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Lead‐based halide perovskites have gained significant prominence in recent years in optoelectronics and photovoltaics, owing to their exceptional optoelectronic properties. Nonetheless, the toxicity of lead (Pb) and the stability concern pose obstacles to their potential for future large‐scale market development. Herein, stable lead‐free Cs3Bi2I9 (CBI) films are presented with smooth and compact morphologies synthesized via chemical vapor deposition (CVD), demonstrating their application as an UV photodetector in a self‐powered way. The self‐powered photodetectors (SPDs) exhibit remarkable characteristics, including a responsivity of 1.57 A W−1 and an impressive specific detectivity of 3.38 × 1013 Jones under the illumination of 365 nm at zero bias. Furthermore, the SPDs exhibit a nominal decline (≈2.2%) in the photocurrent under constant illumination over 500 h, highlighting its impressive long‐term operational stability. Finally, the real‐time UV‐detection capability of the device is demonstrated by measuring the photocurrent under various conditions, including room light and sunlight at different times. These findings offer a new platform for synthesizing stable and high‐quality perovskite films, and SPDs for advancing the development of wearable and portable electronics. [ABSTRACT FROM AUTHOR]

In this study, a mechanically flexible structure, a cuboctahedral metal‐organic polyhedra (MOP) Cu24[5‐(octyloxy) isophthalic acid]24 Cu (II) paddlewheel clusters coordinated with (5‐(octyloxy) isophthalate), resulting in significantly enhanced hydrolytic stability are prepared. It should be noted that CuMOP‐1 exhibits evenly and symmetrically distributed non‐polar long alkyl chains and polar hydroxy groups, facilitating self‐assembly into higher‐order structures reminiscent of amphiphiles. Furthermore, the resultant CuMOP‐1 undergoes a phase change at 150–160 °C as confirmed temperature‐dependent Raman spectroscopy (RS), thermogravimetric analysis and Differential Scanning Calorimetry (TGA‐DSC). The possible use of Cu‐MOP‐1 for capturing mechanical energy is demonstrated by creating a flexible hybrid piezoelectric‐triboelectric nanogenerator (HP‐TENG). The resultant CuMOP‐1@ Polyvinylidene fluoride(PVDF) membrane‐based HP‐TENG demonstrates enhanced triboelectric output voltage of 547.5 V, current density of 15.16 µAcm−2, and power density of 2.8 mWcm−2 due to its increased surface charge density and a substantial rise in the dielectric constant. Furthermore, the amphiphiles and phase change in CuMOP‐1 lead to ∽73% increase in voltage and 60% in current density of HP‐TENG in high‐temperature (140 °C) environments. HP‐TENG also exhibits exceptional temperature‐ and pressure‐sensing abilities, with sensitivities of 1.81 V°C−1 and 7.12 V°kPa−1, respectively, showcasing its feasibility over a wide range of temperatures and pressures. [ABSTRACT FROM AUTHOR]

Due to a rise in industrial pollutants in modern life, the climate and energy crisis have grown more widespread. One of the best ways to deal with dye degradation, hydrogen production, and carbon dioxide reduction issues is the photocatalytic technique. Among various methods, catalytic technology has demonstrated tremendous promise in recent years as a cheap, sustainable, and environmentally benign technology. The expeditious establishment of carbon-based metal nanoparticles as catalysts in the disciplines of materials and chemical engineering for catalytic applications triggered by visible light is largely attributed to their advancement. There have been many wonderful catalysts created, but there are still many obstacles to overcome, which include the cost of catalysts being reduced and their effectiveness being increased. Carbon-based materials exhibit a unique combination of characteristics that make them ideal catalysts for various reaction types. These characteristics include an exceptional electrical conductivity, well-defined structures at the nanoscale, inherent water repellency, and the ability to tailor surface properties for specific applications. This versatility allows them to be effective in diverse catalytic processes, encompassing organic transformations and photocatalysis. The emergence of carbon-based nanostructured materials, including fullerenes, carbon dots, carbon nanotubes, graphitic carbon nitride, and graphene, presents a promising alternative to conventional catalysts. This review focuses on the diverse functionalities of these materials within the realm of catalysis materials for degradation, hydrogen production, and carbon dioxide reduction. Additionally, it explores the potential for their commercialization, delving into the underlying mechanisms and key factors that influence their performance. It is anticipated that this review will spur more research to develop high-performance carbon-based materials for environmental applications. [ABSTRACT FROM AUTHOR]

Perovskite solar cells typically comprise electron- and hole-transport materials deposited on each side of a perovskite active layer. So far, only two organic hole-transport materials have led to state-of-the-art performance in these solar cells.sup.1: poly(triarylamine) (PTAA).sup.2-5 and 2,2E,7,7E-tetrakis(N,N-di-p-methoxyphenylamine)-9,9E-spirobifluorene (spiro-OMeTAD).sup.6,7. However, these materials have several drawbacks in terms of commercialization, including high cost.sup.8, the need for hygroscopic dopants that trigger degradation of the perovskite layer.sup.9 and limitations in their deposition processes.sup.10. Poly(3-hexylthiophene) (P3HT) is an alternative hole-transport material with excellent optoelectronic properties.sup.11-13, low cost.sup.8,14 and ease of fabrication.sup.15-18, but so far the efficiencies of perovskite solar cells using P3HT have reached only around 16 per cent.sup.19. Here we propose a device architecture for highly efficient perovskite solar cells that use P3HT as a hole-transport material without any dopants. A thin layer of wide-bandgap halide perovskite is formed on top of the narrow-bandgap light-absorbing layer by an in situ reaction of n-hexyl trimethyl ammonium bromide on the perovskite surface. Our device has a certified power conversion efficiency of 22.7 per cent with hysteresis of [plus or minus]0.51 per cent; exhibits good stability at 85 per cent relative humidity without encapsulation; and upon encapsulation demonstrates long-term operational stability for 1,370 hours under 1-Sun illumination at room temperature, maintaining 95 per cent of the initial efficiency. We extend our platform to large-area modules (24.97 square centimetres)--which are fabricated using a scalable bar-coating method for the deposition of P3HT--and achieve a power conversion efficiency of 16.0 per cent. Realizing the potential of P3HT as a hole-transport material by using a wide-bandgap halide could be a valuable direction for perovskite solar-cell research. A double-layered halide architecture for perovskite solar cells enables the use of dopant-free poly(3-hexylthiophene) as a hole-transport material, forming stable and scalable devices with a certified power conversion efficiency of 22.7 per cent., Author(s): Eui Hyuk Jung [sup.1] , Nam Joong Jeon [sup.1] , Eun Young Park [sup.1] , Chan Su Moon [sup.1] [sup.2] , Tae Joo Shin [sup.3] , Tae-Youl Yang [sup.1] [...]

Abstract: The stability of a perovskite solar cell (PSC) is enhanced significantly by applying a customized thin‐film encapsulation (TFE). The TFE is composed of a multilayer stack of organic/inorganic layers deposited by initiated chemical vapor deposition and atomic layer deposition, respectively, whose water vapor transmission rate is on the order of 10−4 g m−2 d−1 at an accelerated condition of 38 °C and 90% relative humidity (RH). The TFE is optimized, taking into consideration various aspects of thermosensitive PSCs. Lowering the process temperature is one of the most effective methods for minimizing the thermal damage to the PSC during the monolithic integration of the TFE onto PSC. The direct deposition of TFE onto a PSC causes less than 0.3% degradation (from 18.5% to 18.2%) in the power conversion efficiency, while the long‐term stability is substantially improved; the PSC retains 97% of its original efficiency after a 300 h exposure to an accelerated condition of 50 °C and 50% RH, confirming the enhanced stability of the PSC against moisture. This is the first demonstration of a TFE applied directly onto PSCs in a damage‐free manner, which will be a powerful tool for the development of highly stable PSCs with high efficiency. [ABSTRACT FROM AUTHOR]