Latest ArticlesBenzotriazole (BTA)-based A2-A1-D-A1-A2 type wide-bandgap (WBG) non-fullerene acceptors (NFAs) have shown promising potential in indoor photovoltaic, and in-depth investigation of their structure-property relationship is of great significance. Herein, we explored the chlorination effect of the side chain on the terminals. We introduced Cl atoms into the benzyl side chains in parent BTA5 to synthesize two NFAs, BTA5-Cl with mono-chlorinated benzyl groups and BTA5-2Cl containing bi-chlorinated benzyl groups. We chose D18-Cl with deep-energy levels and strong crystallinity to pair with these three acceptors, affording high photovoltage and photocurrent. With the stepwise chlorination, the open-circuit voltage (VOC) values decrease from 1.28, 1.22, to 1.20 V, while the corresponding power conversion efficiencies (PCEs) improve from 5.07%, 9.15%, to 10.96%. Compared with BTA5-based OSCs, introducing Cl atoms downshifts the energy levels and slightly increases the non-radiative energy loss (0.14 < 0.17 < 0.19 eV), resulting in a sequential decrease in VOC. However, more chlorine atom replacements produce more effective exciton dissociation, higher charge transfer, and balanced carrier mobility in the blend films, ultimately achieving better PCEs. This work indicates that chlorination of the benzyl group on the terminals can improve the device's performance, implying good application potential in indoor photovoltaics.
Photocatalytic technology harnesses solar energy to facilitate chemical transformations, presenting significant potential in energy generation and environmental remediation. However, the conventional O2 evolution process is hindered by high reaction barriers and inefficiencies, which limit its widespread application. Therefore, exploring novel photocatalytic coupling strategies to replace water oxidation has become a key route to enhance the efficiency of H2 production. In this review, organic pollutants removal and the valorization of organics as substitutes for water oxidation coupling strategies for photocatalytic H2 production are comprehensively summarized. These strategies not only circumvent the high reaction barriers associated with O2 evolution to enhance the H2 production but also aid in the removing of organic pollutants or synthesis of value-added chemicals. We also present future research directions and underscore the significance of advanced catalyst design, in-depth analysis of reaction mechanisms, and systematic optimization strategies in realizing an efficient and sustainable photocatalytic process. This guidance is anticipated to provide theoretical and practical new insights for the future development of photocatalytic coupling reactions, fostering further explorations in the realm of renewable energy and environmental governance.
The high conductivity of electrocatalyst can eliminate the Schottky energy barrier at the interface of heterogeneous phases during an electrocatalytic reaction and accelerate the rapid electron transfer to the catalytic active center. Therefore, the electronic conductivity is a vital parameter for oxygen reduction reaction (ORR). Covalent triazine frameworks (CTFs) have shown great potential application as electrocatalysts in ORR with a merit of the diverse building blocks. However, the intrinsic low conductivity and high impedance of CTFs could be significant setbacks in electrocatalytic application. Herein, CTFs were constructed by introducing F and N co-modification for efficient 2e− ORR. Compared with the pristine CTF, the co-presence of F, N could increase the conductivity obviously by 1000-fold. As a result, F-N-CTF exhibits enhanced catalytic performance of H2O2 generation and selectivity towards reaction pathways. This work reveals the importance of conductivity optimization for CTFs and provides guidance for designing high conductivity non-metallic organic semiconductor catalysts for 2e− ORR.
The synthesis of polyurethanes (PUs) from the reaction of low molecular weight poly(ethylene carbonate) diol (PECD) is rarely investigated. This work reports a novel PU with excellent mechanical properties from the solution polymerization of 4,4′-diphenylmethane diisocyanate (MDI) with PECD that was derived from the copolymerization of carbon dioxide (CO2) and ethylene oxide (EO). The tensile strength, the elongation at break and 300% constant tensile strength of the PECD-PU were up to 66 ± 2 MPa, 880% ± 50% and 13 MPa, respectively, higher than the control PUs from the reaction of MDI with commercial polyethers or polyesters. The PECD-PU with high CO2 carbonate content exhibited good solvent resistance and chemical stability. Of importance, the mechanical properties and chemical resistance of PECD-PU were significantly enhanced with the increasing content of CO2, i.e., the carbonate unit in PECD. This work provides comprehensive properties of PECD-derived PUs, indicating that PECD is a competitive precursor for the preparation of PU and has broad application prospects.
Atomically precise metal nanoclusters (NCs) have been deemed as a new generation of metal nanomaterials in the field of solar energy conversion due to their unique atomic stacking manner, quantum confinement effects, light-harvesting capability and multitude of active sites. Nonetheless, wide-spread application of monometallic NCs is blocked by the ultrashort carrier lifespan, uncontrollable charge transport pathway, and light-induced poor stability, impeding the construction of robust and stable metal NC-based photosystems. Herein, we report the fabrication of stable alloy (Au1-xPtx) NCs photosystem, for which tailor-made negatively charged l-glutathione (GSH)-capped Au1-xPtx NCs as the building blocks are controllably deposited on the BiVO4 (BVO) by a self-assembly approach for steering enhanced light absorption and interfacial charge transfer over alloy NCs-based photoanodes (Au1-xPtx/BVO). The self-assembled Au1-xPtx/BVO composite photoanode exhibits the significantly enhanced photoelectrochemical water oxidation performances compared with pristine BVO and Aux/BVO photoanodes, which is caused by the Pt atom doping into the Aux NCs for elevating photosensitivity and boosting the stability. The synergy of Au and Pt atoms in alloy NCs protects the gold core from rapid oxidation, improving the photostability and accelerating the surface charge transfer kinetics. Our work would significantly inspire ongoing interest in unlocking the charge transport characteristics of atomically precise alloy NCs for solar energy conversion.
Photocatalytic overall pure water splitting is a promising method for generating green hydrogen energy under mild conditions. However, this process is often hindered by sluggish electron-hole separation and transport. To address this, a step-scheme (S-scheme) B-doped N-deficient C3N4/O-doped C3N5 (BN-C3N4/O-C3N5) heterojunction with interfacial B-O bonds has been constructed. Utilizing Pt and Co(OH)2 as co-catalysts, BN-C3N4/O-C3N5 S-scheme heterojunction demonstrates significantly enhanced photocatalytic activity for overall pure water splitting under visible light, achieving H2 and O2 evolution rates of 40.12 and 19.62 µmol/h, respectively. Systematic characterizations and experiments revealed the performance-enhancing effects of the enhanced built-in electric field and the interfacial B-O bonding. Firstly, the strengthened built-in electric field provides sufficient force for rapid interfacial electron transport. Secondly, by reducing the transport energy barrier and transfer distance, the interfacial B-O bonds facilitate rapid recombination of electrons and holes with relatively low redox potential via the S-scheme charge-transfer route, leaving the high-potential electrons and holes available for H+ reduction and OH− oxidation reactions. Overall, the photocatalytic efficiency of BN-C3N4/O-C3N5 S-scheme heterojunction was significantly improved, making it a promising approach for green hydrogen production through overall pure water splitting.
Precise tumor targeting and therapy is a major trend in cancer treatment. Herein, we designed a tumor acidic microenvironment activatable drug loaded DNA nanostructure, in which, we made a clever use of the sequences of AS1411 and i-motif, which can partially hybridize, and designed a simple while robust DNA d-strand nanostructure, in which, i-motif sequence was designed to regulate the binding ability of the AS1411 aptamer to target tumor. In the normal physiological environment, i-motif inhibits the targeting ability of AS1411. In the acidic tumor microenvironment, i-motif forms a quadruplex conformation and dissociates from AS1411, restoring the targeting ability of AS1411. Only when acidic condition and tumor cell receptor are present, this nanostructure can be internalized by the tumor cells. Moreover, the structure change of this nanostructure can realize the release of loaded drug. This drug loaded A-I-Duplex DNA structure showed cancer cell and spheroid targeting and inhibition ability, which is promising in the clinical cancer therapy.
In this work, we developed plasmonic photocatalyst composed of CuPd alloy nanoparticles supported on TiN, the optimized Cu3Pd2/TiN catalyst shows excellent conversion (> 96%) and selectivity (> 99%) for Heck reaction at 50 ℃ under visible light irradiation. By in-situ spectroscopic investigations, we find that visible light excitation could achieve stable metallic Cu species on the surface of CuPd alloy nanoparticles, thereby eliminating the inevitable surface oxides of Cu based catalyst. The in-situ formed metallic Cu species under irradiation take advantage of the strong interactions of Cu with visible light, and manifest in the localized surface plasmon resonances (LSPR) photoexcitation. Visible light excitation could further promote the charge transfer between catalytic Pd component and the support TiN, resulting in electron-rich Pd sites on CuPd/TiN. Moreover, light excitation on CuPd/TiN generates strong chemisorption of iodobenzene and styrene, favoring the activation of reactants for Heck reaction. DFT calculations suggest that electron-rich CuPd sites ideally lower the activation energy barrier for the coupling reaction. This work provides valuable insights for mechanistic understanding of plasmonic photocatalysis.
In-situ enhanced bioreduction by functional materials is a cost-effective technology to remove chlorinated hydrocarbons in groundwater. Herein, a novel polydopamine (PDA)-modified biochar (BC)-based composite containing nanoscale zero-valent iron (nZVI) and poly-l-lactic acid (PLLA) (PB-PDA-Fe) was synthesized to enhance the removal of 1,1,1-trichloroethane (1,1,1-TCA) in simulated groundwater with actual site sediments. Its impact on functional microbial community structure in system was also investigated. The typical characterizations revealed uniform dispersion of PLA and nZVI particles on the BC surface, being smoother after PDA coating. The composite exhibited a significantly higher performance on 1,1,1-TCA removal (82.38%, initial concentration 100 mg/L) than Fe-PDA and PB-PDA treatments. The diversity and richness of the microbial community in the composite treatment consistently decreased during incubation due to a synergistic effect between PLLA-BC and nZVI. Desulfitobaterium, Pedobacter, Sphaerochaeta, Shewanella, and Clostridium were identified as enriched genera by the composite through DNA-stable isotope probing (DNA-SIP), playing a crucial role in the bioreductive dechlorination process. All the above results demonstrate that this novel composite selectively enhances the activity of microorganisms with extracellular respiration functions to efficiently dechlorinate 1,1,1-TCA. These findings could contribute to understanding the responsive microbial community by carbon-iron composites and expedite the application of in-situ enhanced bioreduction for effective remediation of chlorinated hydrocarbon-contaminated groundwater.
Disulfidptosis, a novel mechanism of programmed cell death through the disruption of tumor metabolic symbiosis (TMS), has showed tremendous potential in cancer therapy. However, the efficacy of disulfidptosis is limited by poor permeability of drugs in solid tumors. Herein, hydrogen sulfide (H2S) and near-infrared (NIR) light-driven nanomotors (denoted as HGPP) have been constructed to efficiently penetrate tumors and induce disulfidptosis. HGPP demonstrate glutathione (GSH)-responsive release of H2S, which combined with NIR light-induced photothermal effect drive HGPP movement to facilitate deep tumor penetration. The released H2S induces tumor acidosis and disrupts TMS, where disulfide accumulation following cell starvation leads to disulfidptosis. In addition, HGPP induce hepatoma specific cellular uptake and catalyze the conversion of glucose and oxygen to produce hydrogen peroxide (H2O2), leading to glucose starvation. Overall, this study has developed a multifunctional Janus nanomotor that provides a novel strategy for disulfidptosis-based solid tumor therapy.