Self-powered Broadband Research Articles

Self-Powered Broadband Photodetection Ranging from X-ray to UV-Vis Light in a Polar Perovskite Induced by Bulk Photovoltaic Effect.

Self-powered broadband photodetection has evoked increased interest in next-generation photoelectronic devices. However, realizing self-powered broadband photodetection in a single material is still a challenge because of the harsh requirements, including powerful built-in field, excellent charge transport behaviors, as well as the broad absorption. Herein, we first realize broadband photodetection in the range from X-ray to UV-vis light in a polar two-dimensional perovskite (2-FBA)2MAPb2I7 (2-FBA = 2-fluorobenzylamine, MA = methylamine) by incorporating an aromatic spacer into a three-dimensional prototype. As a result, (2-FBA)2MAPb2I7 exhibited a superior response to UV-vis light (377 to 637 nm) without voltage bias. Specifically, a high switching ratio of 1.05 × 104, an outstanding responsivity (R) of 1420 mA W-1, and detectivity (D*) of 1.59 × 1013 Jones were achieved under light illumination at 520 nm. Moreover, (2-FBA)2MAPb2I7 achieved a high sensitivity of 46.4 μC Gy-1 cm-2 without voltage bias, two times higher than that of a commercial α-Se film detector (20 μC Gy-1 cm-2). The sensitivity can be further improved to 3316 μC Gy-1 cm-2 at a 50 V bias. These results give insight into the design of 2D perovskites for self-powered broadband photodetection.

Ultrasensitive self-powered broadband ultraviolet photodetectors based on n-(Ga0.9Sn0.1)2O3/n-TiO2 heterojunction

Ga2O3-based self-powered ultraviolet (UV) photodetectors (PDs) have recently attracted much interest, but they need to be fabricated via complex and expensive vacuum equipments, and the photoresponse performances are not quite good. To solve these problems, we have developed high-property (Ga0.9Sn0.1)2O3/TiO2 heterojunction UV PDs by a low-cost, effective, and facile sol-gel way. Sn4+ possesses higher valence in comparison with Ga3+, and Sn-O bonding energy is weaker than Ga-O bonding energy, which are both in favor of increasing electron concentrations of n-type Ga2O3, resulting in improved photocurrent. TiO2 can form type-II band alignment when it contacts with (Ga0.9Sn0.1)2O3, which is beneficial for separating and transporting photo-generated carriers of the heterojunction PDs. Consequently, a high responsivity of 57.86 mA/W, large detectivity of 9.33×1011 Jones, and quick response rate with a rise/decay time of 0.05/0.66 s at a light wavelength of 230 nm and 0 V bias are achieved in the Au/(Ga0.9Sn0.1)2O3/TiO2/FTO heterojunction PDs. More encouragingly, because the (Ga0.9Sn0.1)2O3 and TiO2 possess strong absorption characteristics for UVC, and UVB and UVA light, respectively, the heterojunction self-powered PDs present superior broadband detection capacity across ultraviolet A to ultraviolet C spectrum.

Near-unity quantum efficiency of self-powered broadband photovoltaic black Si photodetectors with passivated Schottky junction

Near-unity quantum efficiency of self-powered broadband photovoltaic black Si photodetectors with passivated Schottky junction

Patterned 3D-graphene for self-powered broadband photodetector

The remarkable ultra-wideband energy capabilities of zero-bandgap two-dimensional (2D) graphene have made it an outstanding material for photon absorption and charge carrier generation across a broad spectrum. However, atomically thick 2D-graphene only exhibits a light absorption efficiency of 2.3%, posing a challenge for graphene-based photodetectors to harness photon energy effectively. This study utilized plasma-enhanced chemical vapor deposition technology and a mask to create in situ patterned 3D-graphene/Si-based Schottky heterojunctions. The porous structure and natural nano-resonant cavities of the 3D-graphene enhanced the probability of light absorption, while the curved and sharp edges and corners of the patterned 3D-graphene concentrated the local electromagnetic field and induced localized surface plasmon resonance. Both theoretical and experimental analyses confirmed the improved light absorption mechanisms and charge transfer of photogenerated carriers under the built-in electric field. The photodetector based on the patterned 3D-graphene/Si Schottky structure exhibits excellent broadband response characteristics spanning from 380 to 1550 nm, with responsivity and specific detectivity of 68.47 A/W and 1.43 × 1012 Jones at a wavelength of 1550 nm. Furthermore, the photodetector demonstrated ultrafast microsecond-level response times (116/120 μs rise/fall times) along with exceptional stability and reliability. The potential applications of as-fabricated photodetector include logic devices such as “AND” and “OR” gates and information encryption. This research holds valuable scientific significance for the design of future optoelectronic devices and provides crucial insights and technical support for developing high-performance Si-based graphene detectors.

Enhanced Self-Powered Broadband Photodetectors Based on 1-D TiO₂/V₂O₅ Core-Cell Heterojunction

Enhanced Self-Powered Broadband Photodetectors Based on 1-D TiO₂/V₂O₅ Core-Cell Heterojunction

Decipher the Wavelength and Intensity Using Photothermoelectric Detectors.

Broadband photodetectors that can decipher the wavelength (λ) and intensity (I) of an unknown incident light are urgently demanded. Photothermoelectric (PTE) detectors can achieve ultrabroadband photodetection surpassing the bandgap limitation; however, their practical application is severely hampered by the lack of deciphering strategy. In this work, we report a variable elimination method to decipher λ and I of the incident lights based on an integrated Ag2Se film-based PTE detector. Nanostructured Ag2Se films with controlled thickness are synthesized using an ion sputtering of Ag and a room-temperature selenization method and then assembled into a detector. Under identical illumination, Ag2Se films of different thicknesses produce varying output photothermal voltages, influenced by factors including λ. By establishing a direct relationship between the photothermal voltage and the absorption of Ag2Se films of varied thickness, we successfully eliminate variables independent of λ, thus determining λ. Subsequently, I is determined by the calibrated responsivity relationship using obtained λ. Our PTE detector achieves a broadband spectrum from 400 to 950 nm and high accuracy, with deviations as low as ∼2.63 and ∼0.53% for deciphered λ and I, respectively. This method allows for self-powered broadband decipherable photodetection without a complex device architecture or computational assistance, which could boost the research enthusiasm and promote the commercialization of PTE broadband detectors.

Realizing enhanced photoresponse for self-powered broadband photodetector with asymmetric contacts based MoTe2/WSe2 van der Waals heterostructure

Self-powered photodetectors constructed by two-dimensional (2D) materials are significant in advanced science and technology with the growing focus on green and energy-efficient solutions. The built-in electric field in photodetector drives efficient separation and transfer of photogenerated electron–hole pairs. However, traditional metal-2D material-metal structures have more interface defects and larger Schottky barrier to hinder carrier transport. In this work, an asymmetric electrode material structure is constructed by adding graphene to provide a more efficient transport channel for photogenerated carriers. Graphene electrodes can play a variety of roles in efficient separation and collection of photogenerated carriers, reducing the barrier and improving the contact quality. Compared with the device using symmetric gold electrodes, the device prepared with asymmetric contacts show optimized performance. The MoTe2/WSe2 heterostructure exhibits brilliant self-powered photoresponse (a responsivity of 268 mA/W and a detectivity of 7.48*1011 Jones). And the rise/decay times are up to 145μs/125μs. Additionally, the detector has a broadband detection capability from visible light to near-infrared. These results provide a promising and simple way to fabricate a MoTe2/WSe2 self-powered broadband photodetector with high performance

Polarity Flipping in SnSe Empowering Wavelength Selective Self-Powered Broadband Photodetection

Polarity Flipping in SnSe Empowering Wavelength Selective Self-Powered Broadband Photodetection

Self-powered broadband photodetectors based on Bi2O2Se with asymmetric contact areas

Self-powered broadband photodetectors are widely used in military reconnaissance, outdoor environmental sensing, wearable medical monitoring. Current commercial broadband photodetectors based on conventional materials are structurally complex, high cost, and external power consumption. 2D materials emerge as promising candidates for the development of novel photodetectors with superior performances. The construction of self-powered photodetectors predominantly employs the heterostructures or metal–semiconductor–metal (MSM) configurations, which still suffer from either multiple steps of material growth, transferring, alignment or various photolithography, film deposition techniques. Herein, a simple and effective asymmetric contact strategy is proposed to fabricate Bi2O2Se-based self-powered broadband photodetectors with asymmetric Au contact areas. The photodetector exhibits excellent performance under 350–1150 nm illumination. The responsivity is as high as 1.38, 4.76, and 0.63 A/W under 350, 550, and 1050 nm, respectively, which are much higher than those of the previously reported self-powered photodetectors based on Bi2O2Se nanosheets. Meanwhile, the self-powered photodetector has a high external quantum efficiency of 1073.16 % at 550 nm. In addition, the photodetector has excellent stability in the air and enables both imaging and optical communication. Owing to the simple architecture, cost-effectiveness, straightforward manufacturing process, and impressive performance, the proposed self-powered photodetectors hold considerable promise for future applications.

Realizing self-powered broadband photodetection with low detection limit in a trilayered perovskite ferroelectric

Realizing self-powered broadband photodetection with low detection limit in a trilayered perovskite ferroelectric

Self-powered broadband photosensing through the pyro-phototronic effect in 1D SnO2 nanoneedles/2D SnS2 nanoflowers heterostructure

Owing to their elevated surface-to-volume ratios and distinctive geometrical attributes, low-dimensional materials, specifically 1D nanoneedles, and 2D nanosheets, have garnered significant interest in the pursuit of advancing broadband photodetectors with heightened performance capabilities. The increasing attention directed towards metal chalcogenides can be ascribed to their remarkable characteristics, including elevated electron mobility, outstanding chemical stability, and versatile utility across various scientific domains such as sensing, energy storage applications, supercapacitors, and lithium-ion batteries. This study introduces a novel photodetector based on 1D SnO2 nanoneedles/2D SnS2 nanoflowers heterostructure synthesized through a hydrothermal method. The photodetector demonstrates enhanced peak-to-peak transient currents, with factors of 9214 %, 33291 %, 121972 %, 109091 %, and 7496 % at wavelengths of 365, 456, 532, 632, and 850 nm, respectively, compared to pristine SnS2, and exhibits an enhancement in pyroelectric current with factors of 16733 %, 97643 %, 219400 %, 291333 %, and 26777 % at the corresponding wavelengths. Upon the incorporation of the pyro-phototronic effect in the heterostructure, the responsivity of the photodetector undergoes a significant enhancement, reaching values of 3.65, 2.40, 9.28, 10.44, and 2.71 mA/W, corresponding to improvements of 1952 %, 2600 %, 28114 %, 18545 %, and 491 % at the respective wavelengths, compared to photovoltaic responsivity, under zero bias. This study offers an effective approach to enhancing the capabilities of broadband photodetectors by integrating the pyro-phototronic effect in mixed-dimensional photodetectors.

Wavelength-modulated polarity switch self-powered Bi2Se3/GaN heterostructure photodetector

Van der Waals and wide-bandgap materials-based heterostructures have garnered substantial attention in developing self-powered broadband photodetectors owing to their exceptional photovoltaic capabilities. These materials also hold great potential for breakthroughs in optoelectronics. However, limitations to low selectivity constrain the potential of heterostructures-based broadband detectors. Here, we design wavelength-selective polarity switching in a heterostructure photodetector consisting of bismuth selenide (Bi2Se3) and gallium nitride (GaN). The analysis revealed a positive photocurrent under ultraviolet-C illumination to visible wavelength, whereas a negative photocurrent under infrared wavelengths at zero applied bias. The exposure to distinct optical wavelengths leads to an inversion in the electric field polarity across the junction, resulting in polarity switching. The fabricated Bi2Se3/GaN self-powered ultra-broadband photonic device demonstrates a peak photoresponsivity of 584 mAW−1 (−297 mAW−1) at 355 nm (1405 nm) wavelength illumination and can detect weak signals up to 650 femto-watt. Our strategy revealed alternative avenues for developing polarity-switchable, self-powered ultra-broadband photodetectors, offering a first step towards creating wavelength-adaptable sensors for future applications.

Alkali metal ion passivation of lead-free perovskite film for high responsivity self-powered broadband photodetectors

All-inorganic lead-free bismuth-based perovskites have attracted great interest in the optoelectronic applications due to their low toxicity and excellent stability. However, the inherent polycrystalline (PC) of perovskite films suffers severe charge recombination due to the large numbers of trap density. Herein, high-quality Cs3Bi2I9 (CBI) PC thin films are prepared by solution process with alkali sodium (Na+) cation doping strategy, resulting large grain size and lower trap density. Afterward, the photoelectrochemical-type detectors based on Na+ doped CBI thin film is constructed for the first time. The photodetector displays a broadband photoresponse covering ultraviolet (UV), visible and near-infrared (NIR) ranges. Significantly, by precisely controlling Na+ doping concentration, the performance of photodetector can be largely enhanced with the highest responsivity of 53.38 mA/W and detectivity of 5.99 × 109 Jones without bias, and these results exceed the performance of most reported CBI PC thin film based photodetectors. In addition, the photodetector exhibits an obvious increase in photoresponse and outstanding photo-stability after more than 150 on/off cycles. Finally, the mechanism of Na+ doping is further discussed. These results provide an outstanding example for the preparing high-quality CBI PC thin film and also demonstrate the great potential of CBI in the application of self-powered broadband photodetectors.

Self-Powered Broadband Photodetector Based on NiO/Si Heterojunction Incorporating Graphene Transparent Conducting Layer.

In this study, a self-powered broadband photodetector based on graphene/NiO/n-Si was fabricated by the direct spin-coating of nanostructured NiO on the Si substrate. The current-voltage measurement of the NiO/Si heterostructure exhibited rectifying characteristics with enhanced photocurrent under light illumination. Photodetection capability was measured in the range from 300 nm to 800 nm, and a higher photoresponse in the UV region was observed due to the wide bandgap of NiO. The presence of a top graphene transparent conducting electrode further enhanced the responsivity in the whole measured wavelength region from 350 to 800 nm. The photoresponse of the NiO/Si detector at 350 nm was found to increase from 0.0187 to 0.163 A/W at -1 V with the insertion of the graphene top layer. A high photo-to-dark current ratio (≃104) at the zero bias indicates that the device has advantageous application in energy-efficient high-performance broadband photodetectors.

In-situ fabrication of on-chip 1T’-MoTe2/Ge Schottky junction photodetector for self-powered broadband infrared imaging and position sensing

In-situ fabrication of on-chip 1T’-MoTe2/Ge Schottky junction photodetector for self-powered broadband infrared imaging and position sensing

Solution processed self-powered broadband flower-like Zn(Al)O-mixed metal oxide dye sensitized photodetector

This article elucidates a solution-based framework through which a novel self-powered broadband Zn(Al)O-mixed metal oxide (MMO) photodetector treated with organic 535-bisTBA dye (N719) was reported. The deposited MMO layer exhibited flower-like morphology with sheet thickness of 19.4 nm alongside optical bandgap of 3.11 eV, while MMO treated with N719 delivered broad absorbance (450–600 nm). Further, pristine MMO and N719-treated photodetectors responded coherently to the utilized wavelengths with photocurrent of 35.7 and 56.2 μA at 405 and 530 nm, respectively. In conjunction, the spectral-response (Rλ) of pristine MMO device revealed visible blind feature wherein N719-treated photodetector exhibited broad Rλ throughout 375-625nm. The time-resolved characteristics demonstrated response time of 0.85 and 0.80 sec. for pristine MMO and N719-treated devices, respectively. The fabricated photodetectors expressed considerable linear power dependency (R20.99) at 0 bias evidencing self-power feature of the proposed geometry.

Self-powered broadband RGB imaging photodetector based on air-stabilized Bi2Te3 nanosheets

Room temperature self-powered broadband (RTSPBD) response photodetectors have received considerable attention and are also very helpful in alleviating today's energy and environmental crisis. Herein, bismuth telluride (Bi2Te3) nanosheets were successfully synthesized and assembled into an RTSPBD photodetector. The Bi2Te3 photodetector exhibits excellent response characteristics: wide spectral range, maximum responsivity (10.254 mA/W, 435 nm), photocurrent density (106 μA/cm2), Ion/Ioff (71, 365 nm, 25 mW/cm2), rise/decay time (τrise = 0.0475 s and τdecay = 0.0468 s) and cycling stability. A superior responsivity from the ultraviolet to infrared (UV-IR) region is observed, which is attributed to the fact that the narrow bandgap topological insulating state of Bi2Te3 provides a fast charge transport channel for electrons generated by the photovoltaic effect. In addition, it was found that these devices have potential applications in red-green-blue (RGB) triple primary color imaging. It is anticipated that this work will provide a great promising candidate material for the design and preparation of high-performance RTSPBD photodetection imaging devices in the future.

Self-Powered Broadband Photodetectors Based on Large-Scale Continuous Films of Weyl Semimetal WTe2

Self-Powered Broadband Photodetectors Based on Large-Scale Continuous Films of Weyl Semimetal WTe₂

Investigation of In2SexOy/In2Se3/Si dual-junction photodiode for self-powered broadband photodetection

We report a dual-junction strategy for fabricating a high-performance In2SexOy/In2Se3/Si heterojunction photodiode by oxidizing the epitaxial In2Se3 thin films. The device exhibits a suppressed dark current (4.2 × 10−11 A) and enhanced photocurrent at zero bias, benefiting from the double built-in electric fields. Consequently, it demonstrates excellent and uniform self-powered broadband (255–1050 nm) photodetection performance with the typical responsivity of several hundred mA/W, and detectivity of over 5 × 1011 Jones. Moreover, a fast response speed with a response time of 0.20 ms is achieved. Our investigation offers a potential route to construct full-spectrum photodetectors.

A Self-Powered Broadband Photodetector with High Photocurrent Based on Ferroelectric Thin Film Using Energy Band Structure Design

Self-powered photodetectors have the advantages of high sensitivity, sustainability, and small size and have become a research hotspot in advanced optoelectronic systems. However, the low output photocurrent density seriously hinders the practical application of ferroelectric self-powered photodetectors. Herein, the high-efficiency photoelectric detection performance of the Bi1-xHoxFeO3 ferroelectric self-powered photodetector is realized by doping Ho. The responsivity (R) and detectivity (D*) can reach 0.0159 A/W and 1.94 × 1011 Jones under monochromatic light with a wavelength of 900 nm. Meanwhile, the R and D* can reach 0.022 A/W and 2.65 × 1011 Jones under sunlight. These excellent photodetection performances are attributed to the high short-circuit current density (Jsc). When the Ho content is 6%, the output photocurrent reaches up to 0.81 mA/cm2. The systematic structure and photo-electric characteristic analysis suggest that the decrease in the band gap leads to the generation of a larger photocurrent while the ferroelectric polarization is reduced slightly. This work provides a new way to obtain high-performance self-powered photodetectors.