Energy harvester

Inverted singlet-triplet gap (INVEST) materials have promising photophysical properties for optoelectronic applications due to an inversion of their lowest singlet (S1 ) and triplet (T1 ) excited states. This results in an exothermic reverse intersystem crossing (rISC) process that potentially enhances triplet harvesting, compared to thermally activated delayed fluorescence (TADF) emitters with endothermic rISCs. However, the processes and phenomena that facilitate conversion between excited states for INVEST materials are underexplored...

In the past decade, organic electrosynthesis has emerged as an atom- and energy-efficient strategy for harvesting renewable electricity that provides exceptional control over the reaction parameters. A profound and fundamental understanding of electrochemical interfaces becomes imperative to advance the knowledge-based development of electrochemical processes. The major strategy toward an efficient electrochemical system is based on the advancement in material science for electrocatalysis. Studies on the complex interplay among electrode surface, electrolyte, and transformation intermediates have only recently started to emerge...

Triboelectric nanogenerators (TENGs) are of great significance as sustainable power sources that harvest energy from the human body and environment. Nevertheless, due to TENG's impedance-dependent output voltage characteristics, in traditional strategy (TS), real-timely powering a sensor with TENG has a poor sensing on/off ratio (or response), and directly charging a capacitor with TENG shows a low charging efficiency. This degraded real-time powering and charging performance of TENG compared to a commercial constant voltage source has been a huge challenge of the TENG field for a long time...

This work proposes a monostable symmetric piezoelectric energy harvester based on the cantilever structure and magnetic excitation action (M-PEH). The governing equations of M-PEH are derived based on its kinematic properties. The intrinsic frequency of the piezoelectric cantilever beam was obtained by modal simulation. It has been demonstrated that the mode of arrangement of the magnetic poles has a significant effect on the output voltage of the energy harvester. The proposed M-PEH has four driving magnets with a mass of 6 g and a radial driving distance of 15 mm for more efficient energy harvesting...

Solar energy, as a renewable energy source, dominates the vast majority of human energy, which can be harvested and converted by photovoltaic solar cells. However, the intermittent availability of solar energy restricts the actual utilization circumstances of solar cells. Integrating photo-responsive electrodes into an energy storage device emerges as a dependable and executable strategy, fostering the creation of photo-stimulated batteries that seamlessly amalgamate the process of solar energy collection, conversion, and storage in one system...

Non-linear pyroelectric energy harvesting using ferroelectric thin films exhibits high energy conversion, primarily due to their large breakdown field compared to bulks. Here, we report the pyroelectric energy conversion potential of lead scandium tantalate, Pb(Sc1/2 Ta1/2 )O3 (PST) thin film fabricated on a c-sapphire substrate using chemical solution deposition. To enable the application of high electric field and to assess the pyroelectric energy conversion performance, interdigitated electrodes were deposited on the PST thin film...

The use of sustainable and safe materials is increasingly in demand for the creation of photonic-based technology. Piezoelectric peptide nanotubes make up a class of safe and sustainable materials. We show that these materials can generate piezoelectric charge through the deformation of oriented molecular dipoles when the tube length is flexed through the application of sound energy. Through the combination of peptide nanotubes with plasmon active nanomaterials, harvesting of low-frequency acoustic sound waves was achieved...

Ionic cocrystals with hydrogen bonding can form exciting materials with enhanced optical and electronic properties. We present a highly moisture-stable ammonium salt cocrystal [CH3 C6 H4 CH(CH3 )NH2 ][CH3 C6 H4 CH(CH3 )NH3 ][PF6 ] ( ( p -TEA)( p -TEAH)·PF 6 ) crystallizing in the polar monoclinic C 2 space group. The asymmetry in ( p -TEA)( p -TEAH)·PF 6 was induced by its chiral substituents, while the polar order and structural stability were achieved by using the octahedral PF6 - anion and the consequent formation of salt cocrystal...

Ionogels have grabbed significant interest in various applications, from sensors and actuators to wearable electronics and energy storage devices. However, current ionogels suffer from low strength and poor ionic conductivity, limiting their performance in practical applications. Here, inspired by the mechanical reinforcement of natural biomacromolecules through noncovalent aggregates, a strategy is proposed to construct nanofibril-based ionogels through complex coacervation-induced assembly. Cellulose nanofibrils (CNFs) can bundle together with poly(ionic liquid) (PIL) to form a superstrong nanofibrous network, in which the ionic liquid (IL) can be retained to form ionogels with high liquid inclusion and ionic conductivity...

Transverse thermoelectric effect, the conversion of longitudinal heat current into transverse electric current, or vice versa, offers a promising energy harvesting technology. Materials with axis-dependent conduction polarity, known as p × n-type conductors or goniopolar materials, are potential candidate, because the non-zero transverse elements of thermopower tensor appear under rotational operation, though the availability is highly limited. Here, we report that a ternary metal LaPt2 B with unique crystal structure exhibits axis-dependent thermopower polarity, which is driven by mixed-dimensional Fermi surfaces consisting of quasi-one-dimensional hole sheet with out-of-plane velocity and quasi-two-dimensional electron sheets with in-plane velocity...

Solar-light photosynthesis of ammonia form N2 reduction in ultrapure water over the artificial photocatalysts is attractive but still challenging compared with Haber-Bosch process. In this work, ultrathin Fe-Ta2 O5-x nanobelts were fabricated via the controllable solvothermal process for ammonia photosynthesis. The formed oxygen vacancies and Fe doping narrowed their bandgap energies and promoted the carriers' separation and transfer for Fe-Ta2 O5-x nanobelts. In addition, Fe doping also resulted in the reduced working functions of the samples, indicating a weaker electron binding restriction and stronger separation and transfer of photo-induced carriers...

This article investigates the performance of a contact-mode Triboelectric Nanogenerator (TENG) utilizing polydimethylsiloxane (PDMS) with nano gratings as a dielectric in a metal-dielectric configuration. The evaluation encompasses the impact of gratings, tapping frequency, various load conditions, and contact area on the TENG performance. The fabrication involves spin-coating PDMS onto a master mold to create the device. Experimental measurements reveal a significant enhancement of 97% in open-circuit voltage by introducing gratings on PDMS...

Achieving selective transport of monovalent metal ions with high precision and permeability analogues to biological protein ion channels has long been explored for fundamental research and various applications, such as ion sieving, mineral extraction, and energy harvesting and conversion. However, it still remains a significant challenge to construct artificial nanofluidic devices to realize the trade-off effects between selective ion transportation and high ion permeability. In this work, we report a bioinspired functional micropipet with in situ growth of crown ether-encapsulated metal-organic frameworks (MOFs) inside the tip and realize selective transport of monovalent metal ions...

Natural photoactive systems have evolved to harness broad-spectrum light from solar radiation for critical functions such as light perception and photosynthetic energy conversion. Molecular photoswitches, which undergo structural changes upon light absorption, are artificial photoactive tools widely used for developing photoresponsive systems and converting light energy. However, photoswitches generally need to be activated by light of specific narrow wavelength ranges for effective photoconversion, which limits their ability to directly work under sunlight and to efficiently harvest solar energy...

The growing demand for wearable devices has sparked a significant interest in ferroelectret films. They possess flexibility and exceptional piezoelectric properties due to strong macroscopic-dipoles formed by charges trapped at the interface of their internal cavities. This review of ferroelectrets focuses on the latest progress in fabrication techniques for high temperature resistant ferroelectrets with regular and engineered cavities, strategies for optimizing their piezoelectric performance, and novel applications...

Recently, the non-covalently activated supramolecular scaffold method has become a prominent research area in the field of intelligent materials. Here, the inorganic clay (LP) promoted the AIE properties of 4,4',4″,4‴-(ethene-1,1,2,2-tetrayltetrakis(benzene-4,1-diyl))tetrakis(1-ethylpyridin-1-ium) (P-TPE), showing an astonishing 42-fold enhancement of the emission intensity of the yellow-green luminescence and a 34-fold increase of the quantum yield via organic-inorganic supramolecular strategy as well as the efficient light-harvesting properties (energy transfer efficiency up to 33 %) after doping with the dye receptor Rhodamine B...

The triboelectric nanogenerator (TENG) of natural biomaterials is a new type of energy harvesting device and can be used as a self-powered sensor, which has received extensive research and attention. In this paper, based on the biocompatibility of chitosan and chondroitin sulfate, ZnO-modified chitosan/chondroitin sulfate/ZnO TENG was prepared for research on wearable devices and sustainable power supply devices. This study employs molecular dynamics to compute the interaction energy between chitosan and ZnO molecules...

Water is readily available nearly anywhere as vapor. Thus, atmospheric water harvesting (AWH) technologies are seen as a promising solution to support sustainable water production. This work reports a novel semi-interpenetrating network, which integrates poly(pyrrole) doped with a hygroscopic salt and 2D graphene-based nanosheets optimally assembled within an alginate matrix, capable of harvesting water from the atmosphere with a record intake of up to 7.15 gw /gs . Owing to the incorporated graphene nanosheets, natural sunlight was solely used to enable desorption, achieving an increase of the temperature of the developed network of up to 71 °C within 20 min, resulting in a water yield of 3...

Environmental effects in excitation energy transfer have mostly been modeled by baths of harmonic oscillators, but to what extent such modeling provides a reliable description of actual interactions between molecular systems and environments remains an open issue. We address this issue by investigating fluctuations in the excitation energies of the light harvesting 2 complex using a realistic all-atomistic simulation of the potential energy surface. Our analyses reveal that molecular motions exhibit significant anharmonic features, even for underdamped intramolecular vibrations...

Converting dispersed mechanical energy into electrical energy can effectively improve the global energy shortage problem. The dispersed mechanical energy generated by liquid flow has a good application prospect as one of the most widely used renewable energy sources. Solid-liquid triboelectric nanogenerator (S-L TENG) is an inspiring device that can convert dispersed mechanical energy of liquids into electrical energy. In order to promote the design and applications of S-L TENG, it is of vital importance to understand the underlying mechanisms of energy conversion and electrical energy output affecters...