Chemical Science

doi: 10.1039/d4sc90200apmid: N/A

doi: 10.1039/d4sc90201gpmid: N/A

doi: 10.1039/d4sc90202epmid: N/A

Yan, Maximilian; Martell, Sarah; Patwardhan, Siddharth V.; Dasog, Mita

doi: 10.1039/d4sc04065apmid: 39309091

Porous Si (p-Si) nanomaterials are an exciting class of inexpensive and abundant materials within the field of energy storage. Specifically, p-Si has been explored in battery anodes to improve charge storage capacity, to generate clean fuels through photocatalysis and photoelectrochemical processes, for the stoichiometric conversion of CO2 to value added chemicals, and as a chemical H2 storage material. p-Si can be made from synthetic, natural, and waste SiO2 sources through a facile and inexpensive method called magnesiothermic reduction (MgTR). This yields a material with tunable properties and excellent energy storage capabilities. In order to tune the physical properties that affect performance metrics of p-Si, a deeper understanding of the mechanism of the MgTR and factors affecting it is required. In this perspective, we review the key developments in MgTR and discuss the thermal management strategies used to control the properties of p-Si. Additionally, we explore future research directions and approaches to bridge the gap between laboratory-scale experiments and industrial applications.

Shioi, Ryuta; Kool, Eric T.

doi: 10.1039/d4sc05317fpmid: 39309104

Electrophilic water-soluble compounds have proven versatile in reacting selectively with 2′-OH groups in RNA, enabling structure mapping, probing, caging, labeling, crosslinking, and conjugation of RNAs in vitro and in living cells. While early work focused on one or two types of reagents with limited properties, recent studies have greatly diversified the structure, properties, and applications of these reagents. Here we review the scope of documented RNA hydroxyl-reactive species reported to date, with an eye to the effects of chemical structure on reactivity with RNA and other useful properties. Multiple forms of carbonyl electrophiles are now known to react at the 2′-OH, and recently, sulfonyl and aryl electrophiles have also been documented to form bonds there in high yields as well. In addition to electrophilicity, data also point to significant effects of reagent stability, steric bulk, and chirality on reaction yields and selectivity. Finally, we outline reagent properties and principles that define utility in applications with RNA, with an eye to the design of future reagents.

Gu, Hao; Zhang, Tianshuo; Wang, Yunluo; Zhou, Tianrui; Chen, Haijie

doi: 10.1039/d4sc03428gpmid: 39328196

Compounds with heterolayered architecture, as a family of two-dimensional (2D) materials, are composed of alternating positive and negative layers. Their physical properties are determined not only by the charged constituents, but also by the interaction between the two layers. This kind of material has been widely used for superconductivity, thermoelectricity, energy storage, etc. In recent years, heterolayered compounds have been found as an encouraging choice for infrared photodetectors with high sensitivity, fast response, and remarkable reliability. In this review, we summarize the research progress of heterolayered materials for infrared photodetectors. A simple development history of the materials with three-dimensional (3D) or 2D structures, which are suitable for infrared photodetectors, is introduced firstly. Then, we compare the differences between van der Waals layered 2D materials and heterolayered 2D cousins and explain the advantages of heterolayered 2D compounds. Finally, we present our perspective on the future direction of heterolayered 2D materials as an emerging class of materials for infrared photodetectors.

Boeck, Parker T.; Veige, Adam S.

doi: 10.1039/d4sc04243cpmid: 39345778

Cyclic polymers have applications across various fields, including material science, biomedicine, and inorganic chemistry. Cyclic polymers derived from alkyne monomers have expanded the application scope to include electronic materials and polyolefins. This review highlights recent advancements in the synthesis of cyclic polymers from both mono- and disubstituted alkynes. The aim is to provide a comprehensive overview of the synthetic methodologies and the application of cyclic polymers derived from alkynes. Additionally, this review will facilitate a comparative analysis of the advantages and limitations of various synthetic methods and describe opportunities for future development of novel catalytic systems to synthesize cyclic polymers from alkynes.

Vinod, Kavya; Mathew, Renny; Jandl, Christian; Thomas, Brijith; Hariharan, Mahesh

doi: 10.1039/d4sc05453apmid: 39345764

Eumelanin, a versatile biomaterial found throughout the animal kingdom, performs essential functions like photoprotection and radical scavenging. The diverse properties of eumelanin are attributed to its elusive and heterogenous structure with DHI (5,6-dihydroxyindole) and DHICA (5,6-dihydroxyindole-2-carboxylic acid) precursors as the main constituents. Despite DHICA being recognized as the key eumelanin precursor, its crystal structure and functional role in the assembled state remain unknown. Herein, we employ a synthesis-driven, bottom-up approach to elucidate the structure and assembly-specifics of DHICA, a critical building block of eumelanin. We introduce an interdisciplinary methodology to analyse the nanocrystalline assembly of DHICA, employing three-dimensional electron diffraction (3D ED), solid-state NMR and density functional theory (DFT), while correlating the structural aspects with the electronic spectroscopic features. The results underscore charge-transfer exciton delocalization as the predominant energy transfer mechanism within the π–π stacked and hydrogen-bonded crystal network of DHICA. Additionally, extending the investigation to the 13C-labelled DHICA-based polymer improves our understanding of the chemical heterogeneity across the eumelanin pigment, providing crucial insights into the structure of eumelanin.

Kaiya, Kyohei; Ueki, Yoshiya; Kawamoto, Hiromasa; Watanabe, Kenta; Yoshino, Shunya; Yamaguchi, Yuichi; Kudo, Akihiko

doi: 10.1039/d4sc03978epmid: 39290591

Highly efficient water splitting under visible light irradiation was achieved using Ir, Sb, and Al-codoped SrTiO3 of a single particulate metal oxide photocatalyst by a solid-state reaction followed by flux treatment using SrCl2 and loading of a RhCrOx cocatalyst. The photocatalytic activity was improved by Al2O3 addition to the flux treatment, and doping of small amounts of Ir and Sb. It is notable that the water splitting over the photocatalyst proceeded with response to visible light up to 660 nm. This response wavelength is the longest compared with previously reported single particulate visible-light-driven photocatalysts for water splitting. The apparent quantum yield at 420 nm of the optimized photocatalyst was 0.73%. This photocatalyst was active for solar water splitting and gave 0.33% solar-to-hydrogen energy conversion efficiency (STH). Notably, water splitting proceeded giving 0.035% STH under visible light (λ > 440 nm) in a solar spectrum. Additionally, Rh, Ru, and Cr-doped SrTiO3 photocatalysts were also successfully developed for highly efficient water splitting under visible light irradiation by application of the strategies of small amounts of doping, flux treatment with SrCl2 with Al2O3 addition, and loading of a RhCrOx cocatalyst.

Chocron, Léa; Baggi, Nicolò; Ribeiro, Enrique; Goetz, Vincent; Yu, Pei; Nakatani, Keitaro; Métivier, Rémi

doi: 10.1039/d4sc04973jpmid: 39345771

Photochromic compounds are promising for a variety of applications, including molecular solar thermal (MOST) energy storage. The energy release step and cyclability are critical issues to be addressed for the development of this technology. We report herein the synthesis and characterization of two diarylethene molecules featuring one (1) or two (2) pyridine groups as protonatable moieties. Upon UV irradiation, both molecules undergo a cyclization reaction from the open form (OF) to the closed form (CF). Both CF are stable for a few days in acetonitrile, and the addition of acid leads to a 600 (1) or 1500-fold (2) acceleration of the ring-opening reaction, even in catalytic amounts. A kinetic model is proposed to simulate the reaction, elucidating the contribution of each step to the kinetics and evidencing the importance of the kinetic control over the protonation thermodynamic equilibrium. Data fitting leads to the rates of elementary steps and turnover numbers (TON). Following a complete reaction cycle, neutralization of the acid by an equivalent amount of base allowed further cycles. This study represents a significant advancement in the cyclability and the control of the on-demand triggering of the energy-releasing ring-opening reaction of diarylethenes for future MOST applications.