Tin halide perovskite (THP) has emerged as a promising lead-free material for high-performance solar cells, attracting significant attention for their potential use for energy conversion. However, the rapid crystallization of THP due to its high Lewis acidity and easy oxidation of Sn leads to poor morphology and rampant defects in the resulting perovskite films. These strongly hamper the advances in efficiency and stability in THP solar cells.
View Article and Find Full Text PDFHydrophobic ionic liquid (HIL) engineering on the catalyst surface represents a simple yet potent direction for optimizing the CO electroreduction performance. However, the pivotal role of HIL engineering at an industrial current density is still ambiguous due to limited and conflicting research findings. Herein, HIL-engineered oxide-derived Cu porous nanoparticles with electron-delocalized groups and a specific ultramicropore structure are first constructed to facilitate CO-to-C electroreduction at ampere-level current densities.
View Article and Find Full Text PDFContinuous breakthroughs have been achieved in the photoelectric conversion efficiency (PCE) of tin-based perovskite solar cells (TPSCs) in recent years. Inspired by performance improvements observed during device storage, we identified beneficial light-induced interface doping (LIID) in the TPSCs. In situ analyses using X-ray photoelectron spectroscopy and ultraviolet photoelectron spectroscopy reveal that ion migration and oxidation at the interface induce beneficial doping effects, enhancing carrier transport and significantly boosting device performance.
View Article and Find Full Text PDFBreaking the thermal, mechanical and lightweight performance limit of aerogels has pivotal significance on thermal protection, new energy utilization, high-temperature catalysis, structural engineering, and physics, but is severely limited by the serious discrete characteristics between grain boundary and nano-units interfaces. Herein, a thermodynamically driven surface reaction and confined crystallization process is reported to synthesize a centimeter-scale supercontinuous ZrO nanolayer on ZrO-SiO fiber aerogel surface, which significantly improved its thermal and mechanical properties with density almost unchanged (≈26 mg cm). Systematic structure analysis confirms that the supercontinuous layer achieves a close connection between grains and fibers through Zr─O─Si bonds.
View Article and Find Full Text PDFPhotocatalytic oxidative coupling of methane (OCM) offers an appealing route for converting greenhouse gas into valuable C hydrocarbons. However, O as the most commonly used oxidant, tends to result in inevitable overoxidation and waste of methane feedstock. Herein, we first report a photocatalytic OCM using CO as a soft oxidant for CH production under mild conditions, where an efficient photocatalyst with unique interface sites is designed and constructed to facilitate CO adsorption and activation, while concurrently boosting CH dissociation.
View Article and Find Full Text PDFAlkali element doping has significant physical implications for two-dimensional materials, primarily by tuning the electronic structure and carrier concentration. It can enhance interface electronic interactions, providing opportunities for effective charge transfer at metal-organic interfaces. In this work, we investigated the effects of gradually increasing the level of K doping on the lattice structure and electronic properties of an organometallic coordinated Kagome lattice on a Ag(111) surface.
View Article and Find Full Text PDFBranched alkanes, which enhance the octane number of gasoline, can be produced from waste polyethylene. However, achieving highly selective production of branched alkanes presents a significant challenge in the upcycling of waste polyethylene. Here, we report a one-pot process to convert polyethylene into gasoline-range hydrocarbons (C-C) with yield of 73.
View Article and Find Full Text PDFThe recent developed bottom-up on-surface synthesis offers unprecedent opportunities for the fabrication of two-dimensional (2D) carbon-based networks with atomic precision. Hierarchical coupling approach has been proposed as an efficient strategy for improving the corresponding reaction selectivity and quality of target structures. Herein, we report the synthesis of a nitrogen-doped carbon-based network on Ag(100) utilizing a hierarchical Ullmann coupling strategy.
View Article and Find Full Text PDFSoft X-ray imaging is a powerful tool to explore the structure of cells, probe material with nanometer resolution, and investigate the energetic phenomena in the universe. Conventional soft X-ray image sensors are by and large Si-based charge coupled devices that suffer from low frame rates, complex fabrication processes, mechanical inflexibility, and required cooling below -60 °C. Here, a soft X-ray photodiode is reported based on low-cost metal halide perovskite with comparable performance to commercial Si-based device.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2024
Free of posttransfer, on-surface synthesis (OSS) of single-atomic-layer nanostructures directly on semiconductors holds considerable potential for next-generation devices. However, due to the high diffusion barrier and abundant defects on semiconductor surfaces, extended and well-defined OSS on semiconductors has major difficulty. Furthermore, given semiconductors' limited thermal catalytic activity, initiating high-barrier reactions remains a significant challenge.
View Article and Find Full Text PDFNanoporous graphene (NPG) materials are generated by removing internal degree-3 vertices from graphene and introducing nanopores with specific topological structures, which have been widely explored and exploited for applications in electronic devices, membranes, and energy storage. The inherent properties of NPGs, such as the band structures, field effect mobilities and topological properties, are crucially determined by the geometric structure of nanopores. On-surface synthesis is an emerging strategy to fabricate low-dimensional carbon nanostructures with atomic precision.
View Article and Find Full Text PDFPhosphorene and fullerene are representative two-dimensional (2D) and zero-dimensional (0D) nanomaterials respectively, constructing their heterodimensional hybrid not only complements their physiochemical properties but also extends their applications via synergistic interactions. This is however challenging because of their diversities in dimension and chemical reactivity, and theoretical studies predicted that it is improbable to directly bond C onto the surface of phosphorene due to their strong repulsion. Here, we develop a facile electrosynthesis method to synthesize the first phosphorene-fullerene hybrid featuring fullerene surface bonding via P-C bonds.
View Article and Find Full Text PDFWhile the monolayer sheet is well-established as a Mott-insulator with a finite energy gap, the insulating nature of bulk 1T-TaS crystals remains ambiguous due to their varying dimensionalities and alterable interlayer coupling. In this study, we present a unique approach to unlock the intertwined two-dimensional Mott-insulator and three-dimensional band-insulator states in bulk 1T-TaS crystals by structuring a laddering stack along the out-of-plane direction. Through modulating the interlayer coupling, the insulating nature can be switched between band-insulator and Mott-insulator mechanisms.
View Article and Find Full Text PDFP-type self-doping is known to hamper tin-based perovskites for developing high-performance solar cells by increasing the background current density and carrier recombination processes. In this work, we propose a gradient homojunction structure with germanium doping that generates an internal electric field across the perovskite film to deplete the charge carriers. This structure reduces the dark current density of perovskite by over 2 orders of magnitude and trap density by an order of magnitude.
View Article and Find Full Text PDFPhotocatalytic conversion of methane (CH) to ethane (CH) has attracted extensive attention from academia and industry. Typically, the traditional oxidative coupling of CH (OCM) reaches a high CH productivity, yet the inevitable overoxidation limits the target product selectivity. Although the traditional nonoxidative coupling of CH (NOCM) can improve the product selectivity, it still encounters unsatisfied activity, arising from being thermodynamically unfavorable.
View Article and Find Full Text PDFStructure-optimized bimetallic and multicomponent catalysts often outperform single-component catalysts, inspiring a detailed investigation of metal-metal and metal-support interactions in the system. We investigated the geometric and electronic structures of ceria-supported Ni-Cu particles prepared using different metal deposition sequences employing a combination of X-ray photoelectron spectroscopy, resonant photoemission spectroscopy, and infrared reflection absorption spectroscopy. The bimetallic model catalyst structure was altered by a distinct surface evolution process determined by the metal deposition sequence.
View Article and Find Full Text PDFHigh-quality perovskite films are essential for achieving high performance of optoelectronic devices; However, solution-processed perovskite films are known to suffer from compositional and structural inhomogeneity due to lack of systematic control over the kinetics during the formation. Here, the microscopic homogeneity of perovskite films is successfully enhanced by modulating the conversion reaction kinetics using a catalyst-like system generated by a foaming agent. The chemical and structural evolution during this catalytic conversion is revealed by a multimodal synchrotron toolkit with spatial resolutions spanning many length scales.
View Article and Find Full Text PDFTargeted synthesis of acetic acid (CH COOH) from CO photoreduction under mild conditions mainly limits by the kinetic challenge of the C-C coupling. Herein, we utilized doping engineering to build charge-asymmetrical metal pair sites for boosted C-C coupling, enhancing the activity and selectivity of CO photoreduction towards CH COOH. As a prototype, the Pd doped Co O atomic layers are synthesized, where the established charge-asymmetrical cobalt pair sites are verified by X-ray photoelectron spectroscopy and X-ray absorption near edge spectroscopy spectra.
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