Pyroelectric Research Articles

Zipper‐Like Dynamic Switching of Coordination Bonds Gives a Polar Bimetallic Halide Toward Self‐Driven X‐Ray Detection

AbstractPolar molecular crystals hold a promise for controlling bulk physical properties originated in their unique switchable polarity via structural transformation. However, the mechanisms for switching polarization are mainly limited to displacive and disorder‐order phase transitions, which rarely involve the reconstruction of chemical bonds. Here, we have switched and tuned electric polarization in a bimetallic halide, (Neopentylammonium)4AgBiBr8 (1), as verified by light‐excited pyroelectric effect. Most notably, its Ag−Br coordination bonds show a zipper‐like dynamic switching behavior from the ‘locked’ to ‘unlocked’ state, namely, reconstruction of chemical bonds. Coupling with the dynamic ordering of organic cations, this bond‐switching transition makes a contribution to switchable polarization of 1. As expected, its polarity creates pyroelectric effect for self‐driven X‐ray detection with high sensitivity (3.8×103 μC Gy−1 cm−2) and low limit of detection (4.8 nGy s−1). This work on the bond‐switching mechanism provides an avenue to design polar molecular candidate for smart optoelectronic devices.

Zipper-Like Dynamic Switching of Coordination Bonds Gives a Polar Bimetallic Halide Toward Self-Driven X-Ray Detection.

Polar molecular crystals hold a promise for controlling bulk physical properties originated in their unique switchable polarity via structural transformation. However, the mechanisms for switching polarization are mainly limited to displacive and disorder-order phase transitions, which rarely involve the reconstruction of chemical bonds. Here, we have switched and tuned electric polarization in a bimetallic halide, (Neopentylammonium)4AgBiBr8 (1), as verified by light-excited pyroelectric effect. Most notably, its Ag-Br coordination bonds show a zipper-like dynamic switching behavior from the 'locked' to 'unlocked' state, namely, reconstruction of chemical bonds. Coupling with the dynamic ordering of organic cations, this bond-switching transition makes a contribution to switchable polarization of 1. As expected, its polarity creates pyroelectric effect for self-driven X-ray detection with high sensitivity (3.8×103 μC Gy-1 cm-2) and low limit of detection (4.8 nGy s-1). This work on the bond-switching mechanism provides an avenue to design polar molecular candidate for smart optoelectronic devices.

Ultra‐Sensitive, Self‐powered, CMOS‐Compatible Near‐Infrared Photodetectors for Wide‐Ranging Applications

AbstractSelf‐powered near‐infrared (NIR) photodetectors are essential for surveillance systems, sensing in IoT electronics, facial recognition, health monitoring, optical communication networks, night vision, and biomedical imaging. However, silicon commercial detectors need external power to operate and cooling to suppress large dark currents. This work demonstrates a new class of CMOS‐compatible self‐powered NIR photodetector based on ferroelectric 5‐nm thick ZrO2 films which do not require cooling and therefore have two key advantages over Si, and at the same time have comparable performance metrics. At room‐temperature, under 940 nm wavelength illumination (1.4 mW cm−2 power density, 10 Hz repetition rate), and without any power applied, fast rise and fall times of ≈2 and 4 µs, respectively, are achieved in Al/Si/SiOx/ZrO2/ITO devices, along with responsivity, detectivity and sensitivity values of up to ≈3.4 A W−1, 1.2 × 1010 Jones and 4.2 × 103, respectively, far exceeding all other emerging self‐powered systems. Furthermore, dual‐band NIR detection is shown for different NIR wavelengths, proof‐of‐concept feasibility being demonstrated for the smart identification of NIR targets. Therefore, it is demonstrated, for the first time, that coupling together the pyroelectric effect, the photovoltaic effect, and the ferroelectric effect is a novel method to significantly enhance the performance of CMOS‐compatible ZrO2‐based self‐powered photodetectors in the NIR region.

Enhanced Pyroelectric Performances in Textured Na0.5Bi4.5Ti4O15 Ceramics for Infrared Detection.

The pyroelectric effect is extensively used in infrared imaging, detection systems, military equipment, and smart furniture, which require pyroelectric materials to simultaneously possess a high pyroelectric coefficient (p) and a high Curie temperature (Tc) for circuit integration. However, the Tc of commercial lead zirconate titanate (PZT) is limited to 230 °C, imposing an insurmountable challenge in the integration. Here, we investigated the pyroelectricity in Na0.5Bi4.5Ti4O15 (NBT) with a high Curie temperature (∼660 °C), meeting the temperature requirements for integration. Textured NBT ceramics with a high degree of orientation (80%) were fabricated by using tape-casting, resulting in a p of 122 μC m-2 K-1, a 144% improvement over randomly oriented NBT ceramics. This method was also applied to doped NBT ceramics (NBTM-5Nb), achieving an impressive p of 252 μC m-2 K-1, representing a 400% improvement compared to randomly oriented NBT ceramics. Meanwhile, the textured NBTM-5Nb ceramics exhibit excellent figures of merit with Fi = 1.05 × 10-10 m V-1, Fv = 0.09 m2 C-1, Fd = 4.9 × 10-5 Pa-1/2, comparable to the performance of PZT. Furthermore, the textured ceramics exhibit excellent thermal stability, with no performance degradation after annealing at 300 °C, rendering them suitable for circuit integration.

Structural nature of pyroelectric effect revisited: Experimental and theoretical studies of synthetic Ni,Al - rich tourmaline

Tourmaline, the first pyroelectric material discovered, is also a promising borosilicate material with non-linear optical and luminescence properties, high thermal stability, high hardness and variable chemical composition. The structural nature of pyroelectricity in tourmaline is a subject of scientific debate since it requires precise structural studies and measurements at elevated temperatures. Here, an in situ high temperature single-crystal and powder X-ray diffraction studies (up to ∼1000 °C) and the direct pyroelectric measurements (up to ∼200 °C) of synthetic Ni, Al-rich tourmaline were performed. The pyroelectric coefficient was calculated from the structural data. The results demonstrate that polyhedra XO9, YO6 and ZO6 exert the greatest influence on the pyroelectric effect. The pyroelectric coefficient of tourmaline is practically independent of boron-oxygen triangles and silicon-oxygen tetrahedra. The primary pyroelectric coefficient of tourmalines could be calculated from single crystal structural data. This study contributes to the synthesis of tourmalines with the required pyroelectric properties and may be used for the study of the nature and properties of other pyroelectric materials.

Unprecedented Silver-Based Hybrid Pyroelectric Enabling Wide Spectral Photo-Pyroelectricity for Birefringence Photomodulation.

Birefringent crystal, which has the capacity to manipulate polarization light, holds an indispensable position in optics and optoelectronics, while it remains challenging to fulfill the modulation of birefringence. Here, we present wide spectral photo-pyroelectric effect in a silver-based hybrid pyroelectric, (N-CHM)Ag2I3 (N-CHM=N-cyclohexylmethylamine), serving as a feasible strategy to regulate birefringence through light stimuli. As the first silver-based hybrid pyroelectric, (N-CHM)Ag2I3 exhibits strong room-temperature photo-pyroelectricity with a large polarization of ~3.23 μC/cm2 and high voltage responsivity of ~0.96 m2/C across the UV-NIR spectral region. Strikingly, the photomodulation of its in-plane birefringence is established through pyroelectric effect, giving a saturation value of ~1.68×10-2 that is among the highest level achieved to date. This study on the birefringence photomodulation of lead-free hybrid pyroelectric is anticipated to boost future development of new smart optical and optoelectronic devices.

Rationally designed photothermal-pyroelectric Fe0.9Ni0.1S2/ZnSnO3 Z-scheme heterojunction for promoting electrical charge polarization towards optimized photocatalytic H2 evolution and intermolecular N-N coupling reaction

Developing a photocatalytic composite system that can couple hydrogen (H2) evolution and benzylamine (BA) oxidation is a challenging task, especially while avoiding sacrificial agents and value-added chemicals. Here, a practical approach is reported to develop a photothermal-pyroelectric-Fe0.9Ni0.1S2/ZnSnO3 photocatalytic system with core–shell and Z-scheme heterostructure via hydrothermal and annealing methods. Although Fe0.9Ni0.1S2 nanoparticles (NPs) could convert most of near-infrared (NIR) light energy into heat energy to drive the pyroelectric effect of ZnSnO3, it also results in temperature fluctuations (ΔT) in the system, causing natural polarization and thermoelectric effects under the condensed water circulation. As a result, the as-designed Fe0.9Ni0.1S2/ZnSnO3-2 composites could yield up to 7.194 mmol g-1h−1 with exceptional photocatalytic H2 evolution under simulated sunlight. This result is 5.41 and 4.92-fold those of Fe0.9Ni0.1S2 and ZnSnO3, respectively, with 16.66 % apparent quantum yield (AQY) under 365 nm monochromatic light. At the same time, the composites could also oxidize BA and yield up to 6.640 mmol g-1h-1n-benzylidene benzylamine (NBBA) with a 90.2 % selectivity. Due to the synergistic effect of Z-scheme’s built-in electric field and photothermal-pyroelectric of Fe0.9Ni0.1S2/ZnSnO3, the surface charges released on them could direct the charge transfer pathways and restrain their recombination with accelerated electron transfer kinetics, thus extending the carrier lifetime. This work offers a new perspective for designing electrical charge polarized by the photothermal-pyroelectric effect, which can enhance H2 evolution and BA oxidation concurrently.

Ferroelectric Nanomaterials for Energy Harvesting and Self‐Powered Sensing Applications

AbstractThe rapid development of the Internet of Things has introduced new challenges for miniaturized, highly integrated energy harvesters and sensors, promoting the exploration of various novel nanomaterials. Ferroelectric nanomaterials, characterized by large remanent polarization, exceptional dielectric properties, outstanding chemical stability, and diverse electricity generation capabilities, are emerging as promising candidates in a variety of fields. Possessing various mechanisms for electricity generation, including piezoelectric, pyroelectric, photovoltaic, and triboelectric effects, ferroelectric nanomaterials demonstrate their capability for harvesting and sensing multiple energies simultaneously, including light, thermal, and mechanical energies. This capability contributes to the miniaturization and high integration of electronic devices. This article reviews recent achievements in ferroelectric nanomaterials and their applications in energy harvesting and self‐powered sensing. Different categories of ferroelectric nanomaterials, their ferroelectric properties, and fabrication methods are introduced. The working mechanisms and performance of ferroelectric energy harvesters and self‐powered sensors are described. Additionally, future prospects are discussed.

Unveiling Superior Solar-Blind Photodetection with a NiO/ZnGa2O4 Heterojunction Diode.

This investigation presents a self-powered, solar-blind photodetector utilizing a low-temperature fabricated crystalline NiO/ZnGa2O4 heterojunction with a staggered type-II band alignment. The device leverages the pyrophototronic effect (PPE), combining the photoelectric effect in the p-n junction and the pyroelectric effect in the non-centrosymmetric ZnGa2O4 crystal. This synergistic effect enhances the photodetector's performance parameters, thereby outperforming traditional solar-blind photodetectors. The device demonstrates an extremely low dark current of 5.39 fA, a high responsivity of 88 mA/W, and a very high specific detectivity of 2.03 × 1014 Jones under 246 nm light irradiation at 0 V bias. Significantly, due to the PPE, the impact demonstrates a much-enhanced transient response when tested under various light intensities, ranging from 18 to 122 μW/cm2. The photodetector shows a high responsivity of 338 A/W and an outstanding detectivity of 7.1 × 1018 Jones with an applied voltage of -13 V, showing its ability to detect weak signals. Single-crystalline ZnGa2O4 fabricated by MOCVD exhibits significant absorption of deep UV light, and the heterojunction's type-II band alignment with NiO is responsible for its exceptional self-powered pyrophotoelectric detecting and rectifying capabilities.

Construction of Z‐type heterojunction Bi4Ti3O12/g‐C3N4 with pyroelectric effect for enhanced photocatalytic performance

AbstractPhotocatalytic technology has been widely studied, discussed, and tested as a feasible wastewater degradation technology. The present study demonstrated the preparation of g‐C3N4 material using solid‐state sintering method and the construction of Bi4Ti3O12/g‐C3N4 heterostructure via hydrothermal method. This direct contact Z‐type heterojunction improves the wide bandgap of Bi4Ti3O12 monomer, enhances its photoresponsiveness, and thus improves its photocatalytic performance. During the process of photocatalytic experiments, an environment of cold and hot fluctuations were created, and the pyroelectric effect was utilized to induce self‐polarization of the material and formed an internal electric field. It improves the transport ability of electron–hole pairs and suppresses their recombination in the transport path. According to the degradation experiment results, the degradation efficiency of pyroelectric synergistic heterojunction photocatalysis reached 88.7%, which was 2.27 times that of Bi4Ti3O12. It proves that the photocatalysis by pyroelectric synergistic heterojunction has good application prospects.

Preliminary study on temperature distribution and pyroelectric current of LiNbO3 heated by nanosecond pulse laser

In order to reduce the volume of compact neutron generators, a lot of investigations are carried out on generating high voltages by heating pyroelectric crystals with external heating. Laser irradiation is an effective non-contact heating method. Different laser parameters determine the crystal's temperature distribution, impacting the accelerating electric field. A preliminary study on the temperature distribution and pyroelectric current response of LiNbO3 heated by nanosecond pulse laser is presented, including both direct heating and heating with Cu and Ti disks adhered to the crystal. A two-dimensional transient heat transfer and circuit model is constructed in COMSOL. To validate the simulation model of temperature field distribution, FLIR thermal camera is utilized to measure the temperature in laser spot center experimentally. The experimental results coincide with simulations, which prove that the simulation model can predict temperature field distribution of the pyroelectric crystal effectively. This study can benefit the optimization of laser parameters for modulating high-quality deuterium ion acceleration fields.

Unveiling pyroelectricity in ferroelectric planar capacitors with area-selective wet etched hafnium zirconium oxide: from ab initio and multiphysics simulations to experiments

Abstract In this work, a systematic approach aimed at investigating and validating a novel way of realizing pyroelectric harvesting is presented. Generating a direct-current (dc) signal through a temperature gradient within a less than 7 nm-thick ferroelectric zirconium-doped hafnium oxide (HZO) nano-film, embedded in planar interdigitated capacitors on high-resistivity silicon, is a new, simple, effective, and reproducible solution. Temperature-related structural modifications in HZO are first simulated using advanced ab initio calculations. Then, rigorous multiphysics simulations of the final devices provide insight into the expected performance of the pyroelectric harvester, as a function of temperature, contact area, and crystal orientation, showing a maximum open-circuit voltage of up to 900 mV. The fabrication of the harvesters involves the area-selective wet etching of the HZO layer to retain it exclusively in between the fingers of each capacitor. This choice maximizes the pyroelectric effect (which strongly depends on the area) and represents a new paradigm in the development of HZO-based electronics, which are conventionally built on ferroelectric continuous films. Experimental validation at both low frequencies and microwaves confirms the pyroelectric effect, exhibiting a significant increase in the output current for higher temperature gradients, and a generated dc voltage of several hundred millivolts.

Flexoelectronics of a centrosymmetric semiconductor cylindrical nanoshell

Cylindrical shell-type semiconductors are essential for sensing and energy harvesting when integrated into surfaces of certain equipment, such as spacecraft, marine devices, and portable electronics, where mechanical forces play a significant impact on charge transport. Traditionally, such functionalities are only manifested in piezoelectric or pyroelectric crystals that possess non-centrosymmetry. Here, we theoretically investigate electronic behaviors driven by strain gradient-induced flexoelectric polarization in a centrosymmetric semiconductor cylindrical nanoshell, expanding the flexoelectronics in shell structures. The governing equations and accompanying boundary conditions are formulated simultaneously using the principle of virtual work and the fundamental lemma of the calculus of variation. Electromechanical interactions through static bending and forced vibration analyses of the newly developed model are systematically investigated. Under localized force excitation, the distribution of mobile charges is manipulated by tuning loading magnitudes and areas. The effects of doping levels on electric potentials and mobile charges are explored to show the interaction mechanism between flexoelectric and semiconducting properties. Moreover, the natural frequencies and modes of all mechanical displacements, electric potentials, and carrier concentration perturbations within the shell are identified. This paper provides a new approach for designing shell-shaped sensors and energy harvesters specifically for centrosymmetric semiconductors.

Pyroelectric field drived photocatalysis by ZnFe2O4/NaNbO3 heterojunction for dye degradation through integration of solar and thermal energy

A novel composite of ZnFe2O4/NaNbO3 (ZFO/NNO) nanorods with a p-n heterojunction structure was successfully synthesized via the hydrothermal method. The NNO nanorods were heated in situ using the photothermal effect of ZFO and subsequently cooled to room temperature, creating a cyclic heating and cooling process for ZFO/NNO. The catalytic activity of the resulting nanorods was assessed through the degradation of Rhodamine B, reaching 98% degradation efficiency after 180 min, attributed to the synergistic effect of pyrocatalysis and photocatalysis. Compared with NNO and ZFO individually, the enhanced performance of ZFO/NNO can be attributed to several synergistic factors, including the expanded spectral range of light absorption for ZFO, the establishment of the built-in electric field of the p-n junction between ZFO and NNO, and the NNO pyroelectric effect that further improved the charge transfer efficiency. Superoxide radicals and holes generated from photo-induced electrons were identified as the active species. Hydroxyl radicals generated from pyroelectrically-induced charge also participated in catalytic reaction. The combined effect of pyroelectric and photocatalytic processes could significantly improve the coupled pyro-photocatalytic reaction for pyroelectric semiconductor heterostructure, enabling the utilization of multiple energy sources, including solar and thermal energy.

Unprecedented Silver‐Based Hybrid Pyroelectric Enabling Wide Spectral Photo‐Pyroelectricity for Birefringence Photomodulation

Birefringent crystal, which has the capacity to manipulate polarization light, holds an indispensable position in optics and optoelectronics, while it remains challenging to fulfill the modulation of birefringence. Here, we present wide spectral photo‐pyroelectric effect in a silver‐based hybrid pyroelectric, (N‐CHM)Ag2I3 (N‐CHM = N‐cyclohexylmethylamine), serving as a feasible strategy to regulate birefringence through light stimuli. As the first silver‐based hybrid pyroelectric, (N‐CHM)Ag2I3 exhibits strong room‐temperature photo‐pyroelectricity with a large polarization of ~3.23 μC/cm2 and high voltage responsivity of ~0.96 m2/C across the UV−NIR spectral region. Strikingly, the photomodulation of its in‐plane birefringence is established through pyroelectric effect, giving a saturation value of ~1.68×10−2 that is among the highest level achieved to date. This study on the birefringence photomodulation of lead‐free hybrid pyroelectric is anticipated to boost future development of new smart optical and optoelectronic devices.

Ultrafast near-infrared pyroelectric detector based on inhomogeneous plasmonic metasurface

Pyroelectric (PE) detection technologies have attracted extensive attention due to the cooling-free, bias-free, and broadband properties. However, the PE signals are generated by the continuous energy conversion processes from light, heat, to electricity, normally leading to very slow response speeds. Herein, we design and fabricate a PE detector which shows extremely fast response in near-infrared (NIR) band by combining with the inhomogeneous plasmonic metasurface. The plasmonic effect dramatically accelerates the light-heat conversion process, unprecedentedly improving the NIR response speed by 2−4 orders of magnitude to 22 μs, faster than any reported infrared (IR) PE detector. We also innovatively introduce the concept of time resolution into the field of PE detection, which represents the detector’s ability to distinguish multiple fast-moving targets. Furthermore, the spatially inhomogeneous design overcomes the traditional narrowband constraint of plasmonic systems and thus ensures a wideband response from visible to NIR. This study provides a promising approach to develop next-generation IR PE detectors with ultrafast and broadband responses.

Temperature Dependence of the Sensitivity of PVDF Pyroelectric Sensors to THz Radiation: Towards Cryogenic Applications.

The application of terahertz (THz) science in industrial technology and scientific research requires efficient THz detectors. Such detectors should be able to operate under various external conditions and conform to existing geometric constraints in the required application. Pyroelectric THz detectors are among the best candidates. This is due to their versatility, outstanding performance, ease of fabrication, and robustness. In this paper, we propose a compact pyroelectric detector based on a bioriented poled polyvinylidene difluoride film coated with sputtered metal electrodes for in situ absorption measurement at cryogenic temperature. The detector design was optimized for the registration system of the electron paramagnetic resonance (EPR) endstation of the Novosibirsk Free Electron Laser facility. Measurements of the detector response to pulsed THz radiation at different temperatures and electrode materials showed that the response varies with both the temperature and the type of electrode material used. The maximum signal level corresponds to the temperature range of 10-40 K, in which the pyroelectric coefficient of the PVDF film also has a maximum value. Among the three coatings studied, namely indium tin oxide (ITO), Au, and Cu/Ni, the latter has the highest increase in sensitivity at low temperature. The possibility of using the detectors for in situ absorption measurement was exemplified using two typical molecular spin systems, which exhibited a transparency of 20-30% at 76.9 cm-1 and 5 K. Such measurements, carried out directly in the cryostat with the main recording system and sample fully configured, allow precise control of the THz radiation parameters at the EPR endstation.

Enhancing the performance of self-powered heterojunctional ZnO/Cs3Bi2I9 photodetectors through pyroelectric-photovoltaic coupling effect

Bismuth (Bi)-based perovskites are promising materials for near-ultraviolet-to-visible light (NUV–vis) detection. However, their practical application has been limited by relatively weak responsivity and detectivity. In this study, we developed a large-area, low-cost, environmentally friendly self-powered NUV–vis photodetector based on a ZnO/Cs3Bi2I9 heterojunction through a simple drop-coating method. Leveraging the pyroelectric effect, the device demonstrates a high responsivity of 10.48 mA/W, specific detectivity of 7.69 × 1010 Jones, and a fast rise time of 0.9 ms. Moreover, we elucidated the physical mechanism of the self-powered NUV–vis photodetector and systematically analyzed the influence of light power density on photoresponse and response time. This study introduces an effective strategy to enhance the performance of Bi-based perovskite photodetectors under zero voltage bias, leveraging the pyroelectric effect induced in ZnO under ultraviolet illumination and the photovoltaic effect of the Cs3Bi2I9 perovskite. The newly designed ultra-fast self-powered NUV–vis photodetector holds significant promise for diverse research and commercial applications.

Wireless and Opto-Stimulated Flexible Implants: Artificial Retina Constructed by Ferroelectric BiFeO3-BaTiO3/P(VDF-TrFE) Composites.

The degeneration of retinal photoreceptors is one of the primary causes of blindness, and the implantation of retinal prostheses offers hope for vision restoration in individuals who are completely blind. Flexible bioelectronic devices present a promising avenue for the next generation of retinal prostheses owing to their soft mechanical properties and tissue friendliness. In this study, we developed flexible composite films of ferroelectric BiFeO3-BaTiO3 (BFO-BTO) particles synthesized by the hydrothermal method and ferroelectric poly(vinyldene difluoride-trifluoroethylene) (P(VDF-TrFE)) polymer and investigated their applications in artificial retinas. Owing to the coupling of the photothermal effect of BFO-BTO particles and the pyroelectric effect of the P(VDF-TrFE) polymer, the composite films demonstrate a strong photoelectric response (a maximum peak-to-peak photovoltage > 80 V under blue light of 100 mW/cm2) in a wide wavelength range of light (from visible to infrared) with the inherent flexibility and ease of preparation, making it an attractive candidate for artificial retinal applications. Experimental results showed that blind rats implanted with artificial retinas of the composites display light-responsive behavior, showcasing the effectiveness of vision restoration. This study demonstrates a novel approach for employing ferroelectric materials in vision restoration and offers insights into future artificial retina design.

KNN composite ceramics with superior pyroelectric performance for self-powered thermal detector

The thermal detector based on pyroelectric effect has attracted widespread attention due to its self-powering and rapid response. Although phase boundary engineered lead-free potassium sodium niobate [K0.5Na0.5NbO3, KNN] based ferroelectrics exhibit promising for pyroelectric sensor application, the high dielectric constants (εr) of these materials significantly constrain their pyroelectric figures of merit (FOMs), owing to the inverse correlation between FOMs and εr. To address this problem, we innovatively introduce perovskite bismuth sodium titanate [Bi0.5Na0.5TiO3, BNT] with low εr and high pyroelectric coefficient as the second phase to construct a KNN/BNT composite. The introduction of BNT can not only remain the high pyroelectric coefficient (p=7.12 × 10−4 C m−2 K−1) of KNN matrix, but also result in superior FOMs (Fv increased by 74 %), outperforming previous KNN-based pyroelectric ceramics. The excellent pyroelectric performance originates from the unique composite microstructure with compositional heterogeneity. That is, both the low εr BNT enriched phase and refined grain size as well as the promoted vibration of Nb–O octahedron contribute to the superior pyroelectric performance. A self-powered thermal detector with great thermal response has been developed, which also exhibits potential for detecting ultraviolet energy and infrared radiation.