To overcome the bottlenecks of pure ZnO—narrow photoresponse, rapid carrier recombination, and severe photocorrosion—we prepared three Type-II heterojunction photocatalysts (ZnO/TiO₂, ZnO/WO₃, ZnO/CeO₂) via a sol-gel method. We focused on how differences in the band edge positions of the secondary semiconductors regulate reactive species and dye degradation selectivity. Although all three follow Type-II charge transfer, the distinct CB/VB energy levels of TiO₂, WO₃, and CeO₂ determine the enrichment sites and redox capabilities of photogenerated carriers, leading to a shift in dominant reactive species: ZnO/CeO₂ generates both •OH and •O₂⁻, ZnO/TiO₂ mainly •O₂⁻, and ZnO/WO₃ mainly •OH. Consequently, they exhibit differential degradation toward methyl orange (MO, anionic) and methylene blue (MB, cationic). Benefiting from the Ce⁴⁺/Ce³⁺ redox cycle and high oxygen vacancy concentration, ZnO/CeO₂ shows the best carrier separation and reactive species yield, achieving degradation rates 2.30 (MO) and 3.14 (MB) times higher than pure ZnO. This work establishes an intrinsic structure–activity relationship among band edge positions, reactive species type, and degradation selectivity, providing theoretical and experimental support for the targeted design of ZnO-based photocatalysts for water remediation.

The incorporation of the Se element in CdTe solar cells is critical, while the low bandgap CdSexTe1-x, formed by the interdiffusion of CdTe and CdSe during device preparation, can promote the carrier lifetime. Different window layers formed by CdSe w/o MZO or CdS have different Se distributions. This paper systematically evaluates the influence of four types of window layers (CdSe, CdS/CdSe, MZO/CdSe and MZO/CdS/CdSe) on the performance of CdTe solar cells, and focuses on the correlation between the window layers and the Se distribution characteristic, carrier recombination mechanism, and device efficiency. The results show that CdSe and MZO/CdS/CdSe window layer devices achieve Eff of 15.21% and 14.40%, respectively. The CdSe and MZO/CdS/CdSe devices exhibit relatively high Ea of 1.41 eV and 1.39 eV from J-V-T measurements, coupled with high Rrec of 9458 Q and 8293 Q, respectively. This indicates suppressed recombination, suggesting that non-radiative recombination is reduced. In contrast, the CdS/CdSe and MZO/CdSe devices show lower performance. Their extrapolated Ea values are 1.25 eV and 1.31 eV, with correspondingly lower Rrec values of 2207 Q and 3304 Q. These results point to faster recombination rates and an increased proportion of non-radiative recombination, consistent with their suboptimal Eff. Detailed analysis of Se distribution reveals that S-Se interdiffusion in S-containing devices results in the x-value decrease (highest value of Se content in CdSexTe1-x), thereby suppressing the long-wavelength expansion. In devices of S-free window layers, the formed CdSexTe1-x alloy has a relatively higher x-value, allowing the long-wavelength response to extend beyond 850 nm. It can be concluded that CdSe is the optimal window layer for CdTe Solar Cells, which can both form a desirable Se distribution and a good junction with less interface recombination.

A crown ether named dibenzo-18-crown-6 is introduced to modify the interface between the perovskite and the electron transport layers. Due to its unique electron cavity and electron-rich system, it effectively passivates defects and simultaneously suppresses cation migration, thereby achieving a high power conversion efficiency of 24.19% with excellent stability.

Tunnel Oxide-Passivated Back Contact solar cells represent a next-generation photovoltaic technology with significant potential for achieving both high efficiency and low cost. This study addresses the challenge of low bifaciality inherent to the rear-side structure of TBC cells. Using the Quokka3 simulation and assuming high-quality surface passivation and fine-line printing accuracy, a systematic optimization was conducted. The optimization encompassed surface morphology, optical coatings, bulk material parameters (carrier lifetime and resistivity), and rear-side geometry (emitter fraction, metallization pattern and gap width). Through a multi-parameter co-optimization process aimed at enhancing conversion efficiency, a simulated conversion efficiency of 27.26% and a bifaciality ratio of 92.96% were achieved. The simulation analysis quantified the trade-off relationships between FF, bifaciality, and efficiency under different parameter combinations. This enables accurate prediction of final performance outcomes when prioritizing different metrics, thereby providing scientific decision-making support for addressing the core design challenges in the industrialization of TBC cells.

The glass frit composition in silver paste is critical to the Ag-Si contact resistance of crystalline silicon solar cells and thus the device's power conversion efficiency (PCE). Glass frits employ silicon dioxide as the primary network former to construct an amorphous network, with additives such as PbO, Bi2O3, and TeO2 used to regulate their structural stability, high-temperature wettability, and interfacial reactivity. However, existing studies have predominantly focused on the regulation of glass frit properties by components like Bi2O3 and TeO2, while the systematic impact mechanism of the PbO/SiO2 molar ratio-a core parameter-remains insufficiently elucidated. In this work, a series of glass frits with varying PbO/SiO2 molar ratios were synthesized. The effects of the ratio on the glass transition temperature (Tg) and amorphous structure were characterized, and the frits were formulated into silver paste for application in monocrystalline silicon solar cells to evaluate their regulatory effects on Ag-Si contact resistance and cell performance. The experimental results show that as the PbO/SiO2 molar ratio decreases from 10 to 2, the interfacial specific contact resistance initially decreases and then increases. At an optimal PbO/SiO2 molar ratio of 6, the glass frit achieves an optimal balance between the glass transition temperature (288 degrees C) and high-temperature reactivity, forming a continuous amorphous layer and uniformly distributed silver nanoparticles at the interface. This reduces the specific contact resistance to as low as 0.79 m Omega cm(2), which is an similar to 8% reduction compared to groups with extreme PbO/SiO2 molar ratios, and increases the corresponding cell PCE to 23.65% (an improvement of similar to 1 percentage point).

The bis-phosphonic acid groups of 1,4-phenylenebis(phosphonic acid) passivate defects at the buried interface, enabling 1.66 eV WBG PSCs with a high V oc of 1.195 V, 21.79% efficiency, and enhanced stability.

Although metallic aluminum (Al) is an attractive back electrode material for cadmium telluride (CdTe) solar cells due to its low cost and suitability for large-area deposition, its low work function has hindered widespread application. To overcome this challenge, we designed and implemented a molybdenum-chromium (Mo/Cr) interfacial modification layer. A comprehensive comparative analysis was carried out to evaluate the electrical characteristics, interfacial transport properties, and device performance of the Al, Mo/Cr-modified Al and Au electrodes. The results reveal that the Mo/Cr interfacial modification layer effectively improves Al-electrode interfacial transport properties and conductivity and also blocks the diffusion of Al atoms. The optimized device with a Mo/Cr-modified Al electrode achieved a champion efficiency of 15.68%, closely approaching 15.88% of the expensive, high-work-function gold (Au) reference and significantly surpassing 13.83% of the Al electrode. Furthermore, it exhibited excellent mechanical adhesion and wear resistance, with a critical load of 0.62 mN, substantially higher than the 0.45 and 0.42 mN for the Al and Au electrodes, respectively. This electrode architecture offers a low-cost, highly durable, and high-performance alternative to noble-metal contacts, showing great potential for facilitating the large-scale commercialization of thin-film photovoltaic technology.

Introducing a 2D perovskite layer on the surface of 3D perovskite has been broadly recognized as an effective strategy to enhance the performance of perovskite solar cells (PSCs). However, the mechanism governing the 2D phase formation remains uncertain. In this work, the phase transitions of 2D perovskite during spin-coating and annealing processes has been investigated. Our findings reveal a dimensional phase shift from low to high n-value 2D phases, driven by the release of organic cations during annealing. Additionally, the spin-coating process exhibited concentration-dependent behavior, where higher n-octylamine hydrobromide (OABr) concentrations predominantly formed n = 1 phases. These observations highlight the complexity of the 2D phase composition at the 2D/3D interface. The coexistence of various 2D phases significantly influences device performance, as a conflict between n = 1 and n ≥ 2 phases was identified. Through forming a well-balanced proportion of different 2D phases, we achieved a wide-bandgap perovskite solar cell with a significantly improved power conversion efficiency of 19.29%. This work suggests the critical roles of phase dynamics and n-value distribution in optimizing 2D/3D interfaces for advancing high-performance wide-bandgap PSCs.

Doping the absorber layer is a critical process for enhancing the performance of polycrystalline CdSeTe solar cells. Replacing traditional Cu doping with Group V dopants offers a pathway to fabricate devices with improved efficiency and stability. However, the dopant activation rate in polycrystalline structures remains low, typically only a few percent. While rapid thermal annealing (RTA) has been successfully employed to achieve high activation rates in single-crystal CdTe devices, its application to polycrystalline CdSeTe solar cells has been scarcely reported. In this study, we systematically applied multi-step annealing to investigate the dopant activation of in-situ As-doped polycrystalline CdSeTe devices. Our findings reveal that polycrystalline devices exhibit significantly lower thermal tolerance than their single-crystal counterparts, sustaining only short-duration annealing at 500 degrees C. Furthermore, although Cl diffusion during RTA can degrade device performance, we observed that trace amounts of CdCl2 vapor can help stabilize device efficiency.

Enhancing the efficiency and stability of perovskite solar cells is critical for commercialization. As short-circuit density approaches the Shockley-Queisser limit, improving open-circuit voltage and fill factor becomes essential, achievable through interface engineering. SnO2, employed as a buried electron transport layer, not only influences the deposition of perovskite film but also poses significant stability. Here, we introduce a multifunctional amphiphilic molecule, hydroxyl-terminated perfluoroalkyl sulfonamide, into the buried interface. The C-F long chain facilitates hydroxyl groups anchoring on the SnO2 surface, while the sulfonyl groups occupy oxygen vacancies, thereby reducing undercoordinated Sn4+. Simultaneously, the sulfonyl groups interact with uncoordinated Pb2+ in the adjacent perovskite film, further suppressing interfacial defects. This strategy yields a champion power conversion efficiency of 23.26%. Moreover, the long C-F chains act as a hydrophobic barrier against moisture ingress, enabling the unencapsulated devices to retain 73.8% of initial PCE after 1320 h under ambient condition (50%-60% relative humidity), while only 69.4% for reference one. Furthermore, posttreatment with quaternary ammonium iodide creates a dual-passivated interface. This suppresses halide ion migration and photoinduced phase segregation, boosting the PCE to 24.64%. These results underscore the critical role of multifunctional organic molecular passivation at interface in achieving both high-performance and durable perovskite photovoltaics.

Back surface engineering is one of the ways to further improve the conversion efficiency of the CdTe solar cells. In this work, as an oxide mixture, Cu x In y O is synthesized by low-temperature solution processing and successfully applied to the CdTe solar cells in the form of amorphous nanoparticles. The XPS results reveal changes in the chemical states of Te and O, and the KPFM demonstrate that a similar to 350 mV electric field has been introduced at the CdTe back surface, which means effective chemical passivation and field passivation were induced, resulting in the suppression of carrier recombination and the increase of carrier lifetime at the back interface of the devices. Finally, compared to the control devices, the conversion efficiency of the devices with Cu x In y O buffer layer improved from 12.44% to 15.35%, attributed to the increase in the fill factor from 65.52% to 72.48% and the open-circuit voltage from 723 mV to 798 mV.

Abstract Against the global demand for renewable and sustainable clean energy, perovskite solar cells (PSCs) have shown great potential as a next-generation photovoltaic technology, owing to their high photoelectric conversion efficiency (PCE) and low-cost potential. Although the highest PCE of PSCs has exceeded 27%, poor stability and severe nonradiative recombination loss still hinder their further development. PSCs contain several critical interfaces, including the electron transport layer (ETL)/perovskite, hole transport layer (HTL)/perovskite, and charge transport layer (CTL)/electrode, which strongly influence carrier dynamics and dominate device efficiency and stability. Interface engineering has attracted extensive attention as an effective modification strategy, yet a systematic review focusing on its working mechanism is insufficient. In this review, we analyze the influence of interfacial defects on carrier dynamic processes and comprehensively summarize the latest progress of interface engineering in PSCs from ETL/perovskite, HTL/perovskite, and CTL/electrode aspects. We highlight the key roles of interface engineering in rationalizing energy-level alignment, passivating defects, optimizing perovskite film quality, and improving device stability. We also provide general guidance for selecting appropriate interfacial strategies according to specific performance bottlenecks. Finally, the challenges and future perspectives of interface engineering toward high-performance PSCs are discussed.

Due to the excellent optical and electrical properties, CuCl is emerging as a promising material for enhancing the efficiency of CdTe solar cells. In this work, we present a low-cost, solution-based method for CuCl doping, which not only significantly reduces Cu dosage but also enhances the efficiency of Cu incorporation compared to traditional deposition techniques that are often costly and time-consuming. When CuCl was applied to a device structured as FTO/MZO/CdS/CdSe/CdTe, the experiments revealed that optimal efficiency was achieved with a CuCl volume of 300 mu L and an annealing temperature of 280 degrees C. This configuration resulted in an impressive efficiency of 17.3% (cell area = 0.24 cm(2)) without the use of an antireflection coating, representing nearly a 40% increase over the control cell's efficiency of 12.38% . The observed improvements can be attributed to an increase in carrier concentration and a reduction in the back contact barrier, which collectively lead to a remarkable short-circuit current density of 30.3 mA/cm(2), nearing the highest level reported for Cu-doped devices in the literature.

Introducing a back-contact material is a crucial strategy for enhancing the efficiency of cadmium telluride (CdTe) solar cells. This work pioneers the application of a solution-processed copper(I) bromide (CuBr) layer as an efficient back-contact for CdTe solar cells. The CuBr layer serves a dual purpose: it effectively reduces the backcontact barrier, as evidenced by the elimination of the upward bending in Mott-Schottky curves and the "rollover" phenomenon in dark current density-voltage characteristics, and it acts as a source for copper doping into the CdTe absorber. This doping increases the hole concentration, leading to a significant enhancement in the apparent carrier density and a reduced saturation dark current density. Consequently, key device parameters were substantially improved, including an increase in open-circuit voltage (from 788 mV to 824 mV) and a reduction in series resistance (from 4.45 Omega & sdot;cm2 to 2.90 Omega & sdot;cm2). Ultimately, an optimized device with an FTO/ MZO/CdSe/CdTe/CuBr/Au structure achieved a power conversion efficiency of 14.7 %.

Cadmium Telluride thin film solar cell is very suitable for building integrated photovoltaics due to its high efficiency and excellent stability. To further reduce the production costs, relieve the scarcity of Tellurium, and apply in building integrated photovoltaics, ultra-thin CdTe photovoltaic technology has been developed. Some study have discussed the research progress of ultra-thin solar cells in terms of silicon and copper indium gallium selenide solar cells, but there are few review papers from the aspect of CdTe solar cells. This review focuses on the ultra-thin CdTe solar cell for the first time and provides a comprehensive and systematic summary. Firstly, the structure of this device is described, and the history of its development is reviewed. Secondly, the advantages and disadvantages of different methods are discussed, and the corresponding solutions are given. Thirdly, the factors limiting device efficiency are analyzed and future directions are suggested. Lastly, the application of ultra-thin device in semi-transparent devices is presented and the challenges are summarized. By reviewing a wide range of materials, we aim to provide valuable insights into the development of ultra-thin cadmium telluride solar cells and to promote its application in building integrated photovoltaics, which is of great importance in reducing carbon emissions to achieve sustainable development.

In recent years, the development of building integrated photovoltaics (BIPV) has brought new research hotspots and challenges to ultra-thin cadmium telluride (CdTe) solar cells. In this work, we report the first application of solution-synthesized and air-stable CuxByO film for high-performance ultra-thin CdTe solar cells and characterize the properties of materials and devices by SEM, KPFM, TOF-SIMS, J-V, C-V, EQE, etc. The results show that the CuxByO layer exhibited a 5.4 eV work function and the carrier concentration of ultra-thin devices exceeded 1015 cm- 3. Finally, the devices with a 0.8 mu m CdTe absorber layer achieve a conversion efficiency of 12.79 % with the open-circuit voltage of 810 mV, and a fill factor of 75.5 %, which was the best conversion efficiency for ultra-thin CdTe solar cells with no more than 1 mu m absorber layer. Furthermore, we use transparent electrodes instead of Au electrodes to achieve bifacialization, and the bifacial devices with the same thickness of absorber layer obtain an efficiency of 10.27 % under front illumination, and an efficiency of 4.28 % under back illumination. Our approach has demonstrated the CuxByO buffer layer by a low-temperature solution processing holds great potential for the advancement of high-performance ultra-thin mono- and bifacial CdTe solar cells.

Obtaining high‐quality perovskite films is crucial for reducing non‐radiative recombination and improving device performance. As reported, the crystallization process of perovskite films can be effectively tailored by introducing multifunctional additives. In this work, polyvinyl pyrrolidone (PVP) with varying degrees of polymerization (DP) values (K15, K30, and K90) are systematically screened and utilized as an additive to regulate defect density and control the crystallization process of perovskite films. This regulation is achieved through coordination interactions between perovskites and their multi‐carbonyl groups of PVP. Among the selected polymers, the K30 carbonyl polymer exhibits a suitable viscosity and bind strength, which facilitated a significant delay in the intermediate phase transition and accelerated nucleation. As a result, high‐quality perovskite films with enhanced crystallinity, prolonged PL lifetime, and no residual PbI 2 are achieved. The K30‐treated MA‐free device demonstrated a PCE of 24.16% with a remarkable V OC of 1.2 V. Moreover, this strategy can be extended to RbCsFAMA quadruple‐cation perovskite films, delivering an impressive PCE of 25.35% with a minimal V OC deficit of 0.35 V. This work provides an effective approach to modulate the crystal growth of perovskite films and highlights the significance of the DP values for polymeric additives.

In this paper, cadmium telluride (CdTe) has been employed as the converter material to transduce beta particles emitted by tritium (H-3), with the aim of developing betavoltaic cells. The device structure was designed and the optimal thickness of CdTe film was determined using Monte Carlo simulation. The annealing process was carefully optimized with appropriate temperature and duration selected to reduce the dark current of the device to 1.31 x 10(-12) A. Additionally, to improve the V-OC of the device, a passivation layer of aluminum oxide (Al2O3) has been employed at the back surface of CdTe. The devices with the Al2O3 layer exhibit a median V-OC of 196.5 mV, while those without Al2O3 only show a median V-OC of 164 mV. The maximum V-OC of the device reaches 224 mV. Detailed discussion confirms that the Al2O3 passivation layer can reduce the dark current and enhance the device performance. The origin of the relatively low I-SC value is also analyzed.

Durable shelf-life of precursor solutions is crucial for obtaining high-quality and stable perovskite films, which significantly affect the efficiency and stability of perovskite solar cells (PSCs). However, iodides in perovskites are easily oxidized by oxygen, especially under light exposure, reducing the shelf-life of precursor solutions and compromising perovskite films. Herein, we introduce sodium thiosulfate (ST) into perovskite inks to in situ tailor the crystallization of perovskites and suppress oxidation of iodides. As expected, this ST strategy effectively suppresses the iodide oxidation, and inhibits phase transitions and separation, thereby obtaining high-quality perovskite films with enhanced high crystallinity and reduced non-radiative recombination. Interestingly, the shelf-life of precursor solutions was extended over 60 days, and no phase transition can be found in perovskite films during 60 days of 1 sun light exposure. As a result, the champion ST-treated device achieves a PCE of 25.25% with a minimal voltage deficit of 0.35 V. More importantly, the unencapsulated devices demonstrate excellent long-term storage, thermal and light-soaking stability, delivering 93%, 85% and 85% of their original efficiencies after aging, respectively. This work provides an effective approach to extend the shelf-life of precursor solutions and improve the efficiency and operational stability of PSCs.

Low-dimensional lead-free perovskite single crystals (SCs) have exhibited great potential in high-energy ionizing radiation detections owing to their outstanding sensitivity and charge transport properties. However, the preparation of chlorine-based SCs is more challenging due to their low solubility in organic solvents and acidic solutions. In this work, we report a universal growth strategy of hydrochloric acid-assisted temperature lowering for low-dimensional layered perovskite CsMnCl3·2H2O SCs. Compared with SCs prepared by solution evaporation crystallization, centimeter-sized SCs were achieved with ultrahigh crystal quality, showing a very small full width at half-maximum of 0.02° at the plane (002). Our layered perovskite CsMnCl3 2H2O X-ray detector shows unique anisotropic X-ray detecting performance at parallel and perpendicular to the (002) crystal plane. An ultralow detection limit of 9.3 nGyair s-1 has been obtained, which is significantly lower than the 5.5 μGyair s-1 required for regular medical diagnostics. Furthermore, the device shows enhanced stability with a slight degradation of 8% after storage in air ambient for 6 months. Our work suggests a promising approach to fabricate high-quality SCs for sensitive and stable X-ray detection applications.