Identification of degradation pathways is crucial for enhancing stability of organic solar cells (OSCs) but is challenging due to complexity of functional layers and their interfaces. This study employs planar heterojunction (PHJ) and bulk heterojunction (BHJ) devices with fine-turned active layer microstructures combined with various representative hole transport layers (HTLs) to identify device degradation pathways and mitigation strategies. Based on PHJ devices, we reveal interfacial changes between HTLs and polymer donors under illumination as the dominant degradation pathway. Crucially, polymer donors with more face-on orientation, higher crystallinity and larger aggregation size can effectively mitigate interface-related degradation. Accordingly, BHJ devices based on four material systems showed that active layers with higher crystallinity and larger domain size result in significantly enhanced device photostability across all the investigated HTLs. These findings provide guidelines for morphology engineering towards photostability enhancement of OSCs.

Using sunlight and water to get hydrogen (H2) offers a promising pathway toward a sustainable future. Severe recombination of photogenerated electron-hole pairs directly impedes photocatalytic H2 production, while the strong polarized field from ferroelectric materials has been demonstrated to effectively promote charge separation. However, several drawbacks still remain, such as low piezoelectric coefficient, difficulty in forming a polarized field, and complex calcination preparation process. Herein, we present an in situ heterogeneous nucleation crystallization strategy for organic-inorganic hybrid perovskite ferroelectrics, involving heterogeneous crystallization on the surface of solid photocatalyst, the emanation of a polarized field, and the enhancement of photocatalytic H2 production. Under the mechanical stimulus, a polarized field is generated with deformation of the molecular ferroelectrics, which reinforces the charge separation efficiency. Thus, photocatalytic H2 production increases to 6.725 mmol g-1 h-1, almost 26-fold compared to the control C3N4 catalyst (0.255 mmol g-1 h-1). Our work demonstrates the extensive application of molecular ferroelectrics for high performance photocatalyst design with enhanced photocharge separation.

Homogenizing the upper surface through posttreatment has made great progress in perovskite solar cells. In contrast to the exposed surface, there are no practical remedies if imperfections form randomly at the hidden buried interface after perovskite film generation. Here, we reveal a severe distribution of residual lead iodide, voids, and grain-surface concavities at the buried interface, which severely trap carriers in inactive regions. To address these challenges, we introduce a potassium dihydrogen phosphate competitive-binding interlayer that systematically reduces residual solvents at the buried interface through strong chemical interactions. Homogenized buried interface along with facilitated perovskite film quality and charge extraction have been achieved, enabling year-round improvements in photovoltaic performance and reproducibility. The resultant devices achieve a champion power conversion efficiency (PCE) of 26.3% (certified at 25.8%) for a 0.07-square centimeter device and 25.17% for a 1.028-square centimeter device. The device also demonstrates exceptional stability, maintaining 97% of its initial PCE after 1000 hours of continuous maximum power point tracking.

Single crystal high-resolution array patterning of halide perovskite films is a crucial step toward unlocking their full potential for various optoelectronic applications. The top-down manufacturing strategies are hindered by the intrinsic fragility and thermal instability of halide perovskites. Herein, we establish an integrated growth-patterning strategy using a polymer with polar functional groups, leveraging the polymer's steric hindrance effect during crystal growth, thus reducing nucleation density and suppressing crystal growth rate, and simultaneously, improving its mechanical strength and thermal stability by a coordinative polymer protective layer with the film surface. Moreover, the polar functional groups effectively suppress surface defects and enhance the crystalline quality through coordinative interaction. This integrated method can also be used to realize centimeter-sized (∼200 mm2) and high aspect ratio (104) single crystal films growth and patterning in a variety of halide perovskites. The integrated growth-patterning strategy facilitates the commercialization of halide perovskites.

Harvesting energy from low‐frequency disordered raindrop motion has emerged as a promising hydrovoltaic technology for power generation in recent years. Hydrovoltaic devices have garnered widespread attention due to their miniaturization, portability, and substantial power generation potential. However, solid‐liquid interactions in conventional hydrovoltaic devices are limited by the strong screening charge effect of the film structures, which leads to diminished device performance. This work presents a three‐dimensional (3D) synergistic strategy for patterning zinc oxide (ZnO) hydrovoltaic devices to achieve high voltage output. At 50% relative humidity and 20 °C, the single patterned ZnO hydrovoltaic device can continuously generate a pulse voltage exceeding 9 V within 7 h, which is 15 times greater than the 0.6 V of similarly sized ZnO thin‐film device. Further assembling multiple parallel units of patterned ZnO, a power supply is conducted well for a watch demonstration. Moreover, the lightweight (20 g m −2 ) and flexible characteristics of the patterned ZnO hydrovoltaic devices make them ideal for large‐area integration and energy collection in practical applications. Thousands of printed and fabricated patterned ZnO devices will be expected to establish surface micro/nanostructure platforms for various energy devices in outdoor environments through extensive series‐parallel connections.

Large-size grains play a crucial role in enhancing the properties of ferroelectric films and improving device performance. In this work, hydroiodic acid is used as an additive to promote the crystallization of a narrow-band gap molecular ferroelectric film (hexane-1,6-diammonium pentadiammonium). The complex-regulated processes resulted in a significant increase in grain size from 0.2 to 6.4 mu m (32-fold enhancement), accompanied by a reduction in band gap, optimization of the energy level structure, and enhancement of ferroelectric properties. The optimized film exhibited nearly a 10-fold improvement in the performance of ferroelectric photovoltaic devices, which is further enhanced after polarization. This study introduces complex regulation strategies for optimizing molecular ferroelectrics, offering valuable insights for future research on molecular ferroelectrics.

Production of hydrogen fuel from water and renewable energy offers one of the most promising pathways for carbon neutrality and sustainable development. However, existing hydrogen generation technologies struggle with durability issues, such as poisoning, coking, and fouling, so it is a crucial economic concern to find a long-term hydrogen generation catalyst or approach. Herein, we report a recyclable cyclic supersaturation strategy harnessing molecular ferroelectric (TMFM)0.26(TMCM)0.74CdCl3 (MF-1) for hydrogen generation, which enables cycles of recrystallization and dissolution of molecular ferroelectric nanocrystals in supersaturated aqueous solution systems. The molecular ferroelectric nanocrystals generate hydrogen through the piezoelectric effect and dissolve in aqueous solution, enabling complete hydrogen desorption. Additionally, their low acoustic impedance, closely matching that of water, facilitates efficient mechanical energy transmission, thereby enhancing hydrogen generation efficiency. We achieve a robust hydrogen generation rate of record-high 11.56 mmol g-1 h-1 (mechanical-to-hydrogen energy conversion efficiency of 35.6%), with outstanding durability surpassing 1500 h. This work not only provides a new strategy for efficient and sustainable hydrogen generation but also boosts the outlook for the application of water-soluble molecular ferroelectric materials.

Reaction interphase modulation plays a key role in the performance of lithium metal anodes. Herein, novel hybrid plasma technologies are developed to regulate three main interfaces including the bottom nucleation interface between the backbone and lithium, the middle interface between solid electrolyte interphase (SEI) and lithium, and the upper interface between SEI and electrolyte to achieve uniform deposition of Li+ and suppress the growth of dendrite. Specifically, plasma-derived vertical graphene is grown on sponge nickel fiber to optimize the bottom nucleation interface, which can spontaneously form a gradient distribution of current density to induce a uniform bottom-to-up deposition of Li. On this base, a unique tri-gradient inorganic-organic SEI (Li3N/Li2O & horbar;RCOOLi) is constructed on Li metal via N2 and ethylene carbonate hybrid plasma. The plasma-SEI is dominated by inorganic components, where the outer layer is Li3N/Li2O-rich interphase with a low desolvation energy for electrolyte and the inner layer is mainly composed of Li2O with a high interfacial energy to promote a lateral diffusion of Li. The designed interphases synergistically enhance the structure and interface stability, reduce side reactions with electrolyte, facilitate uniform deposition of lithium, and suppress the Li dendrite, leading to an enhanced cycling life of 2275 h and high coulombic efficiency.

Two-dimensional (2D) halide perovskites have garnered significant interest owing to their facile solution processing, high quantum yield, and tunable photoelectronic properties. The formation of lateral heterostructures by 2D halide perovskites offers exceptional electronic and photoelectronic characteristics. However, the stability of 2D halide perovskite lateral heterostructures is compromised by the substantial intrinsic ion migration within the perovskite structure. Consequently, the suppression of ion diffusion at the interface is crucial to enable the growth of stable 2D halide perovskite heterostructures. In this study, we present an innovative polymer bridging strategy for the preparation of 2D halide perovskite lateral heterostructures with enhanced stability. We selected a linear polymer with cyano as the polymer bridge. The Polymers contain a significant number of binding sites that can effectively coordinate with the uncoordinated lead atoms at the in-plane edge of the 2D halide perovskite, thereby providing protection against perovskite decomposition. Additionally, the coordination of the polymer results in a heightened binding energy of Pb, leading to stronger halide ion binding and subsequent inhibition of halide ion migration. As a result, we demonstrate highly thermal stability of the heterostructure. Furthermore, the heterostructure exhibits the biexciton luminescence behaviors without the high energy excitation light. These findings present an effective approach for fabricating robust 2D halide perovskite lateral heterostructures. This research contributes to the advancement of the field by providing a new concept for fabricating stable 2D halide perovskite lateral heterostructures, and by offering significant insights into anionic behavior within such heterostructures.

Two-dimensional (2D) MXenes have emerged as promising candidates to serve as Schottky contact electrodes for the development of high-performance photodiodes owing to their extraordinary electronic properties. However, it remains a formidable challenge to fabricate a large-area, uniform MXene layer for practical device application. Here, we develop a facile route to produce a large-area Ti3C2Tx layer by post-etching treatment of a pulsed laser-deposited Ti3AlC2 film, enabling the in situ construction of a back-illuminated Ti3C2Tx/n-Si Schottky-barrier photodiode. Significantly, the device exhibits excellent performance with a distinctive self-filtered near-infrared (NIR) photoresponse behavior in the range of 700-1100 nm. By avoiding disturbances caused by ambient light, the NIR photodiode-based transmission-type photoplethysmographic (PPG) measurement system is capable of more reliable detection of PPG waveforms than the commercial PPG sensors for continuously monitoring heart rate. This enables the accurate extraction of blood pressures using a PPG-only method. Our findings not only pave the way for fabrication of a high-quality large-area 2D MXene layer, but also provide a general design principle for developing high-performance MXene/Si photodiodes for health monitoring systems.

Wafer-sized two-dimensional Ruddlesden-Popper perovskite single-crystal thin films (SCTFs) hold immense potential as alternatives for fabricating large-scale optoelectronic devices and are anticipated to achieve commercial application in technologies such as high-performance micro-PeLEDs and integrated panels for advanced displays of the future. However, wafer-sized growth of perovskite single-crystal films remains challenging, primarily attributed to the inherent difficulties in controlling the nucleation process and managing the anisotropic growth behavior. These factors lead to rapid nucleation rate and high nucleation density, which impede crystal wafer-sized growth. Herein, we design a polymer-linked assistance strategy to grow wafer-sized BA2PbBr4(BA=CH3CH2CH2CH2NH3+) SCTFs. The coordination interaction between the polymers containing oxygen functional groups and lead ions enhances solution stability, reducing nucleation density and increasing nucleation size. Additionally, the polymers adsorb onto inorganic layers through coordination interaction, suppressing vertical crystal growth while promoting preferential lateral orientation. These mechanisms collectively facilitate the growth of wafer-sized, high-quality BA2PbBr4SCTFs. This strategy yields high-quality BA2PbBr4SCTFs with lateral dimension of 50.0 mm and thickness of 470.8 nm, representing a high aspect ratio more than 105. The defects in BA2PbBr4SCTFs are suppressed by the coordination interaction between functional groups and lead ions. This work not only establishes a feasible strategy for wafer-sized growth of high-quality halide perovskite SCTFs, but also paves the way for their practical implementation in next-generation optoelectronic devices.

Intrinsically stretchable organic solar cells (IS-OSCs) are highly promising for next-generation wearable electronics. The incorporation of thermoplastic elastomers (TPEs) provides a cost-effective strategy to improve mechanical compliance. However, the influence of TPE structural diversity on device performance has been largely overlooked. In this work, the concept of effective elastomer density (De) is introduced as a unified molecular descriptor to quantitatively evaluate how elastomer structures affect IS-OSC morphology and functionality. It is demonstrated that increasing De enhances stretchability by inducing domain coarsening and surface roughening in amorphous regions, but simultaneously prolongs exciton lifetimes and suppresses charge extraction and transport. Notably, IS-OSCs achieve an optimal balance at a critical De of 1.5 mol m-3, delivering a high initial power conversion efficiency (PCE) of 14.3% and retaining 80% of the initial PCE at 30.6% strain, representing the best performance reported to date for IS-OSCs employing the elastomer-plasticization strategy. This descriptor-based framework provides a predictive and generalizable guideline for the molecular design of elastomers in stretchable optoelectronic devices.

A three-dimensional host architecture has emerged as a promising strategy for developing high-energy lithium metal anodes, where the lithiophilic characteristics and interfacial compatibility of the host material play pivotal roles in determining the electrochemical performance. In this work, we demonstrate an innovative gas plasma-assisted technique for in situ synthesis of NiF2 coatings on nickel fiber current collectors. The three-dimensional interconnected NiF2-modified Ni fiber network not only provides efficient electron transport pathways but also enables homogeneous lithium-ion flux distribution, synergistically reducing local current density and alleviating volume changes during cycling. The NiF2-modified Ni fiber/lithium metal anode (Li/FN) achieves a low overpotential of 16.7 mV for 2600 h at a current density of 1 mA cm-2 with a high average Coulombic efficiency of 99.1%, showing a marked improvement over its unmodified counterpart. When paired with LiN0.8Co0.1Mn0.1O2 (NCM811) cathodes, the assembled full cells exhibit a capacity retention rate of 85.2% after 100 cycles at 0.5 C. This plasma-enabled surface engineering approach presents a scalable and efficient pathway for fabricating high-performance lithium metal anodes, offering new insights into interface optimization strategies for next-generation battery systems.

Metal halide perovskites (MHPs) show optoelectronic properties that are highly advantageous for light-emitting applications. Compared to polycrystalline (PC) perovskite, single-crystal (SC) perovskite exhibits high carrier mobility, reducing ion migration and suppressing Auger recombination. However, SC perovskite light-emitting diodes (SC-PeLEDs) face the following challenges: i) the growth of high-aspect-ratio SC films; ii) the interfacial contact between the SC light-emitting layers and the carrier transport layers. This review begins with the growth methods of MHP SC thin films. Then, the recent research progress of SC-PeLEDs is summarized, and the strategies for optimizing device performance are also reviewed. Finally, perspectives are proposed further to enhance the performance and practical application of SC-PeLEDs.

The nickel oxide (NiOx) film is often employed as a hole transport layer for the production of high-performance inverted perovskite solar cells due to its exceptional chemical stability, high hole mobility, and matching energy level structure. Among various techniques for preparing NiOx, E-beam evaporation-based NiOx films show great promise owing to their low fabrication temperature and excellent photoelectric properties. Herein, an ion bombardment source was used to generate oxygen plasma through the bombardment of oxygen molecules, which subsequently oxidized the non-stoichiometric NiOx. Experimental findings demonstrate that this method substantially enhances the electrical and optical properties of the NiOx film. We utilized a room-temperature-processed NiOx film as a hole transport layer to fabricate inverted wide-bandgap perovskite solar cells, resulting in a champion device efficiency of 17.82%. It is anticipated that the NiOx films produced via this approach will be widely adopted in the industrialization of perovskite solar cells.

Epitaxial growth stands as a key method for integrating semiconductors into heterostructures, offering a potent avenue to explore the electronic and optoelectronic characteristics of cutting-edge materials, such as transition metal dichalcogenide (TMD) and perovskites. Nevertheless, the layer-by-layer growth atop TMD materials confronts a substantial energy barrier, impeding the adsorption and nucleation of perovskite atoms on the 2D surface. Here, we epitaxially grown an inorganic lead-free perovskite on TMD and formed van der Waals (vdW) heterojunctions. Our work employs a monomolecular membrane-assisted growth strategy that reduces the contact angle and simultaneously diminishing the energy barrier for Cs3Sb2Br9 surface nucleation. By controlling the nucleation temperature, we achieved a reduction in the thickness of the Cs3Sb2Br9 epitaxial layer from 30 to approximately 4 nm. In the realm of inorganic lead-free perovskite and TMD heterojunctions, we observed long-lived interlayer exciton of 9.9 ns, approximately 36 times longer than the intralayer exciton lifetime, which benefited from the excellent interlayer coupling brought by direct epitaxial growth. Our research introduces a monomolecular membrane-assisted growth strategy that expands the diversity of materials attainable through vdW epitaxial growth, potentially contributing to future applications in optoelectronics involving heterojunctions.

The investigation on the free motion of nanoparticles and their interaction with other media has become an attrac-tive field for extending the practical application.However,the real-time monitoring of dynamic behaviors still exists signifi-cant challenge.In this paper,based on surface enhanced Raman spectroscopy(SERS)and the formation of"hot spots"during collision between Au nanoparticles and Au single crystal microplate under Brownian motion,the real-time monitoring of free motion behaviors of Au nanoparticles during collision and the dynamic SERS study were realized accordingly by using thio-phenol(TP)as the probe molecule.The nature and influencing factors of microscopic motion of nanoparticles were investi-gated by statistical analysis of the"spikes"in the SERS trajectories,including"single spikes"and"cluster spikes".The re-sults reveal that the"spike"is mainly attributed to the"hot spots"formed by reversible collision of nanoparticle and plane."Single spikes"correspond to the rapid departure of Au nanoparticles from the surface of the Au microplate after collision with the microplate,and"cluster spikes"correspond to the process of Au nanoparticles staying on the surface of the Au mi-croplate for a short time after colliding with the plane and then leaving or possibly multiple nanoparticles colliding continu-ously.Increasing the concentration of nanoparticles is beneficial to the formation of"cluster spike".The intensity distribution of the corresponding SERS characteristic peaks is concentrated in 5.2 cps and 8.7 cps,respectively.The relative intensities of SERS peaks of TP in the"spikes"are critically depended on the vibrational modes.It demonstrates that the probability of stretching vibrational modes is higher,and it is mainly due to the different orientations of molecules in the localized area during the dynamic collision processes.The realization of dynamic collision is beneficial to deeply understand the nature of microscopic motion of nanoparticles.It provides the basis for the investigation of dynamic interfacial chemical reactions in localized area.

Thermochromic perovskites, renowned for their tunable bandgap, high absorption coefficient, and reversible color changes, emerge as promising candidates for applications in smart windows. These advancements not only have the potential to enhance occupant comfort but also contribute significantly to reducing energy consumption in buildings. Here, we present a two-dimensional lead-free organic-inorganic hybrid perovskite [Cyclobutylammonium]2CuCl4 which shows phase transitions from C2/c to P21/c to P21/c space group at 319.5 K and 348.8 K, respectively. Accompanying these transitions is a fascinating, reversible thermochromic behavior that is dependent on the phase structure. This behavior manifests as a vibrant sequence transitioning from yellow to brown and finally to a slightly dark brown. Most importantly, the demonstrated ability to switch stably between high and low dielectric states indicates the enormous potential of this material as a dielectric switch. This non-toxic thermoresponsive perovskite, characterized by its appropriate transition temperatures, reversible phase structure-dependent thermochromism, and stable dielectric switching behavior, is expected to generate significant interest within the fields of thermoresponsive and dielectric switching materials. The integration of these features not only positions this perovskite as a noteworthy subject of scientific inquiry but also opens avenues for practical applications in diverse fields. This manuscript reports two-dimensional lead-free organic-inorganic hybrid perovskite [Cyclobutylammonium]2CuCl4. It demonstrates compelling features, including distinct phase transitions, thermochromic properties, and stable dielectric switching behavior. Its combination of non-toxicity and functional attributes makes it a promising candidate for further exploration and application in the fields of thermoresponsive and dielectric switching materials.+ image