Recent Advances in Visible Light‐induced Asymmetric Transformations of Carbonyl Compounds into Chiral Alcohols

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Recent Advances in Visible Light-induced Asymmetric Transformations of Carbonyl Compounds into Chiral Alcohols

This review provides the overview of the fundamental concepts on ketone properties, and summarizes the recent advances of visible light-induced asymmetric reactions of carbonyl compounds for synthesizing chiral alcohols, which are introduced by the type of catalytic system, including single catalyst and synergetic catalysts. It is hopeful to provide guidance and assistance for the development of this field in future.


Abstract

Visible light-induced photocatalysis has been widely investigated, which offers exciting opportunities to build new catalytic platforms that are unattainable under ground state conditions. Asymmetric photocatalysis has been a longstanding challenge due to the high reactivity of photogenerated intermediates leading to strong background reaction. Carbonyl group is an important fundamental scaffold in organic synthesis. The photocatalytic asymmetric transformations of carbonyl compounds for synthesizing enantioenriched secondary and tertiary alcohols are of significant value but remain problematic. Even so, a series of intriguing works concerning this topic have been reported in recent year. This review summarizes the advances in this area, mainly dividing into single and synergetic catalyst systems, and the mechanism of each reaction is discussed.

Chemo‐Enzymatic Fluorescence Labeling Of Genomic DNA For Simultaneous Detection Of Global 5‐Methylcytosine And 5‐Hydroxymethylcytosine

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Chemo-Enzymatic Fluorescence Labeling Of Genomic DNA For Simultaneous Detection Of Global 5-Methylcytosine And 5-Hydroxymethylcytosine**

Dual-color global labelling of 5-hydroxymethylcytosine and umCpG by multi-color fluorescent labelling. We apply an engineered methyltransferase enzyme specific for unmodified CpG to incorporate a modified cofactor that binds to a fluorophore by click chemistry. In combination with 5-hydroxymethylcytosine labelling via enzymatic glycosylation, we incorporate spectrally distinct colour for each epigenetic mark, enabling simultaneous quantification in different cancer types.


Abstract

5-Methylcytosine and 5-hydroxymethylcytosine are epigenetic modifications involved in gene regulation and cancer. We present a new, simple, and high-throughput platform for multi-color epigenetic analysis. The novelty of our approach is the ability to multiplex methylation and de-methylation signals in the same assay. We utilize an engineered methyltransferase enzyme that recognizes and labels all unmodified CpG sites with a fluorescent cofactor. In combination with the already established labeling of the de-methylation mark 5-hydroxymethylcytosine via enzymatic glycosylation, we obtained a robust platform for simultaneous epigenetic analysis of these marks. We assessed the global epigenetic levels in multiple samples of colorectal cancer and observed a 3.5-fold reduction in 5hmC levels but no change in DNA methylation levels between sick and healthy individuals. We also measured epigenetic modifications in chronic lymphocytic leukemia and observed a decrease in both modification levels (5-hydroxymethylcytosine: whole blood 30 %; peripheral blood mononuclear cells (PBMCs) 40 %. 5-methylcytosine: whole blood 53 %; PBMCs 48 %). Our findings propose using a simple blood test as a viable method for analysis, simplifying sample handling in diagnostics. Importantly, our results highlight the assay‘s potential for epigenetic evaluation of clinical samples, benefiting research and patient management.

Recycling Graphite from Spent Lithium Batteries for Efficient Solar‐Driven Interfacial Evaporation to Obtain Clean Water

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Recycling Graphite from Spent Lithium Batteries for Efficient Solar-Driven Interfacial Evaporation to Obtain Clean Water

For clean water: Based on graphite from spent lithium-ion batteries, the reconstructed graphite porous hydrogel (RG-PH) was successfully prepared by crosslinking foaming technology, which showed a high evaporation rate for desalination under one sunlight irradiation, and effectively removed various organic contaminants in wastewater, including typical volatile organic compound of phenol.


Abstract

Solar-driven interfacial evaporation technology is regarded as an attracting sustainable strategy for obtaining portable water from seawater and wastewater, and the recycle of waste materials to fabricate efficient photothermal materials as evaporator to efficiently utilize solar energy is very critical, but still difficult. To this purpose, graphite recovered from spent lithium-ion batteries (SLIBs) was realized using a simple acid leaching method, and a reconstructed graphite-based porous hydrogel (RG-PH) was subsequently fabricated by crosslinking foaming method. The incorporation of reconstructed graphite (RG) improves the mechanical characteristics of hydrogels and the light absorption performance significantly. The evaporation rate of optimized RG-PH can constantly reach 3.4278 kg m−2 h−1 for desalination under a one solar irradiation, and it also showed the excellent salt resistance in various salty water. Moreover, RG-PH has a strong elimination of a variety of organic contaminants in wastewater, including the typical volatile organic compound of phenol. This research shows the potential application of flexible and durable solar evaporators made from waste materials in purifying seawater and wastewater, not only contributing to carbon neutrality by recycling graphite from SLIBs, but also ensuring the cost-effectiveness harvest of solar energy for constantly obtaining clean water.

Facile Formation of Sulfurized Nanorod‐Like ZnO/Zn(OH)2 and Hierarchical Flower‐Like γ‐Zn(OH)2/ϵ‐Zn(OH)2 from a Green Synthesis and Application as Luminescent Solar Concentrator

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Facile Formation of Sulfurized Nanorod-Like ZnO/Zn(OH)2 and Hierarchical Flower-Like γ-Zn(OH)2/ϵ-Zn(OH)2 from a Green Synthesis and Application as Luminescent Solar Concentrator

Green synthesis of sulfurized nanorod (NR)-like ZnO/Zn(OH)2 and hierarchical flower-like γ-Zn(OH)2/ϵ-Zn(OH)2 is reported for luminescent solar concentrators (LSC)-photovoltaic (PV) system. This combination shows a superior solar PV performance over the non-sulfurized analogues.


Abstract

This research endeavors to overcome the significant challenge of developing materials that simultaneously possess photostability and photosensitivity to UV-visible irradiation. Sulfurized nanorod (NR)-like ZnO/Zn(OH)2 and hierarchical flower-like γ-Zn(OH)2/ϵ-Zn(OH)2 were identified from XRD diffraction patterns and Raman vibrational modes. The sulfurized material, observed by FEG-SEM and TEM, showed diameters ranging from 10 and 40 nm and lengths exceeding 200 nm. The S2− ions intercalated Zn2+, modulating NRs to dumbbell-like microrods. SAED and HRTEM illustrated the atomic structure in (101) crystal plane. Its direct band gap of 3.0 eV was attributed to the oxygen vacancies, which also contribute to the deep-level emissions at 422 and 485 nm. BET indicated specific surface area of 4.4 m2 g−1 and pore size as mesoporosity, which are higher compared to the non-sulfurized analogue. These findings were consistent with the observed photocurrent, photostability and photoluminescence (PL), further supporting the suitability of sulfurized NR-like ZnO/Zn(OH)2 as a promising candidate for Luminescent solar concentrators (LSC)-photovoltaic (PV) system.

Laser‐Assisted Interfacial Engineering for High‐Performance All‐Solid‐State Batteries

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Laser-Assisted Interfacial Engineering for High-Performance All-Solid-State Batteries

Laser-assisted interfacial engineering for improving the stability of all-solid-state batteries: The recent achievements of ultrafast pulsed laser ablation, selective laser sintering, laser-induced interlayers, and pulsed laser deposition technologies resulting in stable interfaces in SSB full cells have been reviewed. This review outlines underlying photophysical and electrochemical mechanisms for the enhanced stabilities of laser-processed SSB full cells. It provides insights into future research on the laser-assisted manufacturing of high-performance SSBs.


Abstract

Safe and high-energy-density solid-state batteries (SSBs) are promising candidates for use as the primary power source of next-generation electric vehicles. However, their poor rate capabilities and long-term cyclabilities because of material and interfacial instabilities have hindered their widespread commercialization. This study reviewed the recent progress of laser-assisted interfacial engineering technologies to address the stability issues at the interfaces of SSBs. First, the overview of the interfacial issues of SSBs is briefly outlined. Subsequently, the recent achievements are summarized according to the photophysical mechanisms of laser processing and the type of interfaces to which they are applied. Consequently, the critical laser processing factors to improve the interfacial stabilities of SSBs are highlighted in detail. Finally, the future challenges and opportunities in laser-assisted interfacial engineering for manufacturing high-performance SSBs have been discussed to provide guidelines for developing reliable and scalable processes.

From Lignins to Renewable Aromatic Vitrimers based on Vinylogous Urethane

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From Lignins to Renewable Aromatic Vitrimers based on Vinylogous Urethane

Sustainable covalent adaptable networks (CANs): Vinylogous urethane CANs were developed according to green chemistry principles, from organosolv lignin using solvent-free reactions and non-toxics compounds. Structure-property relationship as well as the vitrimer behavior of the cross-linked materials was fully investigated. The recyclable materials also exhibited healing ability, improving their lifecycle and sustainability.


Abstract

During the two last decades, covalent adaptable networks (CANs) have proven to be an important new class of polymer materials combining the main advantages of thermoplastics and thermosets. For instance, materials can undergo reprocessing cycles by incorporating dynamic covalent bonds within a cross-linked network. Due to their versatility, renewable resources can be easily integrated into these innovative systems to develop sustainable materials, which can be related to the context of the recent development of a circular bioeconomy. Lignins, the main renewable sources of aromatic structures, are major candidates in the design of novel and biobased stimuli-responsive materials such as vitrimers due to their high functionality and specific chemical architectures. In the aim of developing recyclable lignin-based vinylogous urethane (VU) networks, an innovative strategy was elaborated in which lignin was first modified into liquid polyols and then into polyacetoacetates. Resulting macromonomers were integrated into aromatic VU networks and fully characterized through thermal, mechanical, and rheological experiments. Viscoelastic behaviors of the different aromatic vitrimers exhibited fast stress-relaxations (e. g., 39 s at 130 °C) allowing easy and fast mechanical reprocessing. A thermomechanical recycling study was successfully performed. Then, the developed strategy enabled the fabrication of healable biobased aromatic vitrimers with tunable structures and properties.

Lattice‐strained Metallic Aerogels as Efficient and Anti‐poisoning Electrocatalysts for Oxygen Reduction Reaction

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Lattice strain engineering optimizes the interaction between the catalytic surface and adsorbed molecules by adjusting the electron and geometric structure of the metal site to achieve high electrochemical performance, but it has been rarely reported on anti-poisoned oxygen reduction reaction (ORR) to date. Herein, lattice-strained Pd@PdBiCo quasi core-shell metallic aerogels (MAs) were designed by “one-pot and two-step” method for anti-poisoned ORR. Pd@PdBiCo MAs/C would maintain their original activity (1.034 A mgPd-1) in electrolytes with CH3OH and CO at 0.85 V vs. reversible hydrogen electrode (RHE), outperforming the commercial Pd/C (0.156 A mgPd-1), Pd MAs/C (0.351 A mgPd-1), and PdBiCo MAs/C (0.227 A mgPd-1). Moreover, Pd@PdBiCo MAs/C also show high stability and anti-poisoning with negligible activity decay after 8000 cycles in 0.1 M KOH + 0.3 M CH3OH. These results of X-ray photoelectron spectroscopy, CO stripping, and diffuses reflectance infrared Fourier transform spectroscopy reveal that the tensile strain and strong interaction between different elements of Pd@PdBiCo MAs/C effectively optimize electronic structure to promote O2 adsorption and activation, while suppressing CH3OH oxidation and CO adsorption, leading to high ORR activity and anti-poisoning property. This work inspires the rational design of MAs in fuel cells and beyond.

High Salt Electrolyte Solutions Challenge the Electrochemical CO2 Reduction Reaction to Formate at Indium and Tin Cathodes

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High Salt Electrolyte Solutions Challenge the Electrochemical CO2 Reduction Reaction to Formate at Indium and Tin Cathodes

Electrochemical feeding of salt-loving microorganisms: Halophilic microorganisms are promising for bioproduction from formate. Electrochemical CO2 reduction to formate necessitates high reaction kinetics, selectivity, and overall efficiency in saline conditions. Starting from a growth media for halophiles adjusting the concentration and composition of salts and buffers in electrolyte solutions enabled higher electrochemical production of formate.


Abstract

Formate is a promising product of the electrochemical CO2 reduction reaction (eCO2RR) that can serve as feedstock for biological syntheses. Indium (In) has been shown as a selective electrocatalyst of eCO2RR with high coulombic efficiency (CE) for formate production at small scale at biocompatible non-halophilic that is low salt conditions. Ohmic losses and challenges on potential/current distribution arise for scaling-up, where higher salt loads are advantageous for minimizing these. Higher salt concentration within the solution or halophilic conditions also enable the use of halophilic biocatalysts. We optimized eCO2RR with halophilic media by introducing tin (Sn) as a more sustainable alternative to In. At 3 % NaCl providing a catholyte conductivity ( of 70 mS cm−1, the maximum specific formate production rates (r formate) of 0.143±0.030 mmol cm−2 h−1 and 0.167±0.027 mmol cm−2 h−1 were achieved at In and Sn electrocatalysts, respectively. Decrease in r formate and CE, in addition to higher variation between replicates was observed with further increase in NaCl concentration above 3 % ( >70 mS cm−1) up to 10 % ( =127 mS cm−1). This study sets the foundation for integrated microbial synthesis by halophiles.

Food Waste Gasification to Produce Hydrogen for Proton Exchange Membrane Fuel Cell Applications: Comparison of Fixed‐Bed and Fluidized‐Bed Gasifiers Models

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Food Waste Gasification to Produce Hydrogen for Proton Exchange Membrane Fuel Cell Applications: Comparison of Fixed-Bed and Fluidized-Bed Gasifiers Models

The potential of biomass gasification, specifically food waste, as a solution for increasing energy demands and sustainable waste management is evaluated. The process of converting waste into syngas and subsequently purifying the hydrogen for use in proton exchange membrane fuel cells is described. The unique advantages and drawbacks of fixed and fluidized-bed gasifiers are highlighted.


Abstract

The proton exchange membrane fuel cell (PEMFC) has been expected to play a pivotal role in energy corridors within the next few years. The gasification of biomass sources is used to produce hydrogen. Many researchers have simulated the biomass gasification model through Aspen Plus to generate hydrogen. However, they have not been targeting the purification of hydrogen gas which is the product of biomass gasification. Thus, the Aspen gasification models for both the fixed and fluidized-bed gasifiers integrated with the hydrogen purification system to produce hydrogen for PEMFC applications are developed in this work. Food waste is selected as biomass feedstock. The gasifiers have been modeled on Gibbs free minimization energy. Shift reactors along with the preferential oxidation reactor have been employed to limit the amount of CO in the syngas. The validated models were then employed to estimate the performance of both the fixed-bed food waste gasifier and fluidized-bed food waste gasifier in terms of syngas produced and hydrogen obtained after purification.