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A Photothermal Solar Tunnel Radiator (PSTR) is designed and developed by employing multiple transparent photothermal glass panels (TPGP). The primary objective is to pioneer a transformative approach to achieve energy-neutral building heating utilities, exemplified by a lab-scale "Photothermal Solar Box" (PSB) exclusively heated with TPGP under natural sunlight. The PSTR presents a novel paradigm for sustainable energy, enabling direct solar energy capture through transparent glass substrates with photothermal coatings. The high transparency of Fe3O4@Cu2-xS coated glass substrates enhance efficient solar harvesting and photothermal energy generation within the Photothermal Solar Box. The system demonstrates an impressive thermal energy output, reaching up to 9.1x105 joules with 8 photothermal panels in parallel. Even under colder conditions (ambient temperature: -10 °C), with accelerated heat loss, the interior temperatures of the PSB with partial thermal insulation achieve a commendable 35 °C, showcasing effective photothermal heating in cold weather. These findings indicate the system's resilience and efficiency in harnessing solar energy under diverse conditions, including partial cloudy weather. The initiative contributes to broader sustainability goals by providing a scalable and practical alternative to traditional solar heating methods, aligning with the global mission for a cleaner, greener future. 

Among major energy conversion methods, photovoltaic (PV) solar cells have been the most popular and widely employed for a variety of applications. Although a PV solar panel has been shown as one of the most efficient green energy sources, its 2D surface solar light harvesting has reached great limitations as it requires large surface areas. There is, therefore, an increasing need to seek solar harvest in a three-dimensional fashion for enhanced energy density. In addition to a conventional 2D solar panel in the x-y area, we extend another dimension of solar harvesting in the z-axis through multiple CdTe solar panels arranged in parallel. The high transparency allows sunlight to partially penetrate multiple solar panels, resulting in significantly increased solar harvesting surface area in a 3D fashion. The advantages of the 3D multi-panel solar harvesting system include: i) enlarged solar light collecting surface area, therefore increased energy density, ii) the total output power from multiple panels can exceed that of the single panel, and iii) significantly reduced surface area needed for densely populated cities. With five CdTe solar panels of different transparencies in parallel, the multilayer system can produce collective output power 233% higher than that of the single solar panel under the same surface area when arranged in descending (i.e., PV panel with the highest transparency on top and lowest at bottom). The PCE of the multi-panel system has also increased 233% in descending order indicating the viability of 3D solar harvesting. The multi-panel system will dimensionally transform solar harvesting from 2D to 3D for more efficient energy generation. 

The efficiencies of photovoltaic (PV) and thermoelectric (TE) have been limited by the intrinsic properties to ~ 25 % and ~ 10 %, respectively. In current applications, photovoltaics utilizes the shorter wavelength end of the solar spectrum but suffer decreases in efficiency from heating caused by IR absorption. The novel tunable nanostructures of new hybrids eliminate this problem by directing thermal energy from longer wavelengths to the thermoelectric device. Solar light is harvested through transparent hybrid and segregated into different wavelengths: the IR is absorbed by the hybrid which is photothermally heated up to ~100 °C for the required thermoelectric temperature span; the UV/visible is directed to PV with reduced IR components, therefore significantly reducing heating. In this way, both PV and TE operate jointly by separately utilizing the full spectrum of solar light. The novel hybrid functions not only as a photothermal heater for TE but also a wavelength segregator enabling the PV and TE devices to synergistically produce electrical energy with much greater system efficiency. Also identified is the operating structural mechanism on spectral tunability and photothermal effect of the photonic hybrids. 

Photovoltaic solar cells have been extensively used for various applications and are considered one of the most efficient green energy sources. However, their 2D surface area solar harvesting has limitations, and there is an increasing need to explore the possibility of multiple layer solar harvest for enhanced energy density. To address this, we have developed spectral-selective transparent thin films based on porphyrin and iron oxide compounds that allow solar light to penetrate multiple layers, significantly increasing solar harvesting surface area and energy density. These thin films are designed as photovoltaic (PV) and photothermal (PT) panels that can convert photons into either electricity or thermal energy for various green energy applications, such as smart building skins and solar desalination. The advantages of this 3D solar harvesting system include enlarged solar light collecting surface area and increased energy density. The multilayer system transforms the current 2D to 3D solar harvesting, enabling efficient energy generation. This review discusses recent developments in the synthesis and characterization of PV and PT transparent thin films for solar harvesting and energy generation using multilayers. Major applications of the 3D solar harvesting system are reviewed, including thermal energy generation, multilayered DSSC PV system, and solar desalination. Some preliminary data on transparent multilayer DSSC PVs are presented. 

A Cold Atmospheric Plasma (CAP) apparatus was designed and developed for SARS-CoV-2 killing as evaluated by pseudotyped viral infectivity assays. The reactive species generated by the plasma system was fully characterized by using Optical Emission Spectroscopy (OES) measurement under given conditions such as plasma power, flow rate, and treatment time. A variety of reactive oxygen species (ROS) and reactive nitrogen species (RNS) were identified from plasma plume with energies of 15–72 eV in the frequency range between 500–1000 nm. Systematic virus killing experiments were carried out, and the efficacy of CAP treatment in reducing SARS-CoV-2 viral infectivity was significant following treatment for 8 s, with further enhancement of killing upon longer exposures of 15–120 s. We correlated killing efficacy with the reactive species in terms of type, intensity, energy, and frequency. These experimental results demonstrate effective cold plasma virus killing via ROS and RNS under ambient conditions. 

The effects of dipole interactions on magnetic nanoparticle magnetization and relaxation dynamics were investigated using five nanoparticle (NP) systems with different surfactants, carrier liquids, size distributions, inter-particle spacing, and NP confinement. Dipole interactions were found to play a crucial role in modifying the blocking temperature behavior of the superparamagnetic nanoparticles, where stronger interactions were found to increase the blocking temperatures. Consequently, the blocking temperature of a densely packed nanoparticle system with stronger dipolar interactions was found to be substantially higher than those of the discrete nanoparticle systems. The frequencies of the dominant relaxation mechanisms were determined by magnetic susceptibility measurements in the frequency range of 100 Hz–7 GHz. The loss mechanisms were identified in terms of Brownian relaxation (1 kHz–10 kHz) and gyromagnetic resonance of Fe3O4 (~1.12 GHz). It was observed that the microwave absorption of the Fe3O4 nanoparticles depend on the local environment surrounding the NPs, as well as the long-range dipole–dipole interactions. These significant findings will be profoundly important in magnetic hyperthermia medical therapeutics and energy applications. 

The US highway system features a huge flux of energy transportation in terms of weight, speed, volume, flow density, and noise levels, with accompanying environmental effects. The adverse effects of high-volume traffic cause health concerns for nearby residential areas. Both chronic and acute exposure to PM 2.5 have detrimental effects on respiratory and cardiovascular health, and motor vehicles contribute 25–35% of direct PM 2.5 emissions. In addition to traffic-related pollutants, residing near major roadways is also associated with exposure to increased noise, and both affect the health and quality of life of residents. While regulatory and policy actions may reduce some exposures, engineering means may offer novel and significant methods to address these critical health and environmental issues. The goal of this study was to harvest highway-noise energy to induce surface charge via a piezoelectric material to entrap airborne particles, including PM 2.5. In this study, we experimentally investigated the piezoelectric effect of a polymethyl methacrylate (PMMA) sheet and ethylene propylene diene monomer (EPDM) rubber foam on the entrapment of copper (II)-2,4 pentanedione powder (Cu II powder). Appreciable voltages were induced on the surfaces of the PMMA via mechanical vibrations, leading to the effective entrapment of the Cu II powder. The EPDM rubber foam was found to attract a large amount of Cu II powder under simulated highway noise in a wide range, of 30–70 dB, and at frequencies of 700–1300 Hz, generated by using a loudspeaker. The amount of Cu II powder entrapped on the EPDM rubber-foam surfaces was found to scale with the SPL, but was independent of frequency. The experimental findings from this research provide a valuable base for the design of a robust piezoelectric system that is self-powered by harvesting the wasted sound energy from highway noise and reduces the amount of airborne particles over highways for effective environmental control.