Carrier Lifetime Research Articles

Investigation of physical and electrical properties of a suboxide layer at Si/Si-hexafluoride interface

The silicon suboxide SiOx (x < 2.0) offers promising industrial application possibilities ranging from electrodes in lithium-ion batteries, which are used widely in electrical vehicles and portable devices to sensing applications. Therefore, a low cost, environmental friendly and high performance silicon oxide materials are required for an appropriate operation of any electronic gadget. In this work, we report on the physical and electrical properties of a suboxide layer of up to 1 μm, which was grown on silicon during the formation of a dielectric layer, namely the ammonium silicon hexafluoride. It is a stable oxide exhibiting light emission from 400 to 1700 nm offering scalable and cost-effective large area processing capability. The measurement results reveal interesting properties, which are required to be understood clearly before proceeding with any suitable application. The results have been analyzed using state-of-the-art physical and electrical characterization techniques such as ellipsometry, AFM, SEM, FTIR, photoluminescence lifetime and resistive switching measurements to determine structural, optical and electrical properties. At 300 K the carrier lifetime measurements reveal the lifetime values ranging from about few tens of picosecond up to 4500 picoseconds. Scanning probe analysis indicate a surface roughness of about 30 Å. Resistive memory forming was observed also in these layers at relatively low power thresholds. We provide a comprehensive description of the physical and electrical properties in order to clarify the origin of the observed features. The wavelength dependent real ε1(ω)\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\varepsilon }_{1}(\\omega )$$\\end{document} and the imaginary ε2ω\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\varepsilon }_{2}\\left(\\omega \\right)$$\\end{document} dielectric functions provided useful insights on optical properties. A lookout is given for the possible applications of this special SiOx dielectric oxide layer.

Effective Lifetime of Nonequilibrium Carriers in Perovskite‐Inspired Cu2AgBiI6

Perovskite‐inspired materials (PIMs) are potential alternatives to lead halide perovskites, as they not only inherit the benign optoelectronic properties but also diminish the stability and toxicity issues of lead halide perovskites. As a newly discovered PIM, Cu2AgBiI6 has exhibited promising potential for photovoltaic applications. However, studies on its fundamental properties related to photovoltaic performance are scarce, particularly from a theoretical perspective. Herein, the effective lifetime of nonequilibrium carriers (photo‐excited charge carriers) is systematically investigated, a critical property affecting the photovoltaic performance of Cu2AgBiI6, based on the nonadiabatic molecular dynamics simulations. It is found that under the standard solar spectrum illumination, the dominant recombination mechanism affecting the effective lifetime can be band‐to‐band nonradiative decay, band‐to‐band radiative decay, or Shockey–Read–Hall defect‐assisted decay. The specific mechanism is highly dependent on the radiative recombination coefficient and the density of defect recombination levels. The effective lifetime can vary from 0.1 ms to 10 ns. When considering different illumination conditions (generation rates), Auger decay can also become the dominant recombination mechanism, with the effective lifetime varying from 0.1 s to 0.1 ns. These findings can be vital for further experimental researches aimed at enhancing the power conversion efficiency of Cu2AgBiI6‐based solar devices.

Construction of novel Ce2(WO4)3/rGO nanocomposites for efficient photocatalytic mitigation of antibiotic drug chloramphenicol

In this study, we present the synthesis and characterization of a novel cerium tungstate decorated reduced graphene oxide (Ce2(WO4)3@rGO or CeW@rGO) nanocomposite via a facile hydrothermal method. Comprehensive analyses including XRD, FTIR, SEM, TEM, and XPS were conducted to elucidate the crystal structure, chemical states, morphology, and optical properties of the synthesized nanocomposite. The CeW@rGO exhibited a reduced band gap of 2.14 eV compared to 2.33 eV for CeW, enhancing visible light absorption. Photocatalytic experiments demonstrated the superior efficiency of CeW@rGO, achieving 98.03 % degradation of the antibiotic chloramphenicol (CIP) within 45 min under visible light irradiation. The enhanced photocatalytic performance is attributed to the improved charge separation and extended lifetime of photo-induced charge carriers, facilitated by the rGO. Reactive oxidative species such as O2•− and •OH were identified as key contributors to the degradation process, as confirmed by radical scavenging studies. The plausible degradation mechanism of CIP was proposed based on LC-MS analysis. This work highlights the potential of CeW@rGO as an efficient and sustainable photocatalyst for environmental remediation, offering significant advancements in the field of photocatalytic degradation of organic contaminants. The improved efficiency of the photocatalyst was primarily due to the enlarged surface area and the addition of CeW and rGO to the composite sample. These additions enhance the catalyst's ability to adsorb pollutants and increase the separation of electrons and holes at the interface between two semiconductors by creating an internal electric field. The results toprovide the successfully creation ofCeW/rGO nanocomposites that are cost-effective, highly efficient, lightweight, and sustainable for use in environmental applications.

Effect of Gamma Irradiation on Electrophysical Parameters of Silicon Solar Cells Doped with Nickel

The results of the studies of changes in the electro-physical parameters (Voc – no-load voltage, Isc – short-circuit current density; τ – lifetime of nonequilibrium charge carriers) of photocells made on plates of monocrystalline silicon of the p-type conductivity with the specific resistance ρ 0.5 Ohm cm, doped with nickel, under irradiation with γ-quanta from 60Co source are presented. It is shown that the efficiency of the solar energy conversion in nickel-doped photovoltaic cells remains higher than in standard cells up to irradiation doses of 108 rad. It was established that with increasing diffusion temperature of nickel atoms radiation stability of electrophysical parameters of photovoltaic cells also increases. A decrease in the concentration of recombination-active radiation defects is due to the getterization by nickel atoms of technological (background) impurities and the action of nickel clusters as effluents for radiation-induced vacancies.

Enhanced structural and optical properties of Cs0.1FA0.9PbI3 perovskite thin film with potassium doping for perovskite solar cells

Hybrid halide perovskite (HHP) materials have been rigorously explored since last decade specially for their potential use as absorber layer material in perovskite solar cells. Formamidinium (FA) based HHP materials show many fascinating properties and exhibit thermal stability. However, photoactive cubic phase of formamidinium lead iodide (FAPbI3) material is unstable at room temperature. To overcome the phase stability issue, substitution of Cs+ or MA+ (methylamine) ion has been found useful. Further, to enhance the material properties of FA-MA or FA-Cs based HHP materials, alkali ion doping is widely explored. In this study, the role of K+ ion doping in enhancing the optoelectronic properties of Cs-FA based HHP material is studied thoroughly by structural and optical characterizations. The XRD results show the suppression of yellow non-perovskite phase after Cs doping in FAPbI3 material. The SEM results predict increased grain size with small K+ content in Cs0.1FA0.9PbI3 material. The PL and TRPL results predict the increase in radiative recombination and charge carrier lifetime with small K-doping and detrimental effects of doping concentration above 3 % of K. The solar cell simulation results yield a maximum power conversion efficiency of 18.21 % in K0.03(Cs0.1FA0.9)0.97PbI3 absorbing layer-based device.

Synergistic effect between ohmic contacts and localized surface plasmon resonance for enhancing CO2 photoreduction of BiOBr

The fast recombination rate of photogenerated carrier and short electron lifetime are the main factors affecting the CO2 reduction performance of BiOBr (BOB). The utilization of ohmic contacts and the localised surface plasmon resonance (LSPR) effect of metals can effectively solve the above problems. However, one mean alone is not ideal for improving the photocatalytic performance of BOB. Therefore, in this work, we reduced the metal Bi to the surface of BOB in an attempt to form a synergistic effect of ohmic contact and LSPR effect. DFT calculations confirm the ohmic contact between Bi and BOB. Meanwhile, electrochemical tests show that Bi/BOB-2 has a higher photocurrent density (1.1 μA/cm2), suggesting that the ohmic contact achieves ultrafast electron transfer from BOB to Bi under light. While the UV–Vis diffuse reflectance spectroscopy results show resonance absorption peaks from the LSPR effect of Bi, the TRPL results show that Bi/BOB-2 has a longer τave (3.05 ns), implying that longer-lived hot electrons are generated on the Bi surface. The synergistic effect of the two contributes to the efficient CO2 to CO transition on the catalyst surface. As a result, Bi/BOB-2 exhibites a 4.37-fold higher CO generation rate (11.45 μmolg-1 h−1) than that of pure BOB (2.62 μmolg-1 h−1) under light. This study provides a new blueprint for the design of BiOBr-based materials for efficient photocatalytic reduction of CO2.

Compression of Organic Molecules Coupled with Hydrogen Bonding Extends the Charge Carrier Lifetime in BA2SnI4.

Two-dimensional (2D) metal halide perovskites, such as BA2SnI4 (BA═CH3(CH2)3NH3), exhibit an enhanced charge carrier lifetime in experiments under strain. Experiments suggest that significant compression of the BA molecule, rather than of the inorganic lattice, contributes to this enhancement. To elucidate the underlying physical mechanism, we apply a moderate compressive strain to the entire system and subsequently introduce significant compression to the BA molecules. We then perform ab initio nonadiabatic molecular dynamics simulations of nonradiative electron-hole recombination. We observe that the overall lattice compression reduces atomic motions and decreases nonadiabatic coupling, thereby delaying electron-hole recombination. Additionally, compression of the BA molecules enhances hydrogen bonding between the BA molecules and iodine atoms, which lengthens the Sn-I bonds, distorts the [SnI6]4- octahedra, and suppresses atomic motions further, thus reducing nonadiabatic coupling. Also, the elongated Sn-I bonds and weakened antibonding interactions increase the band gap. Altogether, the compression delays the nonradiative electron-hole recombination by more than a factor of 3. Our simulations provide new and valuable physical insights into how compressive strain, accommodated primarily by the organic ligands, positively influences the optoelectronic properties of 2D layered halide perovskites, offering a promising pathway for further performance improvements.

Red-Emitting CsPbI3/ZnSe Colloidal Nanoheterostructures with Enhanced Optical Properties and Stability.

Producing heterostructures of cesium lead halide perovskites and metal-chalcogenides in the form of colloidal nanocrystals can improve their optical features and stability, and also govern the recombination of charge carriers. Herein, the synthesis of red-emitting CsPbI3/ZnSe nanoheterostructures is reported via an insitu hot injection method, which provides the crystallization conditions for both components, subsequently leading to heteroepitaxial growth. Steady-state absorption and photoluminescence studies alongside X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy analysis evidence on a type-I band alignment for CsPbI3/ZnSe nanoheterostructures, which exhibit photoluminescence quantum yield of 96% due to the effective passivation of surface defects, and an enhancement in carrier lifetime. Furthermore, the heterostructure growth of ZnSe domains leads to significant improvement in the stability of the CsPbI3 nanocrystals under ambient conditions and against thermal and UV irradiation stress.

Tuning of interface quality of Al/CeO2/Si device by post-annealing of sol-gel grown high-k CeO2 layers

A comprehensive study has been done on the influence of post-deposition annealing temperature on high-k cerium oxide (CeO2) layer grown on n-type silicon (Si) substrate and its resultant interface states have been studied for Al/CeO2/Si metal-oxide-semiconductor (MOS) devices. The high-k CeO2 thin films were deposited by spin-coating and sintered at different annealing temperatures (Ta) in the range of 400–900 °C. The parameters such as fixed charge density (Qeff), dielectric constant (k) of the layers, flat-band voltage (VFB), interface defect density (Dit), etc., of the MOS device were evaluated from CV and I-V measurements. A minimum value of flat band shift (∼0.05 V) with lower Qeff (−4.81 × 1011 C/cm2) have been achieved for the Ta of 600 °C. The k and Dit were evaluated to be 22 and 1.29 × 1012 cm−2, respectively at the Ta of 600 °C. In addition, the CV measurements showed a very small hysteresis and very low frequency dispersion for the Ta of 600 °C sample. Energy distribution of defect states was evaluated and it was maximum towards the bottom of the conduction band. This shows that the 600 °C is the optimum annealing temperature, which results in high quality interface, and the electron affinity of the corresponding CeO2 layers was found to be 3.29 eV as evaluated from ultraviolet photoelectron spectroscopy (UPS). Further, a maximum value of minority carrier lifetime (147 μs) has been achieved for the samples annealed at Ta of 400 °C, indicating that the post-annealing temperature plays a significant role on the properties of CeO2 films deposited by sol-gel process. Thus, the present study demonstrates the possibility of sol-gel grown high k-CeO2 layers suitable for MOS like devices.

Low temperature method-based evaporation/spray-coating technology for wide bandgap perovskite solar cells

Years of working on perovskite solar cells (PSCs)-based tandem devices and single-junction devices have approved that low annealing temperatures can be beneficial for improving device performances. In this study, pseudo-halogen ion engineering works well in the evaporation/spray-coating method. According to our research, it is has been proven that the addition of formamidine acetate (FAAc) can effectively reduce the annealing temperature from 170 °C to 150 °C, accelerate the maturation process of the perovskite films, and broaden the annealing window. As a result, a perovskite film with homogeneous crystallization and low residual stress is achieved, leading to extended charge carrier lifetimes, elevated photoluminescence quantum yields (PLQY), reduced Urbach energies. The corresponding PSCs were prepared through evaporation/spray-coating method achieves an impressive power conversion efficiency (PCE) of 19.46%, which is the highest efficiency among wide-bandgap (WBG) PSCs fabricated by this method. And the unencapsulated devices exhibit satisfactory stability, retaining 80% of the initial PCE after 600 h of thermal aging at 60 °C and retaining 90% of the initial PCE after 1500 h of 50% humidity aging at 25 °C, respectively.

Understanding the Strong Apparent Injection Dependence of Carrier Lifetimes in Doped Polycrystalline Silicon Passivated Wafers

This study investigates the injection dependence of carrier lifetimes of p‐ and n‐type samples passivated by doped‐polycrystalline silicon (poly‐Si) (p+ and n+ poly‐Si) contacts. A strong apparent injection dependence of the carrier lifetimes is observed in p‐n junction samples (p+ poly‐Si on n‐type or n+ poly‐Si on p‐type) but no injection dependence is observed in high‐low junction samples (p+ poly‐Si on p‐type or n+ poly‐Si on n‐type). Further, photoluminescence images captured at two illumination intensities of 0.05 and 0.87 suns reveal that edge recombination contributed the strong apparent injection dependence in p‐n junction samples. Furthermore, this apparent injection dependence increases as the sample size is reduced, and as the sheet resistance of the doped poly‐Si contacts is decreased, allowing more effective transport of minority carriers to the recombination‐active edge regions.

Shifting the Paradigm: A Functional Hole‐Selective Transport Layer for Chalcopyrite Solar Cells

High‐efficiency Cu(In,Ga)Se2 solar cells rely on Ga grading to mitigate back surface recombination. However, the inhomogeneous absorber has drawbacks, including increased non‐radiative loss and inadequate absorption. Therefore, literatures demand a paradigm shift of using a hole‐transport layer to passivate the back surface. Herein, a functional hole‐transport layer is demonstrated as an alternative to Ga grading. The novel hole‐transport layer is prepared as a double‐layer: co‐evaporated CuGaSe2 covered by solution combustion synthesis prepared In2O3. As demonstrated by micrographs, elemental mapping, and photoluminescence spectroscopy, the oxide layer improves thermal stability and prevents Ga diffusion. However, during the absorber deposition, a complete ion exchange of In and Ga converts CuGaSe2/In2O3 into CuInSe2/GaOx. Incorporating this hole‐transport layer in co‐evaporated nongraded CuInSe2 solar cells leads to significantly increased minority carrier lifetime from 5 to 113 ns, yielding an 80 meV improvement in quasi‐Fermi‐level splitting. The devices exhibit improved open‐circuit voltage, as well as a promising fill factor of over 71%, indicating good hole‐transport properties. In these results, the passivation effect and good hole‐transport properties of the hole‐transport layer are experimentally demonstrated. Thus, high‐efficiency solar cells can be achieved by using a functional hole‐transport layer without relying on Ga grading.

Influence of growth temperature on structural, optical, morphological and photoelectrochemical characteristics of vertically aligned hydrothermally synthesized TiO2 nanorods

Herein, vertically oriented TiO2 nanorods were prepared on FTO substrate using hydrothermal synthesis. The influence of growth temperature on structural, optical, morphological and photoelectrochemical characteristics were analyzed. The FESEM and AFM results validated the formation of TiO2 nanorods. XRD spectra revealed the formation TiO2 tetragonal crystal structure with the rutile phase. UV–vis data showed an increase in the visible light absorption and a narrowing of the energy band gap with increasing in reaction temperature. Based on PEC studies, all the samples showed good light response and pronounced photocurrent density under light conditions. The highest possible photocurrent density of 78.8 μA/cm2 at 1.2V vs Ag/AgCl was recorded from TiO2 film with hydrothermal growth temperature of 200°C for 3 h s. This performance is attributed to narrow bandgap (2.89eV) and longer lifetime of carriers (0.3s). This result was validated by data from EIS, whereby the fast separation and transfer of photogenerated charge carriers were demonstrated.

Photovoltaic Cell Prepared from Nanoparticles of CdS/CdTe on ITO Substrate and its Characterization

CdS/CdTe based photovoltaic cell has shown the markable efficiency. The CdS/CdTe nanoparticles are being synthesized and deposited on the ITO glass plate. ITO glass has a large bandgap of about approximately 3.6 eV and is suitable to use in the fabrication of photovoltaic cell. As ITO behaves as negative terminal, it is used as front layer for capturing the light intensity. During fabrication of photovoltaic cell, the deposition of Cadmium sulphide and Cadmium telluride nanoparticles layer was done by brush painting technique. The CdS layer is used as window layer and CdTe acts as absorbing layer. The window layer’s primary function is to absorb light particularly in the visible region of the spectrum to generate electricity. The CdS layer forms p-n junction with the CdTe layer. The nanoparticles of CdS and CdTe have been synthesized first and optical characterization was carried out using UV-visible spectroscopy to obtain bandgap of CdTe and CdS. Structural characterization was being obtained by XRD. The size of the nanocrystallites of CdS and CdTe have been obtained by Debye Scherrer equation and the result was 1.64 nm and 4.09 nm respectively. The CdTe layer which was used as absorbing layer consists of high optical absorption coefficient with high mobility, good carrier lifetime and an enhanced properties of crystallographic. Silver paste was used as a back contact for good conduction.

Pyridine substitution strategy for one-dimensional perovskite: Toward efficient and stable mixed-dimensional photovoltaics

Surface passivation via one-dimensional (1D) perovskite has emerged as a promising method to suppress trap states and enhance charge extraction and transportation, leading to improved efficiency and long-term stability. Ionic liquid engineering, characterized as environmental-green additive, has shown particular promise in this regard. Herein, we explore the influence of the electronegativity and dipole moment of two different ionic liquids, benzamidine hydrochloride (BZ) and 2-amidinopyridine hydrochloride (2AP), on the formation of 1D perovskite and the performance of resulting devices. An effective passivation 1D layer has been formed through post-treatment, resulting in nano-rod crystal modified morphology with effectively passivated defects at grain boundaries, enhanced hydrophobicity, prolonged charge carrier lifetime, tailored energy level, and decreased trap density. Notably, the perovskite film treated with 2AP exhibited superior performance due to its stronger interaction with 3D perovskite and better passivation ability on defects originating from the presence of a pyridine ring. As a result, the PSCs incorporating 2AP achieved a champion power conversion efficiency of 24.55 % and retain 90 % of their initial efficiency after storage for over 1000 h at room temperature under ∼ 50 % RH conditions without encapsulation. This study provides valuable insights for expanding the selection of ionic liquids applied in 1D perovskite-assisted surface passivation towards efficient and stable photovoltaics.

Delocalizing Excitation for Highly-Active Organic Photovoltaic Catalysts.

Localized excitation in traditional organic photocatalysts typically prevents the generation and extraction of photo-induced free charge carriers, limiting their activity enhancement under illumination. Here, we enhance delocalized photoexcitation of small molecular photovoltaic catalysts by weakening their electron-phonon coupling via rational fluoro-substitution. The optimized 2FBP-4F catalyst we develop here exhibits a minimized Huang-Rhys factor of 0.35 in solution, high dielectric constant and strong crystallization in the solid state. As a result, the energy barrier for exciton dissociation is decreased, and more importantly, polarons are unusually observed in 2FBP-4F nanoparticles (NPs). With the increased hole transfer efficiency and prolonged charge carrier lifetime highly related to enhanced exciton delocalization, the PM6 : 2FBP-4F heterojunction NPs at varied concentration exhibit much higher optimized photocatalytic activity (207.6-561.8 mmol h-1 g-1) for hydrogen evolution than the control PM6 : BP-4F and PM6 : 2FBP-6F NPs, as well as other reported photocatalysts under simulated solar light (AM 1.5G, 100 mW cm-2).

Study of Fabrication Process and Performance Analysis of the CDS/CDTE Based Photovoltaic Cell

Fabrication of CDS/CDTE based heterojunction photovoltaic cell has been undertaken to explore better light conversion efficiency. We have developed a photovoltaic cell using glass coated with Indium doped Tin Oxide (ITO) which works as transparent conducting oxide (TCO). ITO coated glass has promising prospects of enhancing the efficiency of the photovoltaic cell. ITO layers are known to be employed as anode terminal due to the negative polarity they possess compared to the whole PV cell; here, we have employed it for the same function as the front layer. During fabrication of the photovoltaic cell, the deposition of nanoparticles of CDS and CDTE layer is undertaken through doctor-blade method. We have employed pure CDS as window layer for its high band gap of 3.8 eV (particle size: 8 nm) and CDTE as absorber layer due to its high optical absorption coefficient with high mobility, good carrier lifetime and enhanced crystallographic properties. The CDS window layer and CDTE absorber layer together constitute a p-n junction where the CDS window layer captures high intensity photons and transmits the photo-excited electron to CDTE absorber layer, thereby leading to photo-current output, which serves as a base to explore and test its further applications. To obtain band gap of respective CDTE and CDS nanoparticles, optical characterization is used. Silver paste is used as rear contact to form anode terminal having good conductivity and providing better mechanical support to the photovoltaic cell.

Delocalizing Excitation for Highly‐Active Organic Photovoltaic Catalysts

AbstractLocalized excitation in traditional organic photocatalysts typically prevents the generation and extraction of photo‐induced free charge carriers, limiting their activity enhancement under illumination. Here, we enhance delocalized photoexcitation of small molecular photovoltaic catalysts by weakening their electron‐phonon coupling via rational fluoro‐substitution. The optimized 2FBP‐4F catalyst we develop here exhibits a minimized Huang–Rhys factor of 0.35 in solution, high dielectric constant and strong crystallization in the solid state. As a result, the energy barrier for exciton dissociation is decreased, and more importantly, polarons are unusually observed in 2FBP‐4F nanoparticles (NPs). With the increased hole transfer efficiency and prolonged charge carrier lifetime highly related to enhanced exciton delocalization, the PM6 : 2FBP‐4F heterojunction NPs at varied concentration exhibit much higher optimized photocatalytic activity (207.6–561.8 mmol h−1 g−1) for hydrogen evolution than the control PM6 : BP‐4F and PM6 : 2FBP‐6F NPs, as well as other reported photocatalysts under simulated solar light (AM 1.5G, 100 mW cm−2).

Synthesis of Fe-Modified g-C3N4 Nanorod Bunches for the Efficient Photocatalytic Degradation of Oxytetracycline.

Antibiotic residues have been found to have potentially harmful effects on ecological and human health. Carbon nitride-based photocatalysts have widely focused on antibiotic photocatalytic degradation. Herein, we prepared Fe-modified g-C3N4 nanorod bunches (FCNBs) using chemical vapor co-deposition. Specifically, through the process of calcination, a blend of urea and chlorophyllin sodium iron salt underwent an intriguing transformation, resulting in the integration of Fe into the framework of the g-C3N4 nanorod cluster. The resulting photocatalyst exhibited remarkable stability and superior dispersibility. The prepared FCNBs had a unique structure, which was beneficial for increasing light absorption. Furthermore, the Fe species formed a chemical coordination with the g-C3N4 matrix, thereby altering the electronic structure of the matrix. This modification facilitated charge transfer, prolonged the carrier lifetime, and enhanced light absorption, all of which significantly increased the photocatalytic activity. The oxytetracycline degradation efficiency of FCNBs was 82.5%, and they demonstrated outstanding stability in cycle trials. This work introduces a promising photocatalyst for the degradation of antibiotics.

Increasing terminal alkyl chain length for a better small molecule organic solar cell donor

Optimizing the alkyl chains within a terminal group is considered to be a highly effective approach for boosting the power conversion efficiency (PCE) of all small-molecule organic solar cells (ASM-OSCs). In this study, we focus on designing and synthesizing small molecular (SM) donor compounds with different end-group alkyl chain lengths to study their impact on OSC performance. Under optimized conditions, OSC devices based on BTR-Cl-C8:Y6 demonstrate higher PCE of 14.43 % compared to those based on BTR-Cl:Y6. Moreover, BTR-Cl-C8 exhibits reduced levels of bimolecular recombination and trap-assisted recombination, enhanced capability for exciton dissociation and charge collection, and extended carrier lifetimes. These results highlight the significance of molecular design strategies in optimizing OSC performance and offer valuable insights for the development of efficient and stable ASM-OSCs.