Absorption In Wavelength Range Research Articles

High‐Performance Self‐Powered PEC Photodetectors Based on 2D BiVO4/MXene Schottky Junction

AbstractAs an emerging field, self‐powered photoelectrochemical (PEC) photodetectors have gradually attracted extensive attention thanks to the unique working characteristics of low preparation cost, strong tunability of device performance, and environmental friendliness. However, short absorption wavelength range, low efficiency of visible light utilization, and low responsivity remain challenges for performance improvements. Here, the PEC photodetectors based on the 2D BiVO4/MXene Schottky junction structure, which shows excellent performance with high photocurrent density (≈3.90 mA cm−2 at 0 VSCE under AM 1.5 G, 150 mW cm−2), good responsivity (790.2 mA W−1 under 447 nm), fast response time (tr/tf = 8/14 ms), and long‐term stability (keep 17 000 s and 22 000 cycles) are fabricated. These can be attributed to the built‐in electric field at the BiVO4/MXene Schottky junction interface, which accelerates the transfer of photogenerated electrons and holes, and inhibits interfacial charge recombination. Additionally, the MXene nanosheets improve the absorption of visible‐light‐induced photons on the valence band of BiVO4. These excellent properties show that this work provides a scientific experimental reference for the further development of PEC photodetectors.

Unraveling the Synergistic Effects of Thiazolidine Co‐Sensitizers in Dye‐Sensitized Solar Cells

ABSTRACTDye‐sensitized solar cells (DSSCs) have garnered significant attention as a promising photovoltaic technology because of their low cost and simplicity. However, the development of efficient organic sensitizers remains a challenge. In this study, we report the synthesis and characterization of two novel organic co‐sensitizers, CD‐1 and TD‐2, based on a thiazolidine core structure and the incorporation of carbazole and triphenylamine donor moieties, respectively. Co‐sensitizers were designed to leverage the strong electron‐donating abilities of these donors to facilitate efficient light‐harvesting and charge‐transfer processes. In‐depth analyses of the spectroscopic and electrochemical properties provided insights into the characteristics of TD‐2 compared with those of CD‐1. TD‐2 displayed a wider range of absorption wavelengths, a narrower energy gap (2.19 eV), and a higher energy level for its (HOMO) than that of CD‐1. These distinctions are attributed to the enhanced capacity of TD‐2 to donate electrons and the elongated π‐conjugation of the triphenylamine component. Upon sensitization, the TD‐2 scored efficiency reached 5.10% and co‐sensitized with N719 dye achieved the highest efficiency, reaching 7.95%. Both sensitizers increased the efficiency of N719 by co‐sensitization (TD‐2 + N719), with an efficiency higher than 15% compared with N719.

Steady and transient modeling of dye-sensitive solar cells: The impact of electrode thickness and dye specifications

Investigating the impact of dye compounds on cell performance is crucial for advancing dye-sensitized solar cells (DSSCs). This research focuses on the sensitivity analysis of the effect of critical parameters to enhance DSSC efficiency using a thermo-electric numerical model. These parameters include dye types, trapping parameters, diffusion coefficients, and photoanode thickness. When the type of dye changes, in fact, both physical and chemical properties (molar absorption coefficient, etc.) Change, but to avoid the complexity of solving the equations and only to evaluate the effect of the absorption wavelength range on the cell performance only changes in physical properties are considered. The model calculates steady and transient currents under actual weather conditions and sunlight. It incorporates time/space-dependent relationships for increased accuracy and examines electron, iodide, and triiodide ion interactions under varying environmental conditions. Key concepts include the quasi-Fermi level and the multiple trap model, assuming that trapping processes are faster than electron transport and recombination. The results showed that increasing the trapping parameter can affect the transient current behavior, also increasing the thickness of the photoanode and the wavelength range of the dye increases the efficiency of the cell, so that the N749-BD provides the best performance. The findings provide insights into current–voltage characteristics, electron production, and the effects of photoanode thickness and dye types on cell performance, offering pathways for optimizing DSSC technology.

Preparation and Properties of 3D Spherical Bi2S3/Bi2O2CO3 Photocatalytic Materials Self‐Assembled by 2D Nanosheets

ABSTRACTThe micro‐morphology of photocatalytic materials has a great influence on their photocatalytic performance. Quantum dots can provide the plasmon resonance effect and broaden the wavelength range of light absorption. In this study, a kind of 3D spherical flower‐like structure was constructed by self‐assembly of 2D nanosheets, the Bi2S3 particles with 5 ± 1 nm diameter were modified on the surfaces of Bi2O2CO3 nanosheets to prepare the Bi2S3/Bi2O2CO3 composite. The energy level difference (0.45 eV) between the conduction bands (CB) of Bi2S3 and Bi2O2CO3 led to which the e− was transferred to CB of Bi2O2CO3. The energy level difference (0.83 eV) between the CB of Bi2O2CO3 and the valence band (VB) of Bi2S3 was much smaller than the band gap (1.28 eV) of Bi2S3, and it led to which the electrons on the CB of Bi2O2CO3 were recombined with the holes on the VB of Bi2S3. A kind of innovative type heterojunction was constructed between Bi2S3 and Bi2O2CO3, which encouraged the photogenerated h+ and ·OH to be located on the VB of Bi2O2CO3 with the strongest oxidation potential, the prepared material showed excellent performance for the photodegradation of RhB, and the active groups were also controlled in the photocatalysis process.

(Invited) In Situ and Operando Scattering Studies on Quantum Dot-Based Devices

Colloidal quantum dots (QDs) made e.g. of PbS are attractive for various optoelectronic applications due to their tunable band gap with a large absorption wavelength range from the visible to the near-infrared region. Moreover, due to the high intrinsic permittivity, the exciton binding energy of PbS is smaller than in cadmium chalcogenide QDs and polymer materials, which is beneficial for devices driven by charge carrier generation and transport, e.g. photovoltaics and photodetectors.In this work, we introduce wet chemical deposition methods beyond spin coating such as printing and spray deposition of QDs as a facile and potentially large-scale deposition method for high-performance photodetectors. The inner structures including the inter-dot distance of neighboring QDs and the structure, in the deposited QD solids, are studied by grazing-incidence small-angle X-ray scattering (GISAXS). In addition, the facet orientation of the QDs in the QD solids is characterized by grazing-incidence wide-angle X-ray scattering (GIWAXS). In particular, in situ GISAXS/GIWAXS studies during film formation are able to provide detailed information about the complex kinetic processes [1,2]. Operando GISAXS/GIWAXS studies on QD-based devices such as solar cells bring an in-depth understanding of the degradation mechanisms, which is key for improving the device stability and thereby bringing these novel materials into real-world applications [3]. Superlattice deformation in QD films on flexible substrates via uniaxial strain is followed in situ with GISAXS, providing a fundamental understanding of the impact of strain on the performance of flexible devices based on QD films, such as wearable electronics and next-generation solar cells on flexible substrates [4]. Nanoscale Horiz. 5, 880-885 (2020)Nano Energy 78, 105254 (2020)Energy Environ. Sci. 14, 3420-3429 (2021)Mater. Horizon 8, 383-395 (2023)

Tunable wideband terahertz absorber based on single-layer patterned graphene

In this study, we propose and validate a broadband terahertz perfect absorber. The absorber has a simple structure, which consists of a gold (Au) substrate, a TOPAS dielectric layer and a patterned graphene layer. By the simulations, a broad absorption band can be obtained with a high absorption above 90% between 3.31 THz and 7.15 THz, and the relative bandwidth reaches 73.4%. Meanwhile, the absorption higher than 99% is between 3.81 THz and 6.6 THz with a relative bandwidth of 53.6%. The mechanism of the surface excited plasma (SPP) and electromagnetic dipole resonance are responsible for its almost perfect broadband absorption. By changing the Fermi energy level of the graphene layer, the flexible broadband absorption spectra can be acquired. By varying the geometrical parameters of the structure, a wider spectral range of absorption wavelengths can be realized. For both TE and TM polarization, the absorption can remain above 90% over a wide range of incidence angles. Due to the independent tunability and high absorption of the proposed device, it has great potential applications in terahertz imaging, smart absorption, detectors and communications.

Directed Assembly of Ordered Mixed-Spacer Quasi-2D Halide Perovskites through Homomeric Chains of Intermolecular Bonds.

Two-dimensional (2D) halide perovskites (HPs) are of significant interest to researchers because of their natural structural frameworks and intriguing optoelectronic properties. However, the direct fabrication of ordered mixed-spacer quasi-2D HPs remains challenging. Herein, a synthetic strategy inspired by the principle of supramolecular synthons is employed for the self-assembly of a series of ordered mixed-spacer bilayered HPs. The key innovation involves the introduction of intermolecular hydrogen bonds using a bifunctional 3-aminopropionitrile cation. Three homogeneous n = 2 structures are obtained, with a subtly ordered perovskite connected by two distinct types of organic cation layers, resulting in a recurrent ABAB' stacking sequence. These three compounds exhibit attractive semiconducting properties. Moderate bandgaps in the range of 2.70 to 2.76eV with an absorption wavelength range of 448-459nm exhibit excellent photoelectric response. Moreover, the ordered structures facilitate excellent polarization-sensitive photodetection, with an impressive on/off ratio of 103. The response speed ranged from 298 to 381 µs, and the out-of-plane polarization-related dichroism ratio is determined to be 1.19. Such ordered mixed-spacer bilayered perovskites have not been reported. These results enrich the HPs system and play a significant role in the direct assembly of novel perovskites with ordered structures.

Photodegradation of polychlorinated biphenyls in water/nitrogen-doped silica and air/nitrogen-doped silica systems: Kinetics, mechanism and quantitative structure activity relationship (QSAR) analysis

Developing efficient and low-cost photocatalytic materials is essential for removing polychlorinated biphenyls (PCBs). In this work, the photodegradation process of fourteen representative polychlorinated biphenyls (PCBs) in both water/nitrogen-doped SiO2 (N-SiO2) and air/N-SiO2 systems was studied. The photodegradation kinetics of PCBs is consistent with the pseudo-first-order kinetic equation. The variation in the degradation effects of different PCBs in the two systems is primarily related to the position of the Cl substituent and the effective absorption wavelength range of PCBs. A total of fourteen intermediates for 4′-Dichlorobiphenyl (PCB-15), 2,2′,4,4′,6,6′-Hexachlorobiphenyl (PCB-155), and 2,2′,3,3′,4,4′,5,5′,6,6′-Decachlorobiphenyl (PCB-209) generated from four reaction pathways were identified based on both mass spectrometry analysis and theoretical calculations. Using the values of lnk (k denotes pseudo-first-order kinetic constants) for the 11 PCBs in the training set and the calculated molecular and structural parameters, quantitative structure-activity relationship (QSAR) models for the two systems were constructed by using multiple linear regression (MLR) method to better understand the factors affecting the photodegradation rate of PCBs. The QSAR equations were obtained with Cl atom substitution at position 3 (N3) as the main parameter, which were lnk = −1.98 - 0.19 N3 for the water/N-SiO2 system and lnk = −1.56 - 0.34 N3 for the air/N-SiO2 system, with the correlation coefficient (R2) of 0.66 and 0.73, leave-one-out cross-validation (Q2LOO) of 0.51 and 0.59, respectively, and bootstrapping validation coefficients (Q2BOOT) values of both 0.74, confirming that the models were well fitted and showed high robustness and prediction ability. This study provides valuable insights into photocatalytic degradation studies of PCBs.

Preparation and Photothermal Properties of Accordion‐Like MXene/Sodium Acetate Trihydrate Composite Phase Change Materials

Phase change materials (PCMs) are promising options for thermal energy storage. Combining sodium acetate trihydrate (SAT) with MXene, the composite phase change materials (CPCMs) have been prepared. The surface morphology, thermal storage performance, and solar energy photothermal conversion efficiency of the CPCMs with various MXene contents are analyzed. According to the microstructure morphology analysis, MXene is accordion‐shaped, and tightly associated with SAT. Differential scanning calorimetry measurement results show that CPCMs possess high latent heat and suitable phase change temperature for the applications of solar heat storage. The absorption wavelength range of SAT/MXene is extended from 200–258 nm to 200–497.7 nm with a photothermal conversion efficiency of 81.3%. SAT/MXene‐2%, SAT/MXene‐8%, and SAT/MXene‐14% have thermal conductivities of 0.84, 1.14, and 1.47 W/ (m · K), respectively, which are higher by 44.9%, 96.6%, and 153.4% than 0.59 W/ (m · K) of pure SAT. CPCMs exhibit excellent thermal stability and reliable cycling stability after 50 cycles, which show that MXene can prevent leakage during the solid‐liquid phase transition process. The expansion of PCM's practical applicability and MXene/SAT composites with good photothermal characteristics create a theoretical foundation for the effective use of renewable energy sources.

Single atoms meeting 2D materials: an excellent configuration for photocatalysis.

Photocatalysis has problems such as low light absorption efficiency and rapid recombination of photogenerated electron-hole pairs. Many studies have been conducted to improve these issues. This review encapsulates the progress and applications of two pioneering research fields in catalysis: single-atom and two-dimensional (2D) material catalysts. The advent of this new type of catalysts, which integrates single atoms onto 2D materials, has seen remarkable growth in recent years, offering distinctive advantages. The article delves into the array of synthesis methods employed for loading single atoms onto 2D materials, including the wet chemical approach, atomic layer deposition technique, and thermal decomposition method. A highlight of the review is the superior attributes of single-atom catalysts supported on 2D materials (SACs-2D) in photocatalysis, such as extending the light absorption wavelength range, enhancing the efficiency of photogenerated electron-hole pair separation, and accelerating redox kinetics. The review meticulously examines the diverse applications of SACs-2D photocatalysis, which encompass water splitting for hydrogen generation, carbon dioxide reduction, degradation of organic pollutants, nitrogen fixation and hydrogen peroxide synthesis. These applications demonstrate the potential of SACs-2D materials in addressing pressing environmental and energy challenges. Finally, this article evaluates the current state of this burgeoning field, discussing the opportunities and challenges ahead.

Highly efficient sunlight-driven LSPR-enhanced core-shell Ag dendrite/g-C3N4 composite photocatalysts

Noble metal nanostructures with localized surface plasmon resonance (LSPR) effect can be employed to enhance the light absorption ability of photocatalysts. However, it has been a challenge to control the size and morphology of noble metal nanostructures to manipulate the LSPR wavelength and improve the performance of photocatalysts. Herein, an Ag dendrite (AgD) composed of Ag nanorods with different sizes was facilely constructed by a displacement reaction, and sunlight-driven LSPR-enhanced core-shell AgD/g-C3N4 composite photocatalysts (AgD-CN) were synthesized by thermal polymerizing mixtures of melamine and different amounts of AgD. This core-shell AgD-CN improved the stability of AgD and made full use of the near-field enhancement effect of AgD’s LSPR, resulting in a broad light absorption band. AgD-CN-15 showed the highest photogenerated electron-hole pair separation rate and the best photocatalytic performance when the addition amount of AgD was 3 wt%. The degradation rate of RhB by AgD-CN-15 reached 95.20% after sunlight irradiation for 60 min, and its reaction rate constant was 5.2 times that of the pristine g-C3N4. Moreover, ·OH, h+ and ·O2- were found to be the main active species. AgD is easy to prepare and can broaden the light absorption wavelength range and significantly enhance light absorption ability of photocatalysts, which provides a new method to improve the performance of LSPR-enhanced photocatalysts.

Enhancing broad-band light and CO gas sensing with BDT/ZnO nanocomposites

Gas/light dual sensors based on benzodithiophene-based derivates (BDT)/zinc oxide (ZnO) nanocomposites are fabricated for the monitoring of hazardous light and the detection of toxic gases. The lethal threat posed by colorless and odorless carbon monoxide (CO) gas, as well as the potential dangers of ultraviolet-A (UV-A) and visible light, emphasize the need for sensitive and portable gas/light dual sensor. Organic BDT/inorganic ZnO hybrid materials have gained attention for their cost-effectiveness, and enhanced gas/light sensing performance. This study explores the incorporation of the organic material, BDT, onto the ZnO nanorods (NRs) to enhance the UV and visible light detection, and CO gas sensing capabilities. The results demonstrate that improved light absorption and gas detection are attributed to the broad absorption wavelength range of BDT and efficient charge transfer from BDT to ZnO NRs. The study introduces a novel approach for dual sensing applications, highlighting the promising future of BDT/ZnO nanocomposites in environmental monitoring and wearable devices.

Facile preparation of high-performance hydrochar/TiO2 heterojunction visible light photocatalyst for treating Cr(VI)-polluted water

In order to remedy the shortcomings of narrow absorption wavelength range and low photogenerated carrier separation efficiency of TiO2 photocatalyst, hydrochar (HC) was chosen to modify TiO2 by constructing HC/TiO2 heterojunction composite. HC/TiO2 composites were synthesized from glucose, tetrabutyl titanate and deionized water by a simple one-pot hydrothermal way, and their photocatalytic Cr(VI) reduction properties were studied. The results indicated that HC/TiO2 composites had tremendously improved photocatalytic Cr(VI) reduction activity, in comparison with TiO2, HC and a number of newly reported TiO2-based visible light photocatalysts. When the mass percentage of glucose to tetrabutyl titanate was 14, the obtained HC/TiO2-2 possessed the maximal photocatalytic activity, which was 19 times that of TiO2 and 14.3 times that of HC under visible light (wavelength > 420 nm) irradiation, and 3.2 times that of TiO2 under ultraviolet-visible light (Xenon lamp) irradiation. Furthermore, the photocatalytic stability of HC/TiO2-2 was also excellent. Additionally, proper choice of the photocatalysis experiment parameters could further raise the photocatalytic Cr(VI) reduction efficiency of HC/TiO2-2. The exceptionally elevated photocatalytic activity of HC/TiO2-2 was found to be due to its type-II heterojunction structure, which drastically heightened the separation and transfer efficiencies of photogenerated electrons and holes. Besides, HC/TiO2-2 also showed great potential for practical application in photocatalytic treatment of the Cr(VI) effluents discharged from freezing brine and black chromium plating industries.

Performance enhancement of CsPbI3-xBrx perovskite solar cells via graded bandgap and affinity engineering

All inorganic cesium lead-based perovskite solar cells (PSCs) have gained attention as alternative absorbing materials owing to their exceptional thermal stability. However, these devices are suffer from transmission and thermalization losses. Therefore, a novel grading approach is used in CsPbI3-x Brx perovskite solar cell to reduce the transmission and thermalization losses by enhancing the cell’s ability to capture a broad spectrum of light wavelengths and suitably accommodate the material’s energy bandgap. In this work, the performance of CsPbI3-xBrx perovskite solar cell with graded bandgap (Eg) and affinity has been explored and analyzed using the simulation SCAPS-1D tool. Different compositions (x) are varied to adjust the bandgap of CsPbI3-xBrx with different grading profiles such as linear, parabolic and beta grading. The graded structure enhances the absorption wavelength range and carrier lifetime. However, it also leads to the redistribution of the electrical field within the device, promoting more effective charge separation and collection. By utilizing this approach, the impact of absorber thickness variations from (50 nm to 700 nm) is also studied and analyzed with respect to grading profiles. Initially, 16.75% power conversion efficiency (PCE) is obtained by calibrating the experimental CsPbI3-xBrx graded solar cell. Then, performance is further improved by adjusting the bandgap with grading profiles, optimizing ETLs/HTLs and achieving optimum PV parameters: short-circuit current density (JSC) of 20.50 mA cm−2, open-circuit voltage (VOC) of 1.35 V, fill factor (FF) of 84.15% and PCE of 23.11%. The findings of the reported study would significantly provide a path for the development of graded PSC.

Near-infrared II fluorescent carbon dots for differential imaging of drug-resistant bacteria and dynamic monitoring of immune system defense against bacterial infection in vivo

In vivo fluorescence imaging allows the accurate acquisition of dynamic biological information, which plays a vital role in the early diagnosis and treatment of bacterial infectious diseases. Herein, a NIR-II-emitting CD-based nanoprobe (CyCDs) is synthesized using Cy7-CH3 as the carbon source and 3-hydroxytyramine hydrochloride as the surface passivator. Notably, the π-conjugated system and rigid planar structure of the carbon source can broaden the wavelength range of absorption and emission. The presence of amino groups enables CyCDs with a positive zeta potential (+0.32 mV), which can facilitate the interactions between CyCDs and bacteria. Interestingly, CyCDs can only stain the cell wall of drug-resistant bacteria, while normal bacteria have a bright fluorescent signal over all of the cell. This phenomenon enables the identification of drug-resistant bacteria in vitro. Furthermore, CyCDs can be used to monitor the interaction between the immune system and infected bacteria in vivo and guide the timely usage of antibiotics

Construction of a Novel TiO2‐Covalent‐Organic‐Framework Heterojunction for Highly Selective Photo‐Oxidation Coupling of Amines under Visible Light Irradiation

AbstractA novel heterojunction material constructed with titanium dioxide nanoparticles and covalent organic frameworks, TiO2@COF‐5 NPs, was designed and synthesized successfully from HHTP, PBBA and TiO2 under solvothermal conditions. Notably, the TiO2@COF‐5 heterojunction demonstrated excellent photocatalytic performance for the aerobic oxidative coupling reaction of benzylamines to N‐benzyl‐1‐phenyl methanimines under visible light irradiation, and both high conversions (up to 99 %) and high selectivity (99 %) were achieved for various benzylamines. The ameliorated photocatalytic performance might owe much to establishing the systematic coupling between the TiO2 nanoparticles and covalent organic frameworks, which could effectively extend the wavelength range of visible light absorption and increase more reactive active sites. This study might provide a versatile approach to combining covalent organic frameworks with inorganic semiconductors to give full play to the synergistic effect of catalysis.

Development of structural colored TiO2 thin films by varied etching solutions

Currently, one of the most important problems is water scarcity due to increasing population and environmental factors. Humankind can overcome this problem by recycling polluted water. The structural colors obtained from photonic crystal structures draw attention with fadeless bright color, combined with low toxicity and eco-friendliness. In this study, different etching/anodizing processes were applied to obtain Fabry-Perot and Photonic Crystal Ti-TiO2 structures. Structural colors owing to the morphology of the anatase phase on the surface of the samples etched with hydrochloric, sulfuric, and hydrofluoric acid-based solutions were obtained. The structural color of the formation on the titanium surfaces is related to the Fabry-Perot structures, while variations were correlated with Photonic Crystal surface morphologies. Because the high reflectance values contributed to the structural color formation, the photocatalytic efficiency of the samples etched with acid-based solutions was found to be lower than the samples etched with basic sodium and potassium hydroxide solutions. High-efficiency structural color reactors can be obtained by shifting the reflected wavelength range from the absorption wavelength range of the pollution material.

Efficient photocatalytic hydrogen evolution reaction promoted via a synergistic strategy of S-scheme heterojunction structure combined with surface plasmon resonance effect

Photocatalysis has great potential for the utilization of solar energy, which depends on the design and preparation of an efficient photocatalyst. The recent design of S-scheme heterojunction is expected to enhance the redox ability and accelerate electron separation and migration. To further promote the charge transfer and broaden light absorption in the heterostructure, we proposed a strategic merging with the surface plasmon resonance (SPR) effect. In this work, the (C and O) co-doped g-C3N4 (COCN) was in-situ combined with W18O49 to construct the S-scheme heterojunction termed COCN-W18O49. Co-doping of C and O atoms leads to a change in the band structure of COCN, the formation of surface defects, and an enhancement in carriers concentration. The W18O49 possesses plentiful W5+ defects and oxygen vacancies, which can produce hot electrons to accelerate the separation of carriers and broaden the wavelength range of light absorption by the SPR effect. Furthermore, the S-scheme heterojunction effectively utilizes the reduction and oxidation units of COCN and W18O49, respectively, and the presence of an internal electric field with direction from COCN to W18O49 accelerates electron transfer. As a result, the novel S-scheme COCN-W18O49 heterojunction can achieve a superior photocatalytic degradation performance that is 4.25 times as high as GCN, 2.3 times as high as COCN, and 1.6 times as high as W18O49. At the same time, the hydrogen evolution performance of the COCN-W18O49 composite was also 11.9 times as high as GCN and 1.8 times as high as COCN, while W18O49 was unable to hydrogen evolution. This work provides a new pathway for designing S-scheme heterojunction with swift interfacial electron flows, which has great potential for hydrogen evolution and wastewater treatment applications.

Ultra-thin Ag/Si heterojunction hot-carrier photovoltaic conversion Schottky devices for harvesting solar energy at wavelength above 1.1 µm

Traditional silicon solar cells can only absorb the solar spectrum at wavelengths below 1.1 μm. Here we proposed a breakthrough in harvesting solar energy below Si bandgap through conversion of hot carriers generated in the metal into a current using an energy barrier at the metal–semiconductor junction. Under appropriate conditions, the photo-excited hot carriers can quickly pass through the energy barrier and lead to photocurrent, maximizing the use of excitation energy and reducing waste heat consumption. Compared with conventional silicon solar cells, hot-carrier photovoltaic conversion Schottky device has better absorption and conversion efficiency for an infrared regime above 1.1 μm, expands the absorption wavelength range of silicon-based solar cells, makes more effective use of the entire solar spectrum, and further improves the photovoltaic performance of metal–silicon interface components by controlling the evaporation rate, deposition thickness, and annealing temperature of the metal layer. Finally, the conversion efficiency 3.316% is achieved under the infrared regime with a wavelength of more than 1100 nm and an irradiance of 13.85 mW/cm2.

An effective strategy of indium half-doping to stabilize the structure and improve optoelectronic characteristics of Tl-Co based double perovskite: First principles study

Doping can improve the structural stability and photoelectric properties of perovskite materials. In this study, indium element was added into Tl-Co double based perovskite material to stabilize its structure and improve its photoelectric performance. The results show that the doped material Cs2In0.5Tl0.5CoX6(X = I, Br, Cl) has better ductility and stability than the original Cs2TlCoI6 by elastic constants and phonon spectra. Moreover, indium doping can improve the band structure of Tl-Co double-base perovskite materials, such as changing the band value to the optimal band gap value of solar energy absorber and transforming from indirect band structure to quasi-direct band structure. In terms of optical properties, indium doping can expand the wavelength range of the material's light absorption, making its absorption spectrum more matching with the simulated AM1.5 spectrum. Cs2In0.5Tl0.5CoCl6 is proposed to be a promising candidate for optoelectronic applications based on its structural stability, bandgap value and optical absorption spectrum.