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Antimony sulfide-selenide, Sb2(SxSe1−x)3 (0 < x < 1), with a tunable bandgap combining the advantages of antimony sulfide (Sb2S3) and antimony selenide (Sb2Se3), shows great potential as a promising light-absorbing material in low-cost, low-toxic, and high-stability thin-film solar cells. In this work, high-quality Sb2(SxSe1−x)3 thin films were successfully prepared by pulsed laser deposition (PLD) using the Sb2(SxSe1−x)3 compound targets for the first time and realized tunable bandgaps by simply changing the S/(Se + S) ratios of compound targets. The effects of substrate temperature and S/(S + Se) ratio on the structural, morphological, and optical properties of films were investigated separately. It was discovered that 500 °C was the optimum substrate temperature to grow high-crystallinity, good-morphology, and low-defects Sb2(SxSe1−x)3 thin films, and the film with S/(S + Se) ratio of 0.2 showed optimal properties. Optical characterization demonstrated all Sb2(SxSe1−x)3 thin films owned high absorption coefficients above 105 cm−1 at the visible light region and suitable bandgaps near the ideal value of the Shockley–Queisser limit. The results of energy dispersive spectrometer showed that all films were poor in Sb and rich in (S + Se), which was a favorable condition for them as light absorbers. The activation energy obtained from the electrical measurement revealed that the conductivity of Sb2(SxSe1−x)3 thin films was mainly contributed by the intrinsic thermal excitation at 350–500 K. Our research offered a simple and reliable technology to prepare Sb2(SxSe1−x)3 thin films with adjustable bandgaps and favorable properties, which is expected to promote the development and application of this semiconducting material in thin-film solar cells. [ABSTRACT FROM AUTHOR]

In this work, CdTe polycrystalline thin film was deposited on p-type monocrystalline Si substrate via magnetron sputtering technology without an oxygen portion using a well-designed post-processing method under N2:O2 = 4:1, and then CdTe films were etched on the Si surface by Br2-CH3OH solution to analyze the surface and interfacial characteristics of CdTe/Si such as structure, morphology, optics interdiffusion, and intermediate compounds. X-ray diffraction (XRD) results indicate that the polycrystalline CdTe grow preferentially in the (111) direction, and Raman data demonstrate that the CdTe thin film is rich in tellurium, meaning that CdTe, as a p-type semiconductor material, combined with p-Si to form a composite structure. Meanwhile, photoluminescence (PL) spectra suggest that p-CdTe/p-Si under high thermal processing can effectively remove ~1.40 eV defect level, which indicates that the CdTe layer has a lower recombination center. It is particularly worth mentioning that x-ray photoelectron spectroscopy (XPS), XRD, and Raman analysis confirm the Te–Si intermediate compounds at the CdTe/Si interface, which is very conducive to optimizing the contact characteristics of CdTe/Si, thereby improving the interfacial properties of CdTe/Si. This work reveals a potentially effective way to improve the performance of photoelectric devices by introducing poly-CdTe/Si as a composite structure. [ABSTRACT FROM AUTHOR]

The relatively poor selectivity of electrospun nanofiber membrane (ENM) substrate supported thin film composite forward osmosis (eTFC-FO) membranes has hindered their applications. In this study, to overcome the high roughness and large pore size of ENM substrate, a smooth and hydrophilic polydopamine (PDA) interlayer was fabricated on a polyvinylidene fluoride (PVDF) ENM, which was found to be favourable for the formation of a thinner, more cross-linked and less defective polyamide (PA) active layer on the ENM substrate. Desalination tests proved the great effectiveness of PDA interlayer on performance improvement for the eTFC-FO membrane. A quite high water flux (43.0 LMH) and ions rejection (>97.0%) were achieved for a real desulfurization wastewater desalination tested in FO mode. The alleviated PA defects by the PDA interlayer could greatly improve the selectivity. As a comparison with PDA interlayer, PDA coating on each individual nanofiber inside the PVDF ENM substrate was also prepared for eTFC-FO membrane, which would not overcome the disadvantages of rough and large pore sized ENM substrate for PA preparation. Mechanisms of PA formation and performance improvement were detailly discussed in this work. [Display omitted] • Polydopamine (PDA) interlayer was prepared on rough & hydrophobic PVDF nanofibers. • PDA interlayer facilitates the formation of thinner and more cross-linked PA layer. • Interlayer can alleviate PA defect and improve selectivity of eTFC-FO membrane. • eTFC-FO with interlayer enhanced performance for high salinity water desalination. [ABSTRACT FROM AUTHOR]

To address the growing and urgent need for quick and accurate food spoilage detection systems as well as to reduce food resource wastage, recent research has focused on intelligent bio-labels using pH indicators. Accordingly, we developed a dual-channel intelligent label with colorimetric and fluorescent capabilities using black lycium anthocyanin (BLA) and 9,10-bis(2,2-dipyridylvinyl) anthracene (DSA4P) as colorimetric and fluorescent indicators within a composite film consisting of chitosan (Cs), whey protein (Wp), and sodium tripolyphosphate (STPP). The addition of STPP as a cross-linking agent significantly improved the hydrophobicity, mechanical properties, and thermal stability of the Cs/Wp composite films under low pH conditions. After the incorporation of BLA and DSA4P, the resulting dual-channel intelligent label (Cs/Wp/STPP/BLA/DSA4P) exhibited superior hydrophobicity, as indicated by a water contact angle of 78.03°. Additionally, it displayed enhanced mechanical properties, with a tensile strength (TS) of 3.04 MPa and an elongation at break (EAB) of 81.07 %, while maintaining a low transmittance of 28.48 % at 600 nm. After 25 days of burial in soil, the label was significantly degraded, which showcases its eco-friendly nature. Moreover, the label could visually detect color changes indicating volatile ammonia concentrations (25–25,000 ppm). The color of the label in daylight gradually shifted from brick-red to light-red, brownish-yellow, and finally light-green as the ammonia concentration increased. Correspondingly, its fluorescence transitioned from no fluorescence to green fluorescence with increasing ammonia concentration, gradually intensifying under 365-nm UV light. Furthermore, the label effectively monitored the freshness of shrimp stored at temperatures of 4 °C, 25 °C, and − 18 °C. Thus, the label developed in this study exhibits significant potential for enhancing food safety monitoring. [Display omitted] • A colorimetric and fluorescent dual-channel label was developed. • DSA4P is a new pH-sensitive fluorescent molecule for solid film systems. • Black lycium anthocyanins exhibit robust color responsiveness. • The label containing sodium tripolyphosphate had excellent mechanical properties. • The dual-channel intelligent label was exhibited high sensitivity to biogenic amine. [ABSTRACT FROM AUTHOR]

The traditional sol-gel process usually takes a long time to form a stable Cu 2 ZnSnS 4 (CZTS) sol-gel solution, which increases the whole process time. In this paper, an electrodeposition assisted sol-gel process was employed to reduce the solution preparation time. Cu was electrodeposited on Mo surface and ZnSnS sol-gel was rotated on Cu surface to prepare CZTS films. The solution preparation time was reduced from 12h to 30min. The mechanism of CZTS phase formation with sol-gel method assisted by electrodeposition was studied. Cu 3 SnS 4 phase was formed during the electrodeposition assisted sol-gel process, while Cu 2 SnS 3 phase was formed when the CZTS precursor during sol-gel process. Cu content was rich at the beginning of the reaction to form Cu 3 SnS 4 during the electrodeposited assisted sol-gel process. CZTS films with Cu/(Zn + Sn) of 0.84 and Zn/Sn of 1.03 were prepared by sol-gel method assisted by electrodeposition. Compared with CZTS films prepared by sol-gel method, CZTS films prepared by this method have larger and more uniform grains. It is also found that the thickness of MoS 2 layer was thinner than the one prepared by sol-gel method. • An electrodeposition assisted sol-gel method was employed to prepare CZTS films. • The solution preparation time was reduced from overnight to 30min. • The grains of CZTS films prepared by this method were larger and more uniform than the one prepared by sol-gel method. • Electrodeposited Cu helped to suppress the formation of MoS 2. [ABSTRACT FROM AUTHOR]

[Display omitted] • CH 3 NH 3 Pb(I 1-x Br x) 3 perovskite thin films are successfully applied as copper-free back contact layers for CdTe solar cells. • The facile deposition process of back contact layers. • The uniformity of CdTe solar cell is improved after applying CH 3 NH 3 Pb(I 1-x Br x) 3 back contact layers. • CdTe solar cell with a CH 3 NH 3 Pb(I 1-x Br x) 3 back contact layer exhibits good stability. In this study, bromide-iodide lead perovskite (CH 3 NH 3 Pb(I 1−x Br x) 3) thin films were fabricated and applied as copper-free back contact layers for CdTe solar cells. The results reveal that the open-circuit voltage (V oc) and fill factor (FF) of the CdTe solar cells are greatly enhanced by the utilization of perovskite back contact layers. This is mainly due to the evidently reduced charge transportation barrier at the back contact, which is verified by temperature-dependent current–voltage (J-V-T) and apparent quantum efficiency (AQE) measurements. Specifically, after the application of perovskite back contact layer, the best-performing device shows 15.80% improvement in efficiency (from 10.82 to 12.53%), with V oc and FF increasing by 3.94% and 6.91%, respectively. Besides, the overall uniformity of the solar cells is also improved by the perovskite back contact, suggested by laser beam induced current (LBIC) results. Further simulation results confirm the experimental results and clarify the optimized cell performance by perovskite back contact layer in terms of both energy band alignment and charge carriers' recombination. In addition, in the simulation section, we have also investigated the effect of the bandgap, thickness and doping level of perovskite and the doping level of CdTe on the cell performances. The experiments and the numerical simulation reported in this work suggest perovskite a potential copper-free back contact layer for the fabrication of efficient CdTe solar cells. [ABSTRACT FROM AUTHOR]

Sb 2 S 3 has a unique one-dimensional structure-composed (Sb 4 S 6) n ribbons leads to strong anisotropic carrier transport characteristic: carrier transport along the (Sb 4 S 6) n ribbon is more efficient than other ribbons. Therefore, it's crucial to control the direction of grain growth along the (hk1) orientation. In this work, the close space sublimation method was utilized to fabricate Sb 2 S 3 thin films with a systematic al regulation of substrate temperature. The results demonstrate that optimized Sb 2 S 3 thin film presented preferred orientation at the direction of (hk1). The champion device based on Au and Ni electrodes achieved a power conversion efficiency (PCE) of 3.06% and 1.69%, respectively. Schematic diagram of the close space sublimation system. [Display omitted] • The (hk1)-oriented Sb 2 S 3 thin films were prepared by close space sublimation method. • Study of the effect of different substrate temperatures on the structure and morphology of Sb 2 S 3 thin films. • Solar cells with structure of FTO/TiO 2 /CdS/Sb 2 S 3 /Ni were fabricated. • Ni was firstly used as the electrode for Sb 2 S 3 solar cells. [ABSTRACT FROM AUTHOR]

The band gap of CdS (E g = 2.4 eV) was narrow, which made it unable to transmit short-wave sunlight through the CIGS absorber layer. Zn(O,S) thin film, prepared by doping O into ZnS, had a wider band gap, and the raw material was green and non-toxic, making it suitable as a buffer layer for solar cells. However, CBD-Zn(O,S) usually takes longer than CdS deposition. In this work, By shortening the deposition time through the fast hydrolysis of TAA. Na 3 NTA was added in the solutions to improve the quality of Zn(O,S) thin films. The effect of Na 3 NTA concentration on the complex ion contents was investigated. When Na 3 NTA was added at a concentration of 0.04 M along with TAA (0.04 M), the film had a high T% of 88.6%, E g of 3.76 eV, and a dense grain distribution. ZnS and ZnO grew at (111) and (100) crystals, respectively. Raman and XPS analyses showed the existence of Zn–S and Zn–O bonds, indicating the high crystalline quality of the Zn(O,S) thin films prepared with CBD. Finally, when the optimal concentrations of ZnSO 4 , NH 4 OH, Na 3 NTA, and TAA were 0.04 M, 0.48 M, 0.04 M, and 0.04 M, respectively, the prepared Zn(O,S) thin films could be used as a cadmium-free buffer layer for solar cells. • NH 4 OH and Na 3 NTA were mixed to improve the quality of grain growth of Zn(O,S). and optimized. • The microscopic morphology and the optical properties of Zn(O,S) were optimized. • The effect of pH on complex ion generation during complexation was simulated by Medusa software. • The concentrations of Na 3 NTA, and TAA were optimized, Zn(O, S) thin films, used as cadmium-free buffer layer for solar cells, were prepared. [ABSTRACT FROM AUTHOR]

As a new-type absorber material, antimony sulfide (Sb 2 S 3) possesses the advantages of earth-abundant elemental contents, low-toxic constituents, appropriate photoelectric properties, and unique one-dimensional crystal structure. We utilized the close space sublimation technique to deposit high-quality Sb 2 S 3 thin-film with (hk 1)-preferred orientation by controlling source temperature. Then, Sb 2 S 3 thin film solar cells with the superstrate structure of FTO/CdS/Sb 2 S 3 /Au were fabricated, achieving a conversion efficiency of 2.86%. To further enhance efficiency, co-selenization process was employed in the Sb 2 S 3 thin films by co-sublimation, which improve the crystallinity of films, increase grain size and form stronger (hk 1)-preferred orientation. In addition, co-selenization process can adjust band gap value and enhance junction quality. By these approaches, we enhanced the short circuit current density (Jsc) of Sb 2 S 3 solar cell efficiently. The Sb 2 S 3 solar cell fabricated by CSS achieved an efficiency of 4.45% using co-selenization process. These methods can be applied to other chalcogenides thin-film solar cells, providing a practical way for the device performance improvement. • Close space sublimation was employed to prepar Sb 2 S 3 thin film. • Sb 2 S 3 underwent the co-selenization process was synthesized by co-sublimation for the first time. • Sb 2 S 3 thin film solar cell obtained the efficiency of 2.86% by controlling the source temperature. • Se–Sb 2 S 3 soar cell fabricated by CSS achieved the efficiency of 4.45%, obtained an enhancement of 55.6%. [ABSTRACT FROM AUTHOR]

In this work, the CZTS absorbers were prepared by sol-gel method and the combination of electrodeposition and sol-gel method. The influence of Na and/or K incorporation on the thickness of MoS 2 during sulfurization process was investigated. XRD, Raman, and SEM characterizes presented that K incorporation could help to suppress the formation of MoS 2 , which induced to reduce the thickness of MoS 2. Additionally, Na and/or K doping could eliminate the existence of the voids and improve the quality of CZTS thin film. Besides, the CZTS absorbers fabricated by the combination process of electrodeposition and sol-gel shown a better adhesion than that fabricated by sol-gel method. [ABSTRACT FROM AUTHOR]