Precision Chemistry最新文献

Hydrogen economy, which proposes employing hydrogen to replace or supplement the current fossil-fuel-based energy economy system, is widely accepted as the future energy scheme for the sustainable and green development of human society. While the hydrogen economy has shown tremendous potential, the associated challenges with hydrogen production and storage remain significant barriers to wide applications. In light of this consideration, the integration of green hydrogen production and storage through electrocatalysis for direct production of chemical hydrogen storage media has emerged as a potential solution to these challenges. Specifically, through electrocatalysis, CO₂ and H₂O can be converted into methanol or formic acid, while N₂ or NO_x along with H₂O can be transformed into ammonia, streamlining the hydrogen economy scheme. In this Perspective, we provide an overview of recent developments in this technology. Additionally, we briefly discuss the general properties and corresponding production strategies via the electrolysis of these chemical hydrogen storage media. Finally, we conclude by offering insights into future perspectives in this field, anticipating that the successful advancement of such technology will propel the development of the hydrogen economy toward practical implementation.

Emerging monolayer molecular crystals (MMCs) have become prosperous in recent decades due to their numerous advantages. First, downsizing the active layer thickness to monolayer in organic field-effect transistors (OFETs) is beneficial to elucidate the intrinsic charge-transport behavior. Next, the ultrathin conducting channel can reduce bulk injection resistance to extract mobility accurately. Then, direct exposure of the conducting channel can enhance the sensing performance. Finally, MMCs combine the merits of ultrathin thickness and high crystallization, which will improve the optoelectronic performance and realize complex device architectures for future advanced optoelectronic applications. In this Review, recent research progress in precise preparations and advanced applications of solution-processed MMCs are summarized. We present the current challenges related to MMCs with specific structures and desired performances, and an outlook regarding their application in next-generation integrated organic optoelectronics is provided.

The catalytic asymmetric diastereodivergent synthesis of axially chiral 2-alkenylindoles was established via chiral phosphoric acid-catalyzed addition reactions of C3-unsubstituted 2-alkenylindoles with o-hydroxybenzyl alcohols under different reaction conditions. Using this strategy, two series of 2-alkenylindoles bearing both axial and central chirality were synthesized in a diastereodivergent fashion with moderate to high yields and good stereoselectivities (up to 99% yield, 95:5 er, >95:5 dr). Moreover, theoretical calculations were performed on the key transition states leading to different stereoisomers, which provided an in-depth understanding of the origin of the observed stereoselectivity and diastereodivergence of the products under different reaction conditions. More importantly, these 2-alkenylindoles were utilized in asymmetric catalysis as chiral organocatalysts and in medicinal chemistry for evaluation of their cytotoxicity, which demonstrated their potential applications. This study has not only established the catalytic atroposelective synthesis of axially chiral 2-alkenylindoles, but also provided an efficient strategy for catalytic asymmetric diastereodivergent construction of indole-based scaffolds bearing both axial and central chirality.

To develop porous organic frameworks, precise control of the stacking manner of two-dimensional porous motifs and structural characterization of the resultant framework are important. From these points of view, porous molecular crystals formed through reversible intermolecular hydrogen bonds, such as hydrogen-bonded organic frameworks (HOFs), can provide deep insight because of their high crystallinity, affording single-crystalline X-ray diffraction analysis. In this study, we demonstrate that the stacking manner of hydrogen-bonded hexagonal network (HexNet) sheets can be controlled by synchronizing a homological triangular macrocyclic tecton and a hydrogen-bonded cyclic supramolecular synthon called the phenylene triangle. A structure of the resultant HOF was crystallographically characterized and revealed to have a large channel aperture of 2.4 nm. The HOF also shows thermal stability up to 290 °C, which is higher than that of the conventional HexNet frameworks.

Graphdiyne (GDY) science is a new and rapidly developing interdisciplinary field that touches on various areas of chemistry, physics, information science, material science, life science, environmental science, and so on. The rapid development of GDY science is part of the trend in development of carbon materials. GDY, with its unique structure and fascinating properties, has greatly promoted fundamental research toward practical applications of carbon materials. Many important applications, such as catalysis and energy conversion, have been reported. In particular, GDY has shown great potential for application in the field of catalysis. Scientists have precisely synthesized a series of GDY-based multiscale catalysts and applied them in various energy conversion and catalysis research, including ammonia synthesis, hydrogen production, CO₂ conversion, and chemical-to-electrical energy conversion. In this paper, we systematically review the advances in the precisely controlled synthesis of GDY and aggregated structures, and the latest progress with GDY in catalysis and energy conversion.

To rationalize the design of D-π-A type organic small-molecule nonlinear optical materials, a theory guided machine learning framework is constructed. Such an approach is based on the recognition that the optical property of the molecule is predictable upon accumulating the contribution of each component, which is in line with the concept of group contribution method in thermodynamics. To realize this, a Lewis-mode group contribution method (LGC) has been developed in this work, which is combined with the multistage Bayesian neural network and the evolutionary algorithm to constitute an interactive framework (LGC-msBNN-EA). Thus, different optical properties of molecules are afforded accurately and efficiently─by using only a small data set for training. Moreover, by employing the EA model designed specifically for LGC, structural search is well achievable. The origins of the satisfying performance of the framework are discussed in detail. Considering that such a framework combines chemical principles and data-driven tools, most likely, it will be proven to be rational and efficient to complete mission regarding structure design in related fields.

Among the various two-dimensional (2D) materials, more than 99% of them are noncentrosymmetric. However, since the commonly used substrates are generally centrosymmetric, antiparallel islands are usually inevitable in the growth of noncentrosymmetric 2D materials because of the energetic equivalency of these two kinds of antiparallel islands on centrosymmetric substrates. Therefore, achieving the growth of noncentrosymmetric 2D single crystals has long been a great challenge compared with the centrosymmetric ones like graphene. In this review, we presented the remarkable efforts and progress in the past decade, through precise chemical processes. We first discussed the great challenge and possible strategies in the growth of noncentrosymmetric 2D single crystals. Then, we focused on the advancements made in producing representative noncentrosymmetric 2D single crystals, including hexagonal boron nitride (hBN), transition metal dichalcogenides (TMDs), and other noncentrosymmetric 2D materials. At last, we summarized and looked forward to future research on the growth of layer-, stacking-, and twist-controlled noncentrosymmetric 2D single crystals and their heterostructures.