelled shape-changing robots mimic aquatic insects for untethered swimming
Nanowerk October 8, 2024 Despite recent advances in the field of small-scale robots, the development of efficient, untethered, and integrated powering, actuation, and control of small-scale robots remains a challenge due to the out-of-equilibrium and dissipative nature of the driving physical and chemical phenomena. An international team of researchers (USA – University of Michigan, Canada) designed small-scale, bioinspired aquatic locomotors with programmable deterministic trajectories that integrated self-propelled chemical motors and photoresponsive shape-morphing structures. They developed robots integrating structural protein networks that self-regulated the release of chemical fuel with photochemical liquid crystal network (LCN) actuators that changed their shape and deformed […]
Bioinspired yarn can harvest water from fog
Phys.org September 30, 2024 An international team of researchers (Italy, Germany, Sweden, Japan) developed a double-strand hydrophobic PVDF-HFP/hydrophilic PAN nanofibers yarn by electrospinning and twisting techniques like the hydrophobic/hydrophilic pattern of desert beetles and water self-propulsion property of spider silks. The double-strand cooperation approach allowed for water deposition on hydrophobic PVDF-HFP segment and transport under the asymmetric capillary driving force of hydrophilic PAN segment speeding up the aggregation and growth of droplets. They optimized the effects of the composition and the diameter ratio of the two primary yarns for boosting fog collection performance. The double-strand anisotropic yarn provided an effective […]
Physicists discover a new optical property that measures the twist in tiny helicesÂ
Phys.org June 17, 2024 Biomimetic nanotechnology and self-assembly advances need chirality. There is a need to develop general methods to characterize chiral building blocks at the nanoscale in liquids such as water. An international team of researchers (UK, Italy, USA – University of Nebraska, Pennsylvania State University) observed chiroptical second-harmonic Tyndall scattering effect in high-refractive-index dielectric nanomaterial Si nanohelices. They provided a theoretical analysis that explained the origin of the effect and its direction dependence, resulting from different specific contributions of “electric dipole–magnetic dipole” and “electric dipole–electric quadrupole” coupling tensors. They narrowed down the number of such terms to 8 […]
Innovative bird-eye-inspired camera developed for enhanced object detection
Science Daily May 30, 2024 Despite notable advances in artificial vision systems that mimic animal vision, the exceptional object detection and targeting capabilities of avian eyes via foveated and multispectral imaging remain underexplored. Researchers in South Korea have developed an artificial vision system that capitalizes on these aspects of avian vision by vertically stacking perovskite photodetector arrays whose designs were optimized by theoretical simulations for the demonstration of foveated and multispectral imaging. The artificial vision system successfully identified colored and mixed-color objects and detected remote objects through foveated imaging. They discussed the potential for its use in uncrewed aerial vehicles […]
Waterproof ‘e-glove’ could help scuba divers communicate
Nanowerk April 10, 2024 Existing tactile sensing gloves fall short in terms of user comfort and are ill-suited for underwater applications. Researchers in China proposed and constructed a flexible hand gesture recognition glove (GRG) that contained high-performance micropillar tactile sensors (MPTSs) inspired by the flexible tube foot of a starfish. The sensor has a wide working range, superfast response time, reliable repeatability, and a low limit of detection and they were waterproof. When integrated with machine learning algorithm, the GRG system achieved intelligent recognition of 16 hand gestures under water, extending real-time and effective communication capabilities for divers. According to […]
Backyard insect inspires invisibility devices, next gen tech
Phys.org March 18, 2024 The leafhoppers cover their body surfaces with brochosomes, buckyball-shaped, nanoscopic spheroids with through-holes distributed across their surfaces, representing a class of deployable optical materials that are rare in nature. A team of researchers in the US (University of Pennsylvania, Carnegie Mellon University) investigated the optical form-to-function relationship of brochosomes and demonstrated that the hierarchical geometries of brochosomes are engineered within a narrow size range with through-hole architecture to significantly reduce light reflection. They showed that the diameters of brochosomes are engineered to maximize broadband light scattering, while the secondary through-holes are designed to function as short-wavelength, […]
Unveiling the invisible: A bioinspired CMOS-integrated polarization imaging sensor
Phys.org September 18, 2023 Chip-integrated, fast, cost-effective, and accurate full-Stokes polarimetric imaging sensors are highly desirable in many applications, but they remain elusive due to fundamental material limitations. Researchers at the State University of Arizona have developed a chip-integrated Metasurface-based Full-Stokes Polarimetric Imaging sensor (MetaPolarIm) by integrating an ultrathin (~600 nm) metasurface polarization filter array (MPFA) onto a visible imaging sensor with CMOS compatible fabrication processes. The MPFA has broadband dielectric-metal hybrid chiral metasurfaces and double-layer nanograting polarizers. This chip-integrated polarimetric imaging sensor enabled single-shot full-Stokes imaging (speed limited by the CMOS imager) with the most compact form factor, recorded high […]
New textile unravels warmth-trapping secrets of polar bear fur
Science Daily April 10, 2023 There are evidence that polar-dwelling animals have evolved a different mechanism of thermoregulation by using optical polymer materials to achieve an on-body “greenhouse” effect. Researchers at UMass Amherst designed a bilayer textile to mimic these adaptations. They showed that two ultralightweight fabrics with complementary optical functions, a polypropylene visible-transparent insulator and a nylon visible-absorber–infrared-reflector coated with a conjugated polymer, performed the same putative function as polar bear hair and skin, respectively. While retaining familiar textile qualities, these layers suppressed dissipation of body heat and maximized radiative absorption of visible light. Under moderate illumination of 130 […]