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Luminescent materials require systems that exhibit both dual‐state emission (DSE) and aggregation‐induced emission (AIE) to overcome the limitation of aggregation‐caused quenching (ACQ). Herein, a molecular assembler capable of crafting nanowires that exhibit programmable fluorescence across a broad spectrum of colors in a precisely quantized manner is reported. Because it is a starburst dendritic box made of PAMAM dendrimer (P), controller (C) molecules, and motor (M) molecules, the assembler is called PCM. Here, Nile red is chosen as C and placed into the hollow core of the dendrimer; a double ratchet motor (DRM) is chosen as M and is connected to the N‐terminals of the PAMAM dendrimer. While aqueous dispersed PCM assemblers have broad fluorescence bands beyond 300 nm, their crafted nanowires produce quantized cyan‐green, yellow, and orange‐red light emission in the spectra. These PCM assemblers are shown to hold long‐term memory, rapid switching, and energy harvesting by modulating photonic bandgaps, causing a longer redshift in the solid phase. The DSE of PCM can yield versatile photonics applications like bioimaging and energy harvesting. As PCM nanowires can modulate photonic bandgaps to cause a longer redshift, PCM fluorophores hold promise for drug delivery and cell separation like infrared‐sensitive operations. [ABSTRACT FROM AUTHOR]

Silk nanofibers (SNFs) from abundant sources are low‐cost and environmentally friendly. Combined with other functional materials, SNFs can help create bioelectronics with excellent biocompatibility without environmental concerns. However, it is still challenging to construct an SNF‐based composite with high conductivity, flexibility, and mechanical strength for all SNF‐based electronics. Herein, this work reports the design and fabrication of Ti3C2Tx‐silver@silk nanofibers (Ti3C2Tx‐Ag@SNF) composites with multi‐dimensional heterogeneous conductive networks using combined in situ growth and vacuum filtration methods. The ultrahigh electrical conductivity of Ti3C2Tx‐Ag@SNF composites (142959 S m−1) provides the kirigami‐patterned soft heaters with a rapid heating rate of 87 °C s−1. The multi‐dimensional heterogeneous network further allows the creation of electromagnetic interference shielding devices with an exceptionally high specific shielding effectiveness of 10,088 dB cm−1. Besides working as a triboelectric layer to harvest the mechanical energy and recognize the hand gesture, the Ti3C2Tx‐Ag@SNF composites can also be combined with an ionic layer to result in a capacitive pressure sensor with a high sensitivity of 410 kPa−1 in a large range due to electronic‐double layer effect. The applications of the Ti3C2Tx‐Ag@SNF composites in recognizing human gestures and human‐machine interfaces to wirelessly control a trolley demonstrate the future development of all SNF‐based electronics. [ABSTRACT FROM AUTHOR]

Hybrid nanogenerators are advanced mechanical energy harvesters capable of simultaneously scavenging multiple types of energy. Additionally, thermochromic materials provide a practical and visually assessable method for real‐time temperature monitoring. In this report, a novel energy harvester and sensing patch (EHSP) is introduced, that utilizes combined piezoelectric and triboelectric effects to harvest mechanical energy efficiently. To optimize the EHSP, various energy harvester configurations are fabricated and tested, and the dielectric properties of triboelectric films are systematically investigated. These improvements are implemented to augment the overall energy harvesting capability. The thermochromic properties of the EHSP are also explored to enhance both the electrical performance and thermal responsiveness. The EHSP demonstrates the ability to generate maximum voltage and current outputs of 350 V and 20.4 µA, respectively. Moreover, it can detect temperature changes within seconds, making it suitable for both energy harvesting and sensing applications. The EHSP is tested in practical scenarios, proving its efficiency as an energy harvester and sensor for everyday human activities. Furthermore, its integration with multiple hybrid nanogenerators showcases its potential for industrial and wearable sensing applications. [ABSTRACT FROM AUTHOR]

Herein, we present a novel method for fabricating a triboelectric nanogenerator using Polyacrylonitrile (PAN) on both sides as triboelectric pairs, incorporating metal‐organic frameworks (MOFs) such as ZIF‐8, ZIF‐67, MIL‐100, and HKUST‐1 during the electrospinning process. The triboelectric properties of the MOF‐incorporated fibers are thus tailored and positioned within the triboelectric series for the first time. The resulting triboelectric polarity of the composite fiber is linked to the optical bandgap energy of the PAN and the MOF/PAN composite, facilitating electron transfer between materials of different work functions and leading to enhanced output in the developed triboelectric devices. Fascinatingly, the appropriate choice of MOF filler also displayed the potential for reversing the triboelectric polarity of PAN nanofiber. Consequently, incorporating ZIF‐8 and MIL‐100 into PAN nanofibers led notably to contrasting trends in triboelectric polarity, with the pair generating an open‐circuit output voltage of 100 V, short‐circuit current of 1.35 μA, and a power density of 18.4 mW/m2 respectively. The fabricated device demonstrated effectiveness for mechanical energy harvesting applications and also as a self‐powered humidity sensor, displaying rapid response to changes in ambient humidity levels with a maximum sensitivity of 2.14 V/%RH, for relative humidity range between 50 and 90% during the humidifying cycle. [ABSTRACT FROM AUTHOR]

Gel‐based ionic thermoelectric (i‐TE) cells provide alternative thermal energy harvesting from the environment, showing obvious advantages in voltage matching for self‐powered Internet‐of‐Things (IoT) sensors. However, the gel‐based i‐TE cells always suffer a long thermal charging time and poor output power performance. Herein, a multilayer electrode engineering strategy is proposed from the device‐design level, aiming to decrease the ions' diffusion distance, increase the electrode surface area, and facilitate the ions' reaction and recovery process. The thermal charging time is shortened from 27 to 8 min as the electrode layers increase from 2 to 8. An ultrahigh instantaneous power density of 15.8 mW m−2 K−2 and 2 h output energy density (E2h) of 403 J m−2 are achieved in an 8‐layer electrode i‐TE cell. Finally, A flexible and wearable i‐TE device with 20 units is demonstrated to generate a remarkable voltage of 3.8 V and output power of 282 µW by harvesting the human body heat. This work provides a feasible and effective route to design the i‐TE device, hopefully promoting its practical power generation application. [ABSTRACT FROM AUTHOR]

The combination of microbial CO 2 reduction process and photocatalysis can meet the economic goal of sustainable carbon neutrality. Solar-energy as driven force can be achieved, by mimicking natural photosynthesis through the interaction between photo-responsive semiconductor nano-materials and electroautotrophic bacteria (EAB). Therefore, we reviewed the engineering strategies developed in recent years for photocatalytic microbial fixation of CO 2 to improve extracellular electron transfer (EET) rate and enhance the conversion efficiency of solar-to-chemical energy, including (1) the application principles of semiconductor nanomaterials in microbial CO 2 reduction systems; (2) photocathode; (3) photoanode; (4) dual photoelectrodes and (5) inorganic-microbe hybrid system; (6) perspectives on future challenges and opportunities for photocatalytic microbial fixation of CO 2 for sustainable energy and chemical production. This review will provide a theoretical basis for the future development of photocatalytic microbial fixation of CO 2 in energy harvesting, CO 2 fixation, and chemical synthesis. [ABSTRACT FROM AUTHOR]

This work aims to provide the hardware (HW) design of the optoelectronics interfaces for a visible-light communication (VLC) system that can be employed for several use cases. Potential applications include the transmission of ultra-high-definition (UHD) streaming video through existing reading lamps installed in passenger vans. In this use case, visible light is employed for the downlink, while infrared light is used for the uplink channel, acting as a remote controller. Two primary components -a Light Fidelity (LiFi) router and a USB dongle—were designed and implemented. The 'LiFi Router', handling the downlink channel, comprises components such as a visible Light-Emitting Diode (LED) and an infrared receiver. Operating at a supply voltage of 12 V and consuming current at 920 mA, it is compatible with standard voltage buses found in transport vehicles. The 'USB dongle', responsible for the uplink, incorporates an infrared LED and a receiver optimized for visible light. The USB dongle works at a supply voltage of 5 V and shows a current consumption of 1.12 A, making it well suited for direct connection to a universal serial bus (USB) port. The bandwidth achieved for the downlink is 11.66 MHz, while the uplink's bandwidth is 12.27 MHz. A system competent at streaming UHD video with the feature of being single-input multiple-output (SIMO) was successfully implemented via the custom hardware design of the optical transceivers and optoelectronics interfaces. To ensure the system's correct performance at a distance of 110 cm, the minimum signal-to-noise ratio (SNRmin) for both optical links was maintained at 10.74 dB. We conducted a proof-of-concept test of the VLC system in a passenger van and verified its optimal operation, effectively illustrating its performance in a real operating environment. Exemplifying potential implementations possible with the hardware system designed in this work, a bit rate of 15.2 Mbps was reached with On–Off Keying (OOK), and 11.25 Mbps was obtained with Quadrature Phase Shift Keying (QPSK) using Orthogonal Frequency-Division Multiplexing (OFDM) obtaining a bit-error rate (BER) of 3.3259 × 10−5 in a passenger van at a distance of 72.5 cm between the LiFi router and the USB dongle. As a final addition, a solar panel was installed on the passenger van's roof to power the user's laptop and the USB dongle via a power bank battery. It took 13.4 h to charge the battery, yielding a battery life of 22.3 h. This characteristic renders the user's side of the system entirely self-powered. [ABSTRACT FROM AUTHOR]

Underwater acoustic sensor networks (UASNs) are fundamental assets to enable discovery and utilization of sub-sea environments and have attracted both academia and industry to execute long-term underwater missions. Given the heightened significance of battery dependency in underwater wireless sensor networks, our objective is to maximize the amount of harvested energy underwater by adopting the TDMA time slot scheduling approach to prolong the operational lifetime of the sensors. In this study, we considered the spatial uncertainty of underwater ambient resources to improve the utilization of available energy and examine a stochastic model for piezoelectric energy harvesting. Considering a realistic channel and environment condition, a novel multi-agent reinforcement learning algorithm is proposed. Nodes observe and learn from their choice of transmission slots based on the available energy in the underwater medium and autonomously adapt their communication slots to their energy harvesting conditions instead of relying on the cluster head. In the numerical results, we present the impact of piezoelectric energy harvesting and harvesting awareness on three lifetime metrics. We observe that energy harvesting contributes to 4% improvement in first node dead (FND), 14% improvement in half node dead (HND), and 22% improvement in last node dead (LND). Additionally, the harvesting-aware TDMA-RL method further increases HND by 17% and LND by 38%. Our results show that the proposed method improves in-cluster communication time interval utilization and outperforms traditional time slot allocation methods in terms of throughput and energy harvesting efficiency. [ABSTRACT FROM AUTHOR]

This paper presents innovations in green electronic and computing technologies. The importance and the status of the main subjects in green electronic and computing technologies are presented in this paper. In the last semicentennial, the planet suffered from rapid changes in climate. The planet is suffering from increasingly wild storms, hurricanes, typhoons, hard droughts, increases in seawater height, floods, seawater acidification, decreases in groundwater reserves, and increases in global temperatures. These climate changes may be irreversible if companies, organizations, governments, and individuals do not act daily and rapidly to save the planet. Unfortunately, the continuous growth in the number of computing devices, cellular devices, smartphones, and other smart devices over the last fifty years has resulted in a rapid increase in climate change. It is severely crucial to design energy-efficient "green" technologies and devices. Toxic waste from computing and cellular devices is rapidly filling up landfills and increasing air and water pollution. This electronic waste contains hazardous and toxic materials that pollute the environment and affect our health. Green computing and electronic engineering are employed to address this climate disaster. The development of green materials, green energy, waste, and recycling are the major objectives in innovation and research in green computing and electronics technologies. Energy-harvesting technologies can be used to produce and store green energy. Wearable active sensors and metamaterial antennas with circular split ring resonators (CSSRs) containing energy-harvesting units are presented in this paper. The measured bandwidth of the matched sensor is around 65% for VSWR, which is better than 3:1. The sensor gain is 14.1 dB at 2.62 GHz. A wideband 0.4 GHz to 6.4 GHz slot antenna with an RF energy-harvesting unit is presented in this paper. The Skyworks Schottky diode, SMS-7630, was used as the rectifier diode in the harvesting unit. If we transmit 20 dBm of RF power from a transmitting antenna that is located 0.2 m from the harvesting slot antenna at 2.4 GHz, the output voltage at the output port of the harvesting unit will be around 1 V. The power conversion efficiency of the metamaterial antenna dipole with metallic strips is around 75%. Wearable sensors with energy-harvesting units provide efficient, low-cost healthcare services that contribute to a green environment and minimize energy consumption. The measurement process and setups of wearable sensors are presented in this paper. [ABSTRACT FROM AUTHOR]

This article introduces a novel regenerative suspension system designed for active seat suspension, to reduce vibrations while recovering energy. The system employs a four-quadrant electric actuator operation model and utilizes a brushless DC motor as an actuator and an energy harvester. This motor, a permanent magnet synchronous type, transforms DC into three-phase AC power, serving dual purposes of vibration energy recovery and active power generation. The system's advanced vibration control is achieved through the switching of MOSFET transistors, ensuring the suspension system meets operational criteria that contrast with traditional vibro-isolation systems, thereby reducing the negative effects of mechanical vibrations on the human body, while also lowering energy consumption. Comparative studies of the regenerative system dynamics against passive and active systems under random vibrations demonstrated its effectiveness. This research assessed the system's performance through power spectral density and transmissibility functions, highlighting its potential to enhance energy efficiency and the psychophysical well-being of individuals subjected to mechanical vibrations. The effectiveness of the energy regeneration process under the chosen early excitation vibrations was investigated. Measurements of the motor torque in the active mode and during regenerative braking mode, and the corresponding phase currents of the motor, are presented. [ABSTRACT FROM AUTHOR]

Over the past decade, various researchers have shown the practicality of extracting electrical energy from vibrating structures. The primary objective of this research was to optimize the parameters of a basic cantilever harvester to maximize the energy production of electricity from surrounding mechanical energy. A distributed parameter model and its modal solution were utilized to determine the design variables via a parametric investigation. It is important to ensure sufficient power generation when there is a wide range of frequencies being excited, without any specific frequency being emphasized. The cost function for the optimization problem was defined as the average power within a specific frequency range, considering geometric and physical restrictions. It was discovered that different parameters' values can be utilized to generate varying maximum power levels for different frequency ranges. Furthermore, a comparative analysis was performed between the finite element method (FEM) using ANSYS and the current harvesting model. The comparison demonstrated a high level of concordance, enabling the utilization of the finite element method (FEM) for subsequent investigation. [ABSTRACT FROM AUTHOR]

The widespread use of single-use face masks during the recent epidemic has led to significant environmental challenges due to waste pollution. This study explores an innovative approach to address this issue by repurposing discarded face masks for hydrovoltaic energy harvesting. By coating the face masks with carbon black (CB) to enhance their hydrophilic properties, we developed mask-based hydrovoltaic power generators (MHPGs). These MHPGs were evaluated for their hydrovoltaic performance, revealing that different mask configurations and sizes affect their efficiency. The study found that MHPGs with smaller, more structured areas exhibited better energy output, with maximum open-circuit voltages (VOC) reaching up to 0.39 V and short-circuit currents (ISC) up to 65.6 μA. The integration of CB improved water absorption and transport, enhancing the hydrovoltaic performance. More specifically, MHPG-1 to MHPG-4, which represented different sizes and features, presented mean VOC values of 0.32, 0.17, 0.19 and 0.05 V, as well as mean ISC values of 16.57, 15.59, 47.43 and 3.02 μA, respectively. The findings highlight the feasibility of utilizing discarded masks in energy harvesting systems, offering both environmental benefits and a novel method for renewable energy generation. Therefore, this work provides a new paradigm for waste-to-energy (WTE) technologies and inspires further research into the use of unconventional waste materials for energy production. [ABSTRACT FROM AUTHOR]

This research aims to use energy harvested from conductive materials to power microelectronic components. The proposed method involves using vibration-based energy harvesting to increase the natural vibration frequency, reduce the need for battery replacement, and minimise chemical waste. Piezoelectric transduction, known for its high-power density and ease of application, has garnered significant attention. Additionally, graphene, a non-piezoelectric material, exhibits good piezoelectric properties. The research explores a novel method of printing graphene material using 3D printing, specifically Direct Ink Writing (DIW) and fused deposition modelling (FDM). Both simulation and experimental techniques were used to analyse energy harvesting. The experimental technique involved using the cantilever beam-based vibration energy harvesting method. The results showed that the DIW-derived 3D-printed prototype achieved a peak power output of 12.2 µW, surpassing the 6.4 µW output of the FDM-derived 3D-printed prototype. Furthermore, the simulation using COMSOL Multiphysics yielded a harvested output of 0.69 µV. [ABSTRACT FROM AUTHOR]

[Display omitted] Two-dimensional (2D) transition metal carbides/nitrides, MXenes (in particular Ti 3 C 2 T x), and three-dimensional (3D) structures such as polymeric hydrogels or aerogels, are promising families of materials, each in their own right, with advantageous properties for applications in biomedicine, water treatment, electronic devices, and energy. Combination of MXenes with hydro- or aerogels may further improve their individual properties and impart new characteristics. Potentially, it can also significantly improve the chemical stability of MXenes, which is currently one of the main limiting factors for their widespread use. In this paper, we review some representative fabrication techniques and properties of Ti 3 C 2 T x MXene/3D hydrogel and aerogel composites, as well as selected applications of these composites for energy storage and harvesting, biology and medicine, water treatment, and EMI shielding. [ABSTRACT FROM AUTHOR]

Real-time onboard health monitoring systems are critical for the railway industry to maintain high service quality and operational safety. However, the issue with power supplies for monitoring sensors persists, especially for freight trains that lack onboard power. Here, we propose a hybrid piezoelectric-triboelectric rotary generator (HPT-RG) for energy harvesting and vehicle speed sensing. The HPT-RG incorporates a rotational self-adaptive technique that softens the equivalent stiffness, enabling the piezoelectric non-resonant beam to surpass resonance limitations in a low-frequency region. The experiments demonstrate the feasibility of using the HPT-RG as an energy harvesting module to collect the rotational energy of the freight rail transport and power the wireless temperature sensors. To allow multiple monitoring in confined spaces on trains, a triboelectric sensing module is added to the HPT-RG to sense the operation speed and mileage of vehicles. Furthermore, the generator exhibits favorable mechanical durability under more than 600 h of official testing on the train bogie axle. The proposed HPT-RG is essential for creating a truly self-powered, maintenance-free, and zero-carbon onboard wireless monitoring system on freight railways. [ABSTRACT FROM AUTHOR]

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. Furthermore, as the tapping frequency increases from 1 Hz to 3 Hz, there is a corresponding rise of 108% in output voltage. The influence of load resistance on TENG output performance demonstrates its ability to drive different loads efficiently. Moreover, enlarging the contact area of the device substantially increases the open-circuit voltage. A device with a 400 mm2 contact area can generate a voltage of 80 V at a low frequency of 3 Hz, indicating the importance of considering device size and contact area for specific applications. A practical circuit integrating a TENG with a full-wave bridge rectifier demonstrates energy harvesting capabilities by successfully illuminating a light-emitting diode (LED) and charging various capacitors. The fabricated devices exhibit better performance along with a cost-effective and easy fabrication process. [ABSTRACT FROM AUTHOR]

[Display omitted] 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. Theoretical calculations have unequivocally substantiated the occurrence of a binding interaction between these two molecular entities. The effect of ZnO on chitosan/chondroitin sulfate morphology was investigated by atomic force microscopy. The chitosan/chondroitin sulfate/ZnO TENG has high flexibility and electrical output performance. It can reach 105 V and 3.3 µA of open-circuit voltage and short-circuit current. Chitosan/chondroitin Sulfate/ZnO TENG successfully converts the mechanical energy of human motion into electrical energy. Strong electrical signals are exhibited when making fists and waving fingers and wrists. The TENG is a self-powered source and lights up 70 blue light-emitting diodes (LEDs). The chitosan/chondroitin sulfate/ZnO TENG has demonstrated its capabilities in energy harvesting and wearable self-powered sensors. [ABSTRACT FROM AUTHOR]

The harnessing and utilization of mechanical energy through frictional route have emerged as a promising avenue for advancing clean energy initiatives. Triboelectric charges are generated on the surface of two different materials during friction. These charges are similar to photocatalytic charges and can be utilized for dye degradation by a process called tribocatalysis. In this study, it was found that lithium borate bismuth tungstate (0.7 L i 2 B 4 O 7 − 0.3 B i 2 W O 6) nanocrystal glass-ceramics synthesized by melt-quench technique exhibit excellent tribocatalytic dye degradation performance by harvesting friction energy. X-ray diffraction technique, Raman Spectroscopy and Transmission Electron Microscopy (TEM) was performed to examine the structure, phase, and microstructure of the prepared samples. The maximum tribocatalytic decomposition of Methylene Blue (MB) dye observed was 56 % for as-quenched sample (AQ) and 74 % for heat-treated sample (HT) after 10 h of mechanical stirring at 700 rpm and for Rhodamine B (RhB) dye the degradation achieved was 34 % and 64 % in 8 h for AQ and HT respectively. Due to their superior dye decomposition capabilities, glass-ceramic crystals hold significant promise for harnessing mechanical energy through friction in wastewater treatment processes. [ABSTRACT FROM AUTHOR]

As worries about climate change and energy security grow, the need for clean and sustainable energy sources becomes increasingly critical. Among the possible alternatives, solar thermal technology provides a dependable and adaptable method for harnessing the sun's energy as heat. At the core of this technique is the solar thermal absorber, a critical component that converts sunlight into useful thermal energy. The Graphene Based Disk-Square Integration Resonator Solar Absorber (GBDSIRSA) structure is examined in this work between 200 and 2500 nm in wavelength. The GBDSIRSA has remarkable performance throughout a wide variety of spectral ranges, underscoring its adaptability and effectiveness. GBDSIRSA has exceptional efficiency in absorbing light over the full spectrum, from UV to MIR wavelengths, with an average absorptance of 97.73%. The absorptance rates are particularly high, achieving 94.02% in the UV, 96.36% in the VIS, 97.12% in the NIR, and an astounding 98.94% in the mid-infrared (MIR) region. The GBDSIRSA is independent of polarization effect and also an incident angle independent up to 80 degrees. The machine learning (Local Regression) approach used with test size of 0.2 and 1.8780 ×10-5 mean squared error for absorptance prediction has good prediction accuracy R2 of more than 95% which is applied to simulation resource reduction. Because of its wide absorptance spectrum, polarization and incident angle independence, the GBDSIRSA is a very promising technology for a variety of applications, including thermal imaging and renewable energy. It can efficiently harvest solar energy. All things considered, GBDSIRSA's remarkable absorptance properties highlight its promise as a top choice for cutting-edge optical and solar energy applications. [ABSTRACT FROM AUTHOR]

This research aims to optimize piezoelectric implants for orthopedic applications, enhancing energy harvesting efficiency and mechanical integrity. Our objectives include comparing piezoelectric materials (PZT, PVDF, and BaTiO3) and employing advanced theoretical modeling, finite element analysis (FEA), and validation to identify optimal configurations. Methodologically, this study integrates machine learning and AI-driven techniques to refine design parameters and predict performance outcomes. Significant findings have revealed that PZT demonstrated the highest sensitivity (2 V/mm), achieving a maximum power output of 4.10 Watts, surpassing traditional solutions by over 100%. The optimization process ensured uniform stress distribution, reducing mechanical failure risk, with predictive models showing high accuracy (R-squared value of 97.77%). Error analysis indicated minimal discrepancies, with an average error margin of less than 2%. The conclusions highlight the significant potential of optimized piezoelectric implants in developing durable, efficient, and patient-friendly orthopedic solutions, setting a new standard in intelligent medical device innovation and contributing to enhanced patient care and improved clinical outcomes. [ABSTRACT FROM AUTHOR]

Several photovoltaic technologies, based on different semiconductor absorbers with band-gap energy in the range Eg = 1.0–1.5 eV are currently sharing the market for outdoor applications. These photovoltaic cells are designed to achieve an optimal photovoltaic conversion under solar illumination (represented by the standard AM1.5 global spectrum), but their performance changes under different artificial indoor lights. Here, the detailed balance principle that was first applied for an ideal photovoltaic absorber under solar radiation is now used by considering the actual spectra of four typical indoor lamps: incandescent, halogen, metal halide and white LED. For each particular illumination source, the theoretical maximum for short-circuit current, open-circuit voltage and maximum power point have been calculated and represented as a function of the absorber band-gap energy. Furthermore, the optical absorption spectra of some semiconductors with optimal solar conversion efficiencies are used to estimate their comparative performance under the various artificial light sources. It has been found that wide band-gap absorbers (Eg~1.9 eV) are needed to achieve a light-to-electricity conversion efficiency of 60% under LED illumination or 31% with metal halide bulbs, while a lowest band-gap energy of about 0.8 eV is required to obtain a maximum efficiency of 24% with incandescent and halogen lamps. [ABSTRACT FROM AUTHOR]

Copyright of Micronanoelectronic Technology is the property of Micronanoelectronic Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Piezo‐photocatalysis could coalesce the advantages of mechanical vibration and solar energy perfectly to achieve high‐efficiency catalytic activity. Herein, the quintessential piezoelectric material CdS nanowires with different aspect ratios are precisely constructed and applied for piezo‐photocatalytic reduction of U(VI) for the first time. The ultrasonic (60 kHz, 100 W) induces piezoelectric potential to generate a 0.57 eV A−1 electric field, which is added to the direction of CdS (010) as a driving force to efficiently separate photogenerated charges. The alliance between piezoelectric effect and photocatalytic activity endows CdS NW‐3 with the fastest piezo‐photocatalytic rate under ultrasonic vibration and 5 W LED irradiation, and the relevant rate constant (0.042 min−1) is about 12 and 53.8 times than that of LED and ultrasonication. More importantly, 93.74% of U(VI) could be removed from natural uranium mine wastewater. Therefore, this piezo‐photocatalysis system that reduces U(VI) to easily separable (UO2)O2·2H2O(s) provides valuable input for disposal applications of radioactive wastewater and broadens the horizons of nuclear energy utilization toward the advancement of carbon neutrality. [ABSTRACT FROM AUTHOR]

Wearable triboelectric nanogenerators (TENGs) have attracted attention owing to their ability to harvest energy from the surrounding environment without maintenance. Herein, polyetherimide–Al2O3 (PAl) and polyvinylidene fluoride‐co‐hexafluoropropylene (PVDF‐HFP, PH) nanofiber membranes were used as tribo‐positive and tribo‐negative materials, respectively. Phytic acid‐doped polyaniline (PANI)/cotton fabric (PPCF) and ethylenediamine (EDA)‐crosslinked PAl (EPAl) nanofiber membranes were used as triboelectrode and triboencapsulation materials, respectively. The result showed that when the PAl–PH‐based TENG was shaped as a circle with a radius of 1 cm, under the pressure of 50 N, and the frequency of 0.5 Hz, the open‐circuit voltage (Voc) and short‐circuit current (Isc) reached the highest value of 66.6 V and −93.4 to 110.1 nA, respectively. Moreover, the PH‐based TENG could be used as a fabric sensor to detect fabric composition and as a sensor‐inductive switch for light bulbs or beeping warning devices. When the PAl–PH‐based TENG was shaped as a 5 × 5 cm2 rectangle, a 33 μF capacitor could be charged to 15 V in 28 s. Interestingly, compared to PAl nanofiber membranes, EPAl nanofiber membranes exhibited good dyeing properties and excellent solvent resistance. The PPCF exhibited <5% resistance change after washing, bending, and stretching. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Triboelectric nanogenerators (TENGs) have emerged as a promising technology to harvest electrical energy from natural motions such as human movement, wind, and water flow. Although TENGs show significant potential in small-scale applications, developing large-scale TENGs capable of generating high power remains a significant challenge. Several factors that can affect the performance of large-scale TENGs are being investigated to overcome this challenge, including the size and configuration of dielectric materials. This study optimizes dielectrics regarding surface area, thickness, and multicell configuration to improve harvested electrical power density in large-scale TENGs. In the studies, glass fiber was used as the positive dielectric, and multipurpose white silicone was used as the negative dielectric because of their high tribo-potential, durability, and easy accessibility. In the size optimization phase, dielectric thicknesses and surface areas that provide the maximum power density were determined. Subsequently, horizontal and vertical multicell configurations were examined to efficiently integrate size-optimized dielectrics. The results reveal that large-scale TENGs with vertical multicell configurations can achieve high and usable energy density for electronics. The findings provide valuable insight into the development of large-scale TENGs with advanced power generation capabilities. [ABSTRACT FROM AUTHOR]

Hydroponic farming is a promising alternative to soil-based farming. However, it requires a precise control of the growth environment, which is hard to achieve with energy-constrained embedded systems. This letter presents an energy optimization technique for the continuous operation of energy harvesting-based hydroponics sensor nodes. The proposed technique is based on the self-tuning model, that dynamically adjust the duty cycle of the node, ensuring the autonomous operation of the Internet of Things system. The model can be programmed in a low-power microcontroller, allowing the decision-making process to reside entirely on the sensor node. Experimental results show that in the same time period, the self-tuning model allows $3.5\times $ more data transmissions than a uniform 5-min duty cycle, while ensuring a minimum voltage level in the storage device. This balance allows the stored energy to be enough for continuous monitoring, providing a clean and cost-effective alternative to perpetually power the hydroponic system. [ABSTRACT FROM AUTHOR]

The displacement of air masses caused by the movement of objects or vehicles is often characterized by considerable energy content, which, with appropriate technologies, can be partially recovered. In this sense, numerous scientific works consider rail transport as a possible context for application. However, the literature in the sector highlights how using existing wind technologies in these areas involves many difficulties, mainly related to the turbulent and impulsive nature of the airflows generated. This work presents the architecture and general aspects of an innovative technology for obtaining electrical energy from variable and impulsive airflows, such as those due to the rapid transit of railway trains in tunnels, without precluding its use in other similar fields. The innovative aspect mainly concerns the independent control of two distinct typologies of bladed elements, which can also have translational movement and drag-based and lift-based aerodynamic behavior to improve the adaptability of the embodiment to the site's fluid dynamic and geometric characteristics. Furthermore, the structural simplification of the apparatus, shifting some of the technological complexity to the control systems, brings further advantages in terms of construction cost, robustness, maintenance, reuse, and transferability to different contexts. Of course, the counterpart of these benefits lies in the software and hardware of the control devices. Analytical models to determine the non-dimensional performance coefficients of the two basic types have been reported as has the architectural model of the control system. The technology shown in this work is protected by an EP and US Patent. [ABSTRACT FROM AUTHOR]

The intricacies of relay-aided device-to-device (D2D) communication within the novel fluctuating two-ray (FTR) model is inspected in this study. Two cases with respect to co-channel interference are considered here, in case A, co-channel interferences due to unmanned aerial vehicles affect the relay while at the D2D receiver, the co-channel interferences follow the FTR model. In case B, interferences due to unmanned aerial vehicles affect the D2D receiver and the relay now experiences interferences over the FTR channels. The channel of a co-channel interference due to unmanned aerial vehicle is assumed to be a recently proposed single-shadowing based composite fading model. Further enhancing operational efficiency, the D2D receiver incorporates a power splitting mechanism for power harvesting. In this analysis a characteristic function-based approach is applied, which serves as the foundational cornerstone for deriving expressions that govern the outage and success probabilities. These intricate expressions are connected with critical factors, such as the dynamics of path-loss phenomena, the spatial separation between the interferers and the relay, the varying distances between the interferers and the D2D receiver, and the physical gap bridging the relay and the D2D receiver. Building upon the derived expressions, an extensive numerical analysis unfurls them for both interference cases. [ABSTRACT FROM AUTHOR]

Research conducted around the world shows that energy harvesting (EH) systems can be used in contemporary vehicles powered by combustion engines, hybrid or electric motors. Unfortunately, the efficiency of modern combustion engines is only about 40%, the remaining energy is lost and can be recovered to some extent. Therefore, the search is ongoing for systems that will use this part of the energy to power specific systems or micro-sensors installed in the vehicle. The article presents the possibilities of energy harvesting from four main sources in the vehicle: energy during braking, energy from the damping of the vehicle suspension, from the exhaust system and energy from the vibrations of the combustion engine. Based on the analysis of the literature on the presented research of various scientific centres and the author's experiment, it can be concluded that there is a huge potential for obtaining thermal energy from the engine exhaust system and the vehicle suspension system. A field that has not been explored much, but according to the authors also has energy potential, is the recovery of energy generated during vibrations in the suspension of an internal combustion engine in the engine compartment of the vehicle. For the obtained measurement data from the experiments, initial digital processing of the signal was performed using a low-pass filter, then the fast fourier transform (FFT) and the Hilbert-Huang Transformation (HHT) were used. Preliminary research shows the possibility of mounting the energy recovery system in the engine compartment and the potential possibility of obtaining electricity in certain operating states of the combustion engine. [ABSTRACT FROM AUTHOR]

Non-orthogonal multiple access (NOMA) enables the concurrent transmission of numerous user signals, ameliorating spectral efficiency by superimposing these signals. NOMA users utilize energy harvesting to efficiently utilize available energy sources. The energy harvesting process is non-linear in general. Additionally, innumerable antennas are used at the NOMA transmitter and power source to facilitate efficient energy transfer and information transmission with antenna selection (AS). Also, wireless channels cause path loss, fading, and shadowing effects, which directly influence harvested energy and communication reliability. Accordingly, the work assesses the outage performance and throughput of NOMA, examining realistic aspects like non-linear energy harvesting (nlEH), AS, multiple antennas, and κ - μ shadowed fading. The findings indicate a considerable performance degradation due to nlEH. Moreover, appropriate parameter selection is crucial for preventing complete outages in NOMA networks and achieving optimal performance. In addition, the performance of NOMA networks meliorates with an accreting number of antennas. Furthermore, the AS criterion dramatically impacts performance difference between NOMA users. [ABSTRACT FROM AUTHOR]

To alleviate resource shortage and environmental pollution, solar energy can be converted into thermal energy stored in phase change materials and in turn generate electrical energy. To enhance the solar energy utilization efficiency of solar‐thermal‐electrical conversion devices and prevent the heat loss to the environment at night, an intelligent solar‐responsive phase‐change system is innovatively designed consisting of a graphene aerogel film/paraffin wax stamen with an ultra‐high thermal conductivity of 46.7 W m−1 K−1, and thermally preserving aerogel film/liquid crystal elastomer bilayer petals that can bend solar‐responsively by the synergistic effect of solar‐thermal energy conversion and heat‐induced contraction. The solar‐responsive phase‐change system achieves daytime blooming for solar‐thermal conversion with simultaneous energy storage and nighttime closing for minimizing heat loss to the environment, exhibiting a high solar‐thermal conversion and energy storage efficiency of 89.4% and delaying its temperature drop by the thermal preservation effect of the petals. The assembled solar‐responsive solar‐thermal‐electric generator can reach an output voltage of 1033.8 mV at a light intensity of 500 mW cm−2 and continue to generate electrical energy during nighttime, holding tremendous promise in efficient solar energy conversion, storage, and utilization. [ABSTRACT FROM AUTHOR]

Drawing inspiration from nature has served as a crucial driving force behind human progress, enabling groundbreaking advancements and cross‐disciplinary integration through the emulation of biological superhydrophobic phenomena. Bioinspired superhydrophobic triboelectric materials stand out among advanced triboelectric materials due to their unique hydrophobic properties, exceptional moisture resistance, and remarkable electrical performance. However, the inherent complexity of natural phenomena and the need for refinement in bioinspired design pose significant challenges in the development of bioinspired superhydrophobic triboelectric materials. This comprehensive review delves into bioinspired superhydrophobic triboelectric materials from the perspectives of theoretical underpinnings, fabrication strategies, and cutting‐edge applications. Rooted in the interaction mechanisms between water molecules and triboelectric materials, the importance of enhanced hydrophobic properties is elucidated. A systematic overview of bioinspired superhydrophobic triboelectric materials’ construction strategies is presented, offering fresh perspectives and insights into the development and application of high‐performance triboelectric nanogenerators (TENGs). Finally, the current challenges and untapped opportunities in bioinspired superhydrophobic triboelectric materials are summarized to fully unlock their potential for applications in TENGs. [ABSTRACT FROM AUTHOR]

This perspective provides an overview of the state of research and innovation in the areas of magnetocaloric and pyromagnetic materials, and electrocaloric and pyroelectric materials, including the overlapping sub‐areas of multicaloric and multipyro materials that can operate simultaneously under the application of magnetic and electric fields. These materials are critically examined for their potential to revolutionize cooling, heating, and energy‐harvesting applications. This perspective first summarizes the state‐of‐the‐art advancements and highlights recent significant developments. Then, it is identified and discussed that the prevailing challenges hindering the widespread adoption of technologies based on these materials. In this context, after consulting with members of the caloric and pyro communities, a technology roadmap is outlined to guide research efforts in overcoming current barriers to applications, with the goal of achieving impactful results by 2040. This roadmap emphasizes the importance of focusing on under‐researched materials, novel devices, and application spaces, paving the way for interdisciplinary efforts that can lead to significant reductions in carbon dioxide emissions. [ABSTRACT FROM AUTHOR]

A piezoelectric‐electromagnetic composite energy harvester (PECEH) has been designed, to mainly study the relationship between the length and angle of piezoelectric cantilever beams and their power generation performance, and the analysis of dynamic models in magnetic levitation systems and the impact of magnet size on power generation performance. In this device, piezoelectric energy harvester (PEH) and electromagnetic harvester (EMH) are used as powered and sensing, respectively. The PEH collects vibration to generate electricity and supplies energy to the EMH, which then transmits the wireless signal. EMH adopts a magnetic levitation device with higher sensitivity, while PEH uses a direct contact strike piezoelectric plate to increase power generation. The paddles are made of flexible materials, which increase the durability of the device. The prototype was tested at different excitation frequencies. Research has shown that at a frequency of 1.4 Hz, the optimal voltage and power are 126.28, 4.04 V, and 4.9 mW and 0.57 μW. 60 light emitting diode can be lit when pedestrians are walking. Therefore, PECEH can be used to collect the vibration energy of pedestrians while walking, providing power to sensors and microstructure. [ABSTRACT FROM AUTHOR]

In the endeavor to mimic natural light‐harvesting systems (LHSs), a persistent challenge has been the tendency of synthetic materials to adopt spherical architectures rather than the desired multitubular structures found in nature. In this study, a novel carboxylbetaine‐type zwitterionic surfactant with aggregation‐induced emission (AIE) properties is designed. By coassembling with anionic surfactants, multiwalled tubules comprising bilayer membranes ≈5 nm thick are successfully constructed. With AIE fluorophores densely packed at the center, their AIE properties are triggered to serve as an efficient antenna for light harvesting and energy transfer. This facilitated high antenna effects via energy transfer from cyan fluorescent donor to yellow fluorescent acceptor and then to red fluorescent acceptor. Additionally, the emission color can be adjusted from blue to red by manipulating the donor/acceptor/acceptor ratio, with pure white‐light emission achievable at specific ratios. This achievement not only realizes the construction of efficient sequential LHSs but also offers inspiration for the future design of artificial multitubular systems. [ABSTRACT FROM AUTHOR]

Thermal rectification devices, which facilitate preferential heat flow in a singular direction, stands as pivotal tools in the realization of solid‐state thermal circuits. 1D atomic chains, exhibit heightened thermal rectification efficiency owing to their exceptional directional heat conduction properties. These will find widespread utility in many applications, encompassing areas such as cooling, energy harvesting, and thermal isolation systems. However, unlike quasi‐1D materials, the intrinsic anisotropic heat transport in true‐1D atomic chains is yet to be systematically studied. Herein, the origins of the anisotropic heat transfer in three representative 1D structures (TaSe3 and BaTiS3 marked as quasi‐1D, MoI3 labeled as true‐1D) is first investigated by integrating a first‐principles density functional theory‐based framework of two‐channel heat conduction model. In contrast to quasi‐1D, MoI3 exhibits a giant anisotropy of lattice thermal conductivity (κL) in chain‐ and cross chain‐directions with a high ratio up to ≈20, which far exceeds the previous report for HfTe5 and ZrTe5. Such unique heat transfer reveals comprehensively by charge‐sharing and transferred charges, p‐‐d orbital hybridization and Young's modulus changes, induces an exceptionally large anisotropy. This study presents a high‐performance implementation of thermal rectification designed to regulate directional heat current, demonstrating its potential applicability in solid‐state thermal circuits. [ABSTRACT FROM AUTHOR]

Deploying triboelectric nanogenerator (TENG) units on and below the water surface has been a conventional method for harvesting wave energy. However, this approach restricts the TENG's amplitude to that of the water waves, limiting the actual offshore output. Here, a new method of placing TENG units above the water surface using a wave amplitude amplifier is reported. This addresses the issue of insufficient amplitude in traditional wave energy TENGs and achieves higher electrical output performance in real offshore conditions. Moreover, the innovative four‐helix TENG (FH‐TENG), designed with special pattern cutting and bridging techniques, eliminates the need for internal wires, foundational frameworks, and counterweights. Results show that FH‐TENG placed on the amplitude amplifier achieves over a 76% increase in amplitude and a 235% enhancement in charge output compared to FH‐TENG floating directly on the water surface, and the maximum output voltage, transferred charge and output current reach 246 V, 7.9 µC, and 156.1 µA, respectively. Importantly, when deployed in real marine environments, this system generates more electric energy than in a lab pool under the same peak wave height, providing a reliable power supply solution. This work establishes a precedent for deploying lightweight wave energy TENGs above the water surface. [ABSTRACT FROM AUTHOR]

In today's era of increasing energy constraints, harnessing the power of electromagnetic waves and converting them into directly usable energy has great potential in the field of renewable energy. This paper presents a highly efficient electromagnetic energy harvester with wide operation angles based on metasurface. The metasurface unit comprises four rotated copper rings plated on a Rogers RT5880 substrate. This unique design incorporates a 3.6 kΩ resistor within each of the four-cornered rotating metal rings, effectively emulating the input impedance circuit of a rectifier. Simulation results reveal that the metasurface achieves a remarkable electromagnetic wave harvesting efficiency of up to 92.3% at a frequency of 5.85 GHz. Additionally, it exhibits polarization insensitivity, enhancing its versatility and suitability for wide incident angles, which augments its practicality in various environments. The proposed metasurface energy harvester represents a significant advancement in electromagnetic energy collection technology, offering an efficient and reliable energy harvesting solution that contributes to addressing energy shortages and is applicable across multiple scenarios. [ABSTRACT FROM AUTHOR]

AbstractIn ultralow-frequency and broadband environments, vibration energy harvesters exhibit lower energy harvesting efficiency. This article introduces a bistable vibration energy harvester that leverages a nonlinear spring oscillator to excite a Piezoelectric Energy Harvester (PEH), facilitating the efficient harvest of vibrational energy. We present the theoretical model, numerical analysis, and experimental validation for this system, featuring nonlinear springs and magnetic force to magnetically “pluck” the PEH, inducing superharmonic resonance. The results show that the PEH has complex dynamic phenomena such as intra-well superharmonic orbit, inter-well odd multiple superharmonic orbit, and chaos. The PEH demonstrates efficient energy harvesting capabilities near its natural resonance frequency of 12.66 Hz under low-amplitude (0.19–0.47 g) and ultralow-frequency (2.93–4.57 Hz) excitations. Remarkably, when the PEH's natural frequency aligns as triple of the excitation frequency, its vibrational energy significantly increases, highlighting its potential for optimal energy harvesting in environments characterized by low-amplitude and ultralow-frequency vibrations. [ABSTRACT FROM AUTHOR]

Sodium cobaltite (NaxCoO2) is one of the most renowned and thermoelectrically promising p‐type cobalt oxide materials, showing exceptional performance in this domain. Nonetheless, its thermal instability in air renders it unsuitable for high‐temperature applications such as energy harvesting from industrial waste heat. To utilize the beneficial properties of NaxCoO2, microscale NaxCoO2 template particles of significantly larger size were effectively embedded within a thermally stable Ca3Co4−yO9+δ–NaxCoO2–Bi2Ca2Co2O9 triple‐phase matrix. This approach additionally aimed to enhance the texture and boost the thermoelectric performance of the ceramic composite. Highly textured p‐type ceramic composites were fabricated via uniaxial cold‐pressing and pressureless sintering in air. The unique hexagonal NaxCoO2 template particles, produced through molten‐flux synthesis, allowed precise control over their shape and dimensions, while the matrix was synthesized via a sol–gel synthesis. The integrated NaxCoO2 particles of the textured composite exhibited increased thermal stability, showing no sign of decomposition at 1173 K in air, whereas the sole template particles decomposed at 1073 K during sintering. A 20 wt% template particle content in the textured composites resulted in a remarkably high and nearly temperature‐independent power factor of 8.8 µW cm−1 K2, corresponding to an improvement of 13% compared to that of the pure matrix material. [ABSTRACT FROM AUTHOR]

Designing a nanofluidic membrane with high selectivity and fast ion transport property is the key towards high‐performance osmotic energy conversion. However, most of reported membranes can produce power density less than commercial benchmark (5 W/m2), due to the imbalance between ion selectivity and permeability. Here, we report a novel nanoarchitectured design of a heterogeneous membrane with an ultrathin and dense zirconium‐based UiO‐66‐NH2 metal–organic framework (MOF) layer and a highly aligned and interconnected branched alumina nanochannel membrane. The design leads to a continuous trilayered pore structure of large geometry gradient in the sequence from angstrom‐scale to nano‐scale to sub‐microscale, which enables the enhanced directional ion transport, and the angstrom‐sized (~6.6–7 Å) UiO‐66‐NH2 windows render the membrane with high ion selectivity. Consequently, the novel heterogeneous membrane can achieve a high‐performance power of ~8 W/m2 by mixing synthetic seawater and river water. The power density can be largely upgraded to an ultrahigh ~17.1 W/m2 along with ~48.5 % conversion efficiency at a 50‐fold KCl gradient. This work not only presents a new membrane design approach but also showcases the great potential of employing the zirconium‐based MOF channels as ion‐channel‐mimetic membranes for highly efficient blue energy harvesting. [ABSTRACT FROM AUTHOR]

Organic–inorganic metal halide perovskites (OIMHP's), particularly CH3NH3PbX3 (X = I, Br, Cl) and their derivatives shows favorable properties for energy harvesting such as high absorption coefficients, adjustable band gaps, and low charge recombination rate. The structure and hence nature of bonding between different atoms of these perovskites is known to affect their properties significantly. Tuning of band gap can be achieved in these systems with the help of compositional variation. These systems are studied extensively in the single halide compositions (MAPbI3, MAPbBr3 and MAPbCl3); while, their derivatives seem to have gained less attention though being important for various applications. So, in this work, halide tuning is achieved in derivative perovskite, MAPb(Br1-xClx)3 (x = 0 to 1) and further studied for structural and optical properties along with vibrational properties using X-ray diffraction (XRD), diffuse reflectance spectroscopy, and Raman spectroscopy techniques, respectively. A decrease in the lattice parameter is observed as the Chlorine content increases in the MAPb(Br1-xClx)3 (x = 0 to 1) perovskite. The substitution of Chlorine with Bromine also results in significant increase in the band gap value. In contrast to previous reports, it was clearly observed that the Urbach energy strongly depends on the composition. For the first time, appearance of two features for torsional mode of methylammonium (MA) is discussed even at room temperature, indicative of disorder. It is observed that although the band gap tuning is achieved with the help of halide mixing (Br and Cl), it is also found to introduce disorder in the intermediate compositions; while, the stability increases toward Chlorine compositions. Interestingly, the information of disorder is found to be contained in both the global as well as local measurements which opens up new pathways for studying these materials. This study will lay down a pathway for better understanding of key properties of these hybrid mix halide perovskites which are promising material for futuristic energy applications. [ABSTRACT FROM AUTHOR]

As an inorganic halide perovskite (IHP), CsPbI2Br has generated enormous publicity due to its suitable optical bandgap (≈1.92 eV) and thermal stability. Unfortunately, the terrible phase stability of CsPbI2Br film will cause a phase change in a wet environment and decelerate light response, seriously hindering the progression of IHP photovoltaics. Herein, a synergistic postmodification strategy with CsBr and MABr to achieve high‐quality CsPbI2Br film at a low‐temperature (≈150 °C) and positive perovskite/carbon interface is presented. Adding a small amount of MABr can promote the crystallization of perovskite. The evaporated CsBr accumulates on the grain boundaries and surface of CsPbI2Br and forms Br‐rich perovskite, which provides the protection of CsPbI2Br and segregation of water vapor. The carbon‐based perovskite solar cell (C‐PeSC) with the modified CsPbI2Br harvests a high power conversion efficiency (PCE) of 11.04%. Notably, the unpackaged cell maintains 81% of its original PCE after being stored for 21 days in an air atmosphere with 25–35% humidity. Flexible devices are further manufactured, whose PCE drops to 90% of the initial value during 150 bending cycles. The flexible device also exhibits excellent blue photodetection performances. The maximum responsivity and detection reach 0.68 A W−1 and 8.91 × 1012 Jones, respectively. These findings provide broader avenues for flexible IHP in multifunctional devices. [ABSTRACT FROM AUTHOR]

The seamless integration of advanced triboelectric nanogenerators with fiber material has propelled the rapid advancement of intelligent wearable electronics. The overheating and mechanical abrasion associated with prolonged operation poses a significant challenge for conventional fiber‐based triboelectric materials. Aramid fibers, characterized by high thermal stability, ultra‐high mechanical strength, and excellent insulating properties, can effectively compensate for the limitations of triboelectric materials. However, the intrinsic advantages of aramid fiber triboelectric materials and their general structural design strategies have not yet to be comprehensively elucidated. In this review, the synthesis methods and development history of aramid fiber triboelectric materials in recent years are summarized. Importantly, the unique advantages and development potential of aramid fibers as triboelectric materials are systematically discussed, particularly regarding high‐temperature resistance, high strength, and electrical insulation. Furthermore, the latest advancements in the structural design and performance modulation of aramid fiber triboelectric materials are presented. The aramid fiber‐based self‐powered wearable electronics in high‐temperature warning, impact monitoring, and human energy harvesting are summarized. Finally, the challenges and opportunities facing the future development of aramid fiber‐based triboelectric nanogenerators are discussed. [ABSTRACT FROM AUTHOR]

Structurally well‐defined self‐assembled supramolecular multi‐modular donor‐acceptor conjugates play a significant role in furthering our understanding of photoinduced energy and electron transfer events occurring in nature, e. g. in the antenna‐reaction centers of photosynthesis and their applications in light energy harvesting. However, building such multi‐modular systems capable of mimicking the early events of photosynthesis has been synthetically challenging, causing a major hurdle for its growth. Often, multi‐modularity is brought in by combining both covalent and noncovalent approaches. In the present study, we have developed such an approach wherein a π‐extended conjugated molecular cleft, two zinc(II)porphyrin bearing bisstyrylBODIPY (dyad, 1), has been synthesized. The binding of 1 via a 'two‐point' metal‐ligand coordination of a bis‐pyridyl fulleropyrrolidine (2), forming a stable self‐assembled supramolecular complex (1 : 2), has been established. The self‐assembled supramolecular complex has been fully characterized by a suite of physico‐chemical methods, including TD‐DFT studies. From the established energy diagram, both energy and electron transfer events were envisioned. In dyad 1, selective excitation of zinc(II)porphyrin leads to efficient singlet‐singlet excitation transfer to (bisstyrly)BODIPY with an energy transfer rate constant, kEnT of 2.56×1012 s−1. In complex 1 : 2, photoexcitation of zinc(II)porphyrin results in ultrafast photoinduced electron transfer with a charge separation rate constant, kCS of 2.83×1011 s−1, and a charge recombination rate constant, kCR of 2.51×109 s−1. For excitation at 730 nm corresponding to bisstyrylBODIPY, similar results are obtained, where a biexponential decay yielded estimated values of kCS 3.44×1011 s−1 and 2.97×1010 s−1, and a kCR value of 2.10×1010 s−1. The newly built self‐assembled supramolecular complex has been shown to successfully mimic the early events of the photosynthetic antenna‐reaction center events. [ABSTRACT FROM AUTHOR]

Machine learning (ML) is increasingly applied across various fields, including chemistry, for molecular design and optimizing reaction parameters. Yet, applying ML to experimental data is challenging due to the limited number of synthesized samples, which restricts its broader application in device development. In energy harvesting, photoanodes are crucial for solar-driven water splitting, generating hydrogen and oxygen. We explored electrodes like hematite and bismuth vanadate for photocatalytic uses, noting varied photoelectrochemical performances despite similar preparations. To understand this variability, we applied a data-driven ML approach, predicting photocurrent values and identifying key performance influencers even with limited experimental data in the research development of inorganic devices. We have utilized multiple machine learning algorithms to predict the target value in the calculation process, where the contributions of the dominant descriptors were unknown. We introduced a novel methodology, incorporating clustering to manage multicollinearity from correlated analytical data and Shapley analysis for clear interpretation of contributions to performance prediction. This method was validated on hematite and bismuth vanadate, showing superior predictability and factor identification, and then extended to tungsten oxide and bismuth vanadate heterojunction photoanodes. Despite their complexity, our approach achieved determination coefficients (R2) with a prediction accuracy over 0.85, successfully pinpointing performance-determining factors, demonstrating the robustness of the new scheme in advancing photodevice research. [ABSTRACT FROM AUTHOR]

Electromagnetic generators are conventionally used to harvest energy from large water bodies, but they are ineffective for harvesting low hydro‐energy, such as raindrops or fogs, due to their bulky, heavy and immovable. Unfortunately, developing new strategies that are lightweight, small, and have high conversion efficiency to convert such low hydro‐energy into electricity remains a challenge. Herein, a flexible droplet‐based hybrid electricity generator (DHEG) consisting of a droplet‐based electricity generator (DEG) and an electromagnetic generator (EMG) is proposed to convert the dual energy of water droplets into electricity simultaneously. The DHEG is assembled by facilely merging DEG and EMG using conductive elastic multi‐walled carbon nanotubes/polydimethylsiloxane (MWCNTs/PDMS) film. The MWCNTs/PDMS film can not only serve as a bottom electrode for switching on the DEG, but also as an elastic component for the EMG to vibrate the coil when impacted by water droplets. Activated by a single 58.2 µL droplet falling from a height of 50 cm, the peak voltage, current and power generated by the DHEG are ≈84.6 V, ≈19.85 mA, and ≈595.8 µW, respectively. The energy conversion efficiency of the DHEG is up to ≈13.8%. This flexible hybrid generator may provide a promising strategy for effectively harvesting energy from raindrops. [ABSTRACT FROM AUTHOR]

Artificial light‐harvesting systems (LHSs) with a multi‐step sequential energy transfer mechanism significantly enhance light energy utilization. Nonetheless, most of these systems exhibit an overall energy transfer efficiency below 80%. Moreover, due to challenges in molecularly aligning multiple donor/acceptor chromophores, systems featuring ≥3‐step sequential energy transfer are rarely reported. Here, a series of artificial LHSs is introduced featuring up to 4‐step energy transfer mechanism, constructed using a cyclic peptide‐based supramolecular scaffold. These LHSs showed remarkably high energy transfer efficiencies (≥90%) and satisfactory fluorescence quantum yields (ranging from 17.6% to 58.4%). Furthermore, the structural robustness of the supramolecular scaffold enables a comprehensive study of these systems, elucidating the associated energy transfer pathways, and identifying additional energy transfer processes beyond the targeted sequential energy transfer. Overall, this comprehensive investigation not only enhances the understanding of these LHSs, but also underscores the versatility of cyclic peptide‐based supramolecular scaffolds in advancing energy harvesting technologies. [ABSTRACT FROM AUTHOR]

Nanofluidic energy harvesting from salinity gradients is studied in 2D nanomaterials‐based membranes with promising performance as high ion selectivity and fast ion transport. In addition, moving forward to scalable, feasible systems requires environmentally friendly materials to make the application sustainable. Clay‐based membranes are attractive for being environmentally friendly, non‐hazardous, and easy to manipulate materials. However, achieving underwater stability for clay‐based membranes remains challenging. In this work, the synthetic clay Laponite is used to prepare clay‐based membranes with high stability and excellent performance for osmotic energy harvesting. The Laponite membranes (Lap‐membranes) are stabilized by low‐temperature annealing treatment to effectively reduce the interlayer space, achieving a continuous operation under salinity gradients. Furthermore, the Lap‐membranes conserve integrity while soaking in water for more than one month. The output power density improves from ≈4.97 W m−2 on the pristine membrane to ≈9.89 W m−2 in the membrane treated 12 h at 300 °C from a 30‐fold concentration gradient. Especially, It is found that the presence of interlayer water to be favorable for ion transport. Different mechanisms are proposed in the Lap‐membranes involved for efficient ion selectivity and the states found with varying annealing temperatures. This work demonstrates the potential application of Laponite based nanomaterials for nanofluidic energy harvesting. [ABSTRACT FROM AUTHOR]