Copper-doped tungstic acid nanocrystals transform infrared light conversion

Nanowerk   September 13, 2023 The technology to utilize the full spectrum of solar radiation is still in its infancy as conventional methods constrain their all-solar response. Researchers in Japan have proposed using – submerged photosynthesis of crystallites (SPsC). They showed that strategic doping with copper and oxygen vacancies can induce opto-critical phases from the non-stoichiometric tungstic acids. These opto-critical phases enabled a dynamic equilibrium shift in lattice defect stabilization, facilitating an unprecedented whole solar wavelength response. The response manifested photo-assisted water evaporation, and photo-electrochemical characteristics. According to the researchers their strategy of harnessing all-solar energy, the one-pot SPsC strategy, may […]

Scientists design novel nonlinear circuit to harvest clean power using graphene

Phys.org  August 18, 2023 An international team of researchers (USA – University of Arkansas, UC Berkeley, Spain) theoretically considered a graphene ripple as a Brownian particle coupled to an energy storage circuit. When circuit and particle are at the same temperature, the second law forbids harvesting energy from the thermal motion of the Brownian particle, even if the circuit contains a rectifying diode. However, when the circuit contains a junction followed by two diodes wired in opposition, the approach to equilibrium may become ultraslow. Detailed balance is temporarily broken as current flows between the two diodes and charges storage capacitors. […]

Wearable textile captures energy from body movement to power devices

Phys.org  June 5, 2023 Some of the energy supply units cannot meet the energy requirements for wearable electronics which requires its energy supply part to be flexible, wearable, integratable and sustainable. Researchers at the Georgia Institute of Technology have developed wearable sustainable energy harvesting-storage hybrid self-charging power textile. The power textile consists of a coaxial fiber-shaped polylactic acid/reduced graphene oxide/polypyrrole (PLA-rGO-PPy), triboelectric nanogenerator (fiber-TENG) which is flexible can harvest low-frequency and irregular energy during human motion, and a novel coaxial fiber-shaped supercapacitor (fiber-SC) as an energy storage unit. The integrated power textile can provide an efficient route for sustainable working […]

Engineers harvest abundant clean energy from thin air, 24/7

Science Daily  May 24, 2023 Previously described technologies for harvesting energy from air humidity are either not continuous or require unique material synthesis or processing, which has stymied scalability and broad deployment. Researchers at UMass developed a generic effect for continuous energy harvesting from air humidity which could be applied to a broad range of inorganic, organic, and biological materials. The materials were engineered with appropriate nanopores to allow air water to pass through and undergo dynamic adsorption–desorption exchange at the porous interface, resulting in surface charging. The top exposed interface experienced the dynamic interaction more than the bottom sealed […]

Solar harvesting system has potential to generate solar power 24/7

Science Daily  October 3, 2022 Traditional solar thermophotovoltaics (STPVs) rely on an intermediate layer to tailor sunlight for better efficiencies. However, the thermodynamic efficiency limit of STPVs is still far lower than the Landsberg limit (93.3%), the ultimate efficiency limit for solar energy harvesting. Researchers at the University of Houston showed that the efficiency deficit is caused by the back emission of the intermediate layer towards the sun resulting from the reciprocity of the system. They proposed nonreciprocal solar thermophotovoltaics (NSTPV) that utilize an intermediate layer with nonreciprocal radiative properties. Such a nonreciprocal intermediate layer could substantially suppress its back […]

Small molecules, giant (surface) potential

Phys.org  August 26, 2022 The performance of organic optoelectronic and energy-harvesting devices is largely determined by the molecular orientation and resultant permanent dipole moment, yet this property is difficult to control during film preparation. Researchers in Japan have demonstrated the active control of dipole direction in organic glassy films by physical vapour deposition. It was obtained by utilizing the small surface free energy of a trifluoromethyl unit and intramolecular permanent dipole moment induced by functional groups. According to the researchers their work could pave a way toward the formation of spontaneously polarized organic glassy films, leading to improvement in the […]

Harvesting energy – drop by drop

Nanowerk  August 25, 2022 In this review article researchers in China summarized the recent developments in droplets-driven nanogenerators for effective energy scavenging. They included an extensive discussion about the device structures from the material selection and output performance aspects. They gave a brief discussion on the applications of droplet-based nanogenerators and outline the future possibilities via the current improvement in designs and fabrication strategies that have been introduced by the field. According to the authors water droplet harvesting as a sustainable energy resource has become a forward-looking step to meet the future demand for green energy. The emerging potential of […]

Washable and recyclable solar cell-infused textiles

Nanowerk   May 21, 2022 Researchers in Finland laminated a solar cell component between textiles in a water-tight polyurethane film to make the component machine-washable. The textiles containing the solar cell component were then washed dozens of times. Five of the eight samples retained their efficiency, and three lost about 20 percent of their power. None of the cells or the textiles were damaged during the process. They used textiles whose fibers were made of only a single material and thus could be recycled as efficiently as possible. Electronic components can be removed from the fabric simply by first applying heat […]

Hidden distortions trigger promising thermoelectric property

Science Daily  May 9, 2022 Conventional structure transitions occur from a low symmetry state to a higher symmetry state upon warming. An international team of researchers (USA – Northwestern University, Brookhaven National Laboratory, Germany) found an unexpected local symmetry breaking in the tetragonal diamondoid compound silver gallium telluride. Upon warming, it evolved continuously from an undistorted ground state to a locally distorted state while retaining average crystallographic symmetry. This is a rare phenomenon previously referred to as emphanisis. The distorted state, caused by the weak orbital hybridization of tetrahedral Ag atoms, resulted in their displacement of the tetrahedron center and […]

The hidden behavior of supercapacitor materials

Phys.org  November 9, 2021 Polyaniline (PANI) is conductive and can be used as the electrode in a supercapacitor device, storing charge by trapping ions. To maximize energy storage, an international team of researchers (UK, Brazil) developed a novel method of depositing a thin layer of PANI onto a forest of conductive carbon nanotubes. This composite material makes an excellent supercapacitive electrode. However, as the composite is made up of different materials, it is difficult to separate and fully understand the complex processes which occur during charging and discharging. The researchers used Distribution of Relaxation Times analysis technique to examine complex […]