Sputtered nickel oxide (NiOx) integrated with a self-assembled monolayer (SAM) as a hole-transport layer represents a promising strategy for the scalable application of inverted (p-i-n) perovskite solar cells. However, the inherent limitations of sputtered NiOx, characterized by insufficient surface functionality, hinder the ordered deposition of SAMs, thereby constraining device performance. Here, we demonstrate a method to achieve uniform NiOx films by controlling the oxygen cooling pressure during the magnetron sputtering process. To further enhance the quality of the interface, we introduce a structural-compensation strategy comprising a sputtered underlayer complemented by a solution-processed hydroxyl-rich overlayer. The magnetron-sputtered bottom layer provides a compact, low-defect contact, while the solution-processed top layer creates a hydroxyl-rich surface, facilitating effective SAM anchoring and decoupling SAM deposition from charge extraction processes. This interfacial engineering not only enhances hole extraction, but also promotes perovskite crystallization, leading to enlarged grain sizes, reduced strain, and suppressed non-radiative recombination. Consequently, the resulting inverted devices deliver high performance across bandgaps and scales: 24.86% and 21.78% for small-area 1.55 and 1.68 eV cells, respectively, and 21.38% for a 12.4 cm2 module based on the 1.55 eV absorber, all with robust operational stability. This work provides a practical and scalable pathway toward high-performance perovskite photovoltaics.

Perovskite-silicon tandem technology has exceeded the single junction theoretical efficiency limit. However, there is still distance to the thermodynamic limit mainly caused by the fill factor. This work presents a methodology to illustrate the mechanisms of FF loss in perovskite-Si monolithic tandem solar cells. Apart from the series resistance related loss characterized by electroluminescence, another loss factor is from the photoshunt, a phenomenon in which the parallel resistance apparently reduces under illumination in perovskite solar cells due to the moderate charge transport layer mobility. In addoition, the two-diode property of the Si cell can also influence the FF of tandem devices. The photoshunt can be hidden when the bottom cell is over illuminated, which explains highly efficient tandem solar cells are usually bottom cell limited. This work outlines strategies that overcoming the photoshunt issue can move the perovskite top cell closer to low FF losses in tandem solar cells.

Aluminum-doped zinc oxide (AZO) film is a promising alternative to indium tin oxide (ITO), typical transparent conductive oxide (TCO) used in silicon heterojunction (SHJ) solar cells. However, the long-term damp heat (DH) stability of AZO-based SHJ devices remains a critical concern due to the moisture sensitivity of AZO. In this work, the mechanism of damp-heat-induced degradation (DHID) of AZO-incorporated SHJ solar cells and modules was systematically investigated and compared with ITO references. After 1000 h of DH exposure at 85 °C and 85% relative humidity, AZO-incorporated SHJ solar cells exhibited a larger efficiency loss than the ITO reference, mainly associated with a significant reduction in fill factor (FF). The FF degradation was strongly correlated with an increase in series resistance (Rs), and the increase in AZO film resistivity was identified as an important contributor to the Rs increase observed during DH exposure. X-ray photoelectron spectroscopy (XPS) revealed a pronounced increase in the OH− intensity after DH testing, suggesting moisture-induced chemical modification of the AZO surface or near-surface region. Moreover, the observed open-circuit voltage (Voc) degradation after DH exposure implies that moisture-related degradation may extend beyond the AZO surface and affect underlying passivation layers. In addition, scanning electron microscopy (SEM) revealed the formation of surface grooves on the AZO film after DH exposure. These observations, together with the electrical degradation of the AZO films and devices, are consistent with moisture-induced degradation of AZO. Furthermore, a MgF2 capping layer improved the DH stability of AZO-incorporated SHJ solar cells by mitigating moisture-induced degradation.

Abstract In recent years, the demand for catalytic devices in renewable energy applications has grown rapidly. HEMs characterized by their distinct atomic configurations, exhibit excellent chemical stability, corrosion resistance, mechanical properties, and favorable thermal stability, making them advantageous for modern catalytic technologies. This article summarizes the fundamental definition and synthetic approaches of HEMs and investigates the influencing factors of photocatalytic activity from four aspects: semiconductor band structure, charge carrier separation and migration characteristics, catalyst surface activity, and environmental parameters. Moreover, the design and preparation of HEM photocatalysts by adjusting component ratio, optimizing lattice defects, and regulating electronic structure are mainly introduced. Finally, the broad application prospects of HEMs in fields such as photocatalysis, energy conversion and storage are presented. Given the rapid development and transformative potential of HEMs in photocatalysis, a systematic review is essential to consolidate recent advances, clarify design principles, and guide future research toward efficient and stable photocatalytic systems.

Electrocatalytic water splitting is widely regarded as a sustainable and promising technology for the production of hydrogen. However, their efficiency is severely limited by the sluggish kinetics of the oxygen evolution reaction. This work demonstrates that through the rational design of single-atom catalysts (SACs), hydrazine oxidation can function as an efficient alternative anodic reaction to replace the oxygen evolution reaction, thereby substantially lowering the energy input required for hydrogen production. Using density functional theory calculations, we systematically investigated a series of single-atom 3d transition metals ranging from Sc to Zn anchored on four types of defective graphene substrates. Among the investigated systems, Cr@N4 and Fe@N4 stand out as thermodynamically promising bifunctional catalysts, exhibiting low reaction free energy barriers of 0.33 and 0.48 eV, respectively, together with high thermodynamic stability and selectivity. Meanwhile, both catalysts also demonstrate excellent hydrogen evolution reaction activity, with near-optimal hydrogen adsorption free energies of 0.09 eV for Cr@N4 and 0.11 eV for Fe@N4. Electronic structure analyses reveal a pronounced electron-acceptance-donation interaction between the single-atom active centers and N2H4 molecules, which enhances adsorption and facilitates the reaction process.

Self-assembled monolayer (SAM) hole transport layers are commonly used in state-of-the-art perovskite single-and multi-junction solar cells. Their precursor molecules are prone to aggregation. We report SAM-solution-pH-modulation that effectively suppresses aggregation, improving deposited film quality. We designed and synthesized a novel material, 6-aminohexylphosphonic acid hydrochloride (6AHPACl), to be added to the (4-(3,6-dimethyl-9H-carbazol-9-yl)butyl)phosphonic acid (Me-4PACz) solution as part of a co-SAM strategy. Apart from the advantage of pH modulation, the inclusion of 6AHPACl improved SAM anchoring, SAM/perovskite interface energetics, and wettability of the overlaying perovskite layer and therefore its quality. This co-SAM strategy enabled demonstrations of a wide-band gap (1.67 eV) perovskite cell producing a champion efficiency of 22.8% and a 1 cm2 monolithic perovskite-silicon double junction cell producing a certified efficiency of 29.1%. An encapsulated device retained 95% of its efficiency after 1,010 thermal cycles (-40 degrees C to 85 degrees C). Another encapsulated double junction device surpassed the International Electrotechnical Commission (IEC) 61215 humidity freeze test.

Wide-bandgap (WBG) perovskite solar cells (PSCs, E g similar or equal to 1.67 eV) still suffer from pronounced open-circuit-voltage (V OC) deficits. Here, we report a synergistic surface-passivation strategy that coassembles a dipolar quaternary-ammonium salt, acetylcholine chloride (ACCl), with an electron-rich long-chain alkylammonium halide, n-octylammonium iodide (OAI). A mixed ACCl:OAI treatment reconstructs the perovskite surface, lowers surface-trap density, and aligns the valence band with the hole-transport layer. Consequently, the champion WBG PSC delivers V OC = 1.29 V, J SC = 20.0 mA cm-2, FF = 82.8%, and PCE = 21.27%, corresponding to 92.8% of the Shockley-Queisser voltage limit. When integrated as the top absorber in a monolithic n-i-p perovskite/p-type Si tandem, the passivated WBG cell contributed to a PCE of 26.8% with a V OC of 1.91 V. These results reveal that cooperative defect passivation and energy-level engineering are both essential to unlock the full voltage potential of WBG perovskites.

During the development of perovskite-silicon tandem solar cells, the impact of transport layers of perovskite top cells on the short-circuit current density (J SC) has rarely been considered. Here, we report ultrathin electron-selective contacts as new architectures of electron transport layers (ETLs) by decreasing the C60 thickness to 1 nm, where the carrier collection efficiency is proven to be independent of C60 thickness with tin oxide as a buffer layer. Benefiting from the lowest C60 parasitic absorption, the J SC in the tandem device with ultrathin C60 is enhanced by 0.24 mA/cm2. Moreover, to recover the damage from atomic layer deposition on uncovered perovskite surface, we use poly(methyl methacrylate) (PMMA) as a protective layer. Combining ultrathin C60 and PMMA protective layer, an efficiency of 31.70% is finally achieved in tandem solar cells. These findings demonstrate the feasibility of ultrathin ETLs or ETL-free designs for perovskite-silicon tandem solar cells.

Zinc oxide thin films are successfully deposited using plasma‐enhanced chemical vapor deposition (PECVD), representing a novel approach for fabricating transparent conductive oxide (TCO) layers. The initial undoped ZnO film exhibits a polycrystalline structure with a pronounced (002) orientation and low optical absorptance. However, the electrical properties of the film are characterized by high resistivity and instability, primarily attributed to its porous morphology. These limitations can be addressed by incorporating aluminum‐doped zinc oxide or indium tin oxide seed layers, resulting in enhanced and more stable electrical performance. To demonstrate its applicability, this study reports the first successful integration of PECVD‐grown ZnO film as a front‐contact layer in silicon heterojunction solar cells. The addition of seed layers boosts the solar cell efficiency by increasing the fill factor through reduced series resistance. Despite the challenges with the initial film quality and the need to further refine the PECVD conditions to optimize the device performance, this study offers valuable insights into the current limitations and future potential of PECVD for TCO development. This lays the foundation for improving the PECVD process to produce high‐quality TCO, potentially establishing it as an alternative deposition method for next‐generation photovoltaic technology.

The photocatalytic performance of carbon nitride in peroxymonosulfate (PMS) activation is limited by rapid charge recombination and insufficient active sites. Herein, we report a synergistic co-doping strategy to overcome these limitations by fabricating copper and oxygen co-doped crystalline carbon nitride (Cu/O-CCN) via thermal polymerization and molten-salt treatment using copper acetylacetonate as a dual-source precursor. Comprehensive characterizations confirm atomically dispersed Cu-N4 coordination and C-O linkages from oxygen substitution at nitrogen sites. This dual doping significantly redistributes local charge density, generating a strong built-in electric field (2.69 Debye) that enhances photogenerated charge separation. Cu sites also provide efficient PMS activation sites. The optimized 0.5% Cu/O-CCN catalyst achieves rapid bisphenol A (BPA) degradation under visible light irradiation with PMS, with a first-order rate constant of 0.27 min-1, 7.5 times higher than pristine CCN. It also exhibits the highest synergy factor (3.6), outperforming O-CCN (1.9) and CuCCN (2.4). Mechanistic studies reveal multiple reactive oxygen species contribute to BPA degradation. The catalyst shows excellent recyclability (92% activity retention over ten cycles) and low Cu leaching (0.15 mg/L). Phytotoxicity assessments confirm significant detoxification, with mung bean germination increasing from 27% to 67%. This work highlights synergistic co-doping as a promising strategy to design efficient photocatalysts for PMS-based advanced oxidation processes.

Hydrogen (H) is essential for the high performance of advanced crystalline silicon (c-Si) solar cells. Recently, H-related ultraviolet-induced degradation (UVID), which can compromise module stability, has attracted increasing attention from the photovoltaic (PV) industry, yet its underlying mechanisms remain incompletely understood. Here, the severity of UVID in silicon heterojunction (SHJ) solar cells is shown to depend strongly on the illuminated-side passivating-contact design, with transparent passivating contacts (TPCs) exhibiting markedly larger losses in open-circuit voltage (V OC), short-circuit current (J SC), and fill factor (FF) than conventional hydrogenated amorphous silicon (a-Si:H)-based SHJ contacts. Combined material characterizations and device analysis support a picture in which the high transparency of TPC shifts UV energy deposition toward the c-Si near-interface region, where UV-driven Si & horbar;H bond dissociation increases interfacial recombination and degrades chemical passivation. In parallel, UV exposure induces a pronounced resistivity increase in the hydrogenated nanocrystalline silicon carbide (nc-SiC:H) contact stack, consistent with local microstructural/electronic disorder and the possible involvement of enhanced sub-bandgap absorption, thereby raising series resistance (R s) and limiting carrier collection. Collectively, these findings link contact optical transparency, H-related bond dynamics, and nc-SiC:H transport degradation to the distinct UVID signatures of SHJ architectures.

In situ interface passivation serves as a crucial strategy for improving both the efficiency and stability of wide-band gap (WBG) perovskite solar cells and their associated tandem architectures. Here, we present a one-step in situ buried-interface passivation approach designed to reduce interface defects in three-dimensional (3D) WBG perovskite films. This is achieved by constructing self-assembly of a gradient Ruddlesden-Popper (RP) two-dimensional (2D) perovskite layer at the buried interface of the 3D WBG perovskite, leading to the formation of a gradient RP-2D/3D perovskite heterostructure. Such heterostructures facilitate the oriented growth of 3D perovskite crystals along the (100) plane, enhance charge carrier extraction, and effectively passivate trap states within the WBG perovskites. The in situ formation of RP-2D/3D perovskite heterostructures significantly enhances the light, thermal, and moisture stabilities of the WBG 3D perovskites. The resulting perovskite/silicon tandem solar cells exhibit improved current matching (mismatch 0.1% vs 5.5% for 3D), deliver improved efficiency of 32.73% (certified 32.46%), and demonstrate an operational lifetime T 90 exceeding 1508 h.

Adopting half-cut solar cells reduces module losses. Further gains from architectures like Silicon heterojunction (SHJ) or passivated contacts (e.g., Tunnel Oxide Passivated Contact, TOPCon) necessitate finer sub-cells, yet their power loss mechanisms during thermal laser separation (TLS) are not fully understood. Here, we identify a hydrogen kinetics-driven divergence: SHJ suffers extensive heat-affected zone (HAZ) damage from thermally activated hydrogen diffusion and hydrogen-mediated defect creation in the a-Si:H layers, as confirmed by photoluminescence and Raman analysis, while TOPCon shows minimal edge effects. Consequently, SHJ has a critically narrower TLS window than TOPCon. This insight explains higher SHJ cutting losses and guides precision process development for future sub-cells.

Dry reforming of methane (DRM) converts greenhouse gases CH4 and CO2 into industrially valuable syngas. Using density functional theory (DFT), we evaluated the DRM catalytic performance of ten diatomic TM1-TM2 combinations (TM1, TM2 = Fe, Co, Ni, Cu) supported on double-vacancy defective graphene (DG). CoCo@DG, FeCo@DG, and CoNi@DG exhibit high catalytic activity with low barriers in CH oxidation to CO and CO2 dissociation, while carbon-removal barriers are half those for formation, ensuring stability. Pathway analysis reveals that CoCo@DG and CoNi@DG, which follow the same dominant pathway (where CH* reacts with surface O* via CHO* to form CO*), exhibit the lowest overall barriers, identifying them as the most promising nonprecious candidates. Most importantly, the activation barrier of the rate-determining step (RDS) on CoCo@DG "CH2* + * -> CH* + H*" is only 1.26 eV, thereby confirming its good catalytic activity. The activity origin is rationalized via projected density of states (PDOS), differential charge density, Hirshfeld charge distribution, and projected crystal orbital Hamiltonian population (-pCOHP) analysis. This work theoretically supports the rational design of high-performance diatomic DRM catalysts.

High-entropy materials (HEMs), especially high-entropy alloys (HEAs), have demonstrated significant potential in the field of electrocatalysis owing to their distinctive multi-component compositions and exceptional structural properties. This study presents a comprehensive overview of the fundamental principles of electrocatalysis and the conceptual framework of HEMs, highlighting their intrinsic advantages in electrocatalytic applications. These advantages encompass the multi-element synergistic effect, enhanced corrosion resistance, suppressed atomic diffusion kinetics, and the distinctive “cocktail” effect. Subsequently, the synthesis methods of HEMs are thoroughly examined, encompassing advanced techniques including but not limited to pulsed laser ablation, magnetron sputtering deposition, electrochemical deposition, and hydrothermal synthesis. The electrocatalytic applications of HEMs are systematically reviewed, and their potential implementation in industrial-scale applications and biomedical engineering is critically evaluated with particular emphasis on their performance in some key reactions, including hydrogen evolution reaction (HER), oxygen evolution reaction (OER), oxygen reduction reaction (ORR), and carbon dioxide reduction reaction (CO2RR). Industrial challenges are also critically discussed. Finally, this paper prospectively outlines future research directions and emerging trends in this field, highlighting the pivotal pathway for advancing the broad implementation of HEAs in electrochemical energy conversion systems.

Lightweight photovoltaic (PV) applications are pivotal for expanding the adoption of solar energy, enabling new installation scenarios and contributing significantly to the renewable energy capacity. However, degradation due to ultraviolet (UV) radiation is a critical concern for silicon heterojunction (SHJ) solar modules, particularly lightweight solar module configurations, where flexible polymer-based front sheets may provide reduced shielding against UV radiation. In this study, we present a comprehensive investigation of the UV-induced degradation (UVID) behavior of lightweight SHJ solar modules utilizing encapsulants with different UV-transmission: UV-blocking, UV-transmitting, and UV-downshifting. After indoor UV exposure of 120 kWh/m2, equivalent to 30 months of outdoor exposure in J & uuml;lich, Germany, solar modules incorporating these encapsulants exhibited relative efficiency losses of 2.17%, 9.25%, and 6.15%, respectively. The decrease in efficiency was mainly attributed to a reduction in the fill factor (FF) of the solar modules, accompanied by a diminished pseudo fill factor (pFF). Based on detailed FF and pFF loss analyses, we found that pFF loss was the major cause of FF loss, which is attributed to the deterioration of the passivation properties due to UV radiation. Additionally, the influence of series resistance (R s)-related FF losses increased, which is attributed to the deterioration of the interconnection foil rather than the UV radiation itself. Additionally, while downshifting (DS) encapsulants helped mitigate UV damage, we observed a diminished DS effect in lightweight configurations, potentially due to photooxidation. Utilization efficiency of DS decreases from around 34% to 21% after 120 kWh/m2 of UV exposure. Therefore, a novel encapsulation architecture combining UV-downshifting and UV-blocking encapsulants was proposed to ensure the UV utilization and stability of lightweight SHJ solar modules. Solar modules featuring this innovative dual-layer structure preserved over 98% of their initial performance after UV exposure, demonstrating a promising new approach for enhancing UV stability. The comprehensive investigation provides substantial insights into the degradation mechanism of lightweight SHJ solar modules under UV exposure and offers practical strategies in the progress of improving their durability and performance.

Self-assembled monolayers (SAMs) represent an effective strategy for the development of perovskite solar cells (PSCs). High-performance PSCs are typically fabricated in an inert atmosphere because ambient moisture disrupts phosphonic-acid SAMs on transparent conductive oxides, leading to surface inhomogeneity and direct exposure of the transparent conductive oxide. However, this dependence on glovebox fabrication constrains scalability and cost-effective manufacturing. Here we present a ternary self-assembled molecular contact comprising glycerol dimethacrylate and 1-acetylguanidine that serves as a process-tolerant hole-selective contact. Glycerol dimethacrylate acts as a cosolvent during SAM deposition to improve film uniformity and is subsequently transformed into a hydrophilic binary network upon mild thermal curing, firmly anchoring the SAM to the substrate, whereas 1-acetylguanidine is incorporated to further suppress interfacial defects. Wide-bandgap PSCs fabricated in ambient conditions achieve a power conversion efficiency of 21.20% (1.00 cm2), with an open-circuit voltage of 1.28 V. When implemented in monolithic perovskite/silicon tandems, cells achieve a power conversion efficiency of 31.72% (certified 31.36%) and 32.60% for fabrication in ambient and inert conditions, respectively. These findings demonstrate that our tailored hole-selective contact provides a robust and process-tolerant interfacial engineering approach for high-efficiency perovskite and tandem photovoltaics manufactured under ambient conditions.

This work investigates the influence of the metallization of low-temperature Cu paste and AgCu paste on the performance of SHJ solar cells through a comprehensive study of two techniques-screen printing (SP) and dispensing. The research successfully applied Cu and AgCu pastes as metal contacts on SHJ solar cells, yielding promising results. Notably, cells with AgCu paste SP on the front side and Ag paste SP on the rear side achieved a 0.13% efficiency gain over reference Ag SP bifacial cells. Moreover, cells with AgCu paste SP on the front side and Cu paste SP on the rear side reached an efficiency of 23.6%, just 0.35% lower than the reference cells, while saving approximately 70% of Ag paste. Cells with Cu paste SP on both sides recorded an average efficiency of 22.4% and a maximum of 23.08%, the highest efficiency reported for cells using Cu SP on both sides (zero Ag). Cells with Cu dispensing on the rear side also demonstrated superior performance compared to cells with Cu SP on the rear side. Along, we assessed the finger-printed characteristics of the three pastes and the performance of SHJ solar cells under various annealing conditions including the Cu annealing conditions (300 degrees C for 5 s). The solar cells maintained stable performance up to 280 degrees C for 5 s, with degradation observed above this temperature, and light soaking partially recovered some of the efficiency loss. A 0.2% drop persisted under Cu annealing conditions, but light soaking reversed this effect back to the original efficiency. This work advances SHJ solar cell technology by highlighting the potential of AgCu and Cu pastes to efficiently replace or reduce Ag paste consumption in SHJ solar cell metallization.

Polymeric carbon nitride (PCN, also called melon) was a potential photocatalyst for the CO2 reduction reaction (CO2RR), but the conjugation of the system inhibited the efficiency. By modifying melon with non-metal elements such as boron (B), phosphorus (P), oxygen (O), and sulfur (S), we found that S (or O) doped melon (S/melon, O/melon) transformed the reactive site of pyridine nitrogen (N) to carbon (C), which promoted COOH* hydrogenation to CO* and, thus, improved the CO2 reactivity and CO selectivity significantly. In addition, nonadiabatic molecular dynamics simulations showed that the trap states of the O/melon and S/melon can rapidly capture excited electrons to participate in the CO2RR and improve the photocatalytic reaction efficiency. This work provided theoretical insight for the design of efficient CO2RR photocatalysts based on metal-free materials.