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The development of peroxidase mimics with enhanced peroxidase-like activity is critical to building a convenient and fast glucose colorimetric sensor. Herein, a porphyrin-based conjugated microporous polymer (FePCMP) was synthesized through a Pd-/CuI catalyzed Sonogashira coupling reaction. The FePCMP exhibited specific and superior POD-like activity evaluated by the fast oxidation of 3,3′,5,5′-tetramethylbenzidine (a chromogenic substrate, TMB) to form the blue product (oxTMB) in the presence of H2O2. The outstanding POD-like activity is mainly ascribed to the Fe-N4 active sites and the cross-linked porous framework of FePCMP. Furthermore, the FePCMP was applied in selective colorimetric detection of glucose through a glucose oxidase biocatalytic cascade reaction with a low detection limit (LOD) of 0.031 [Formula: see text]M in the linear range of 0.2–5 [Formula: see text]M. This study not only provided a new method for the design and synesis of specific POD-like nanozymes, but also the prepared FePCMP can be used as a POD-like enzyme for the colorimetric detection of other molecules, such as cholesterol, acetylcholine, etc.

Singlet fission (SF), which can convert one singlet exciton into two triplet excitons, has the potential to enhance the solar energy conversion efficiency in devices such as photovoltaic cells and processes such as photocatalysis.

The Schottky junction of the coupled metallic Bi/Bi2O3 core–shell structure and g-C3N4 significantly improves the photocatalytic H2O2 evolution efficiency in pure water.

Herein, the "push effect" strategy combined with "triple-phase-boundary" (TPB) engineering was innovatively employed to target the single Fe-N

To evaluate the role of the charge transfer (CT) state in the singlet fission (SF) process, we prepared three 3,6-bis(thiophen-2-yl)diketopyrrolopyrrole (TDPP) derivatives with zero (Ph

To harvest two triplet excitons of singlet fission (SF) via a two-electron transfer efficiently, the revelation of the key factors that influence the two-electron-transfer process is necessary. Here, by using steady-state and transient absorption/fluorescence spectroscopy, we investigated the two-electron-transfer process from the two triplet excitons of intramolecular SF (iSF) in a series of tetracene oligomers (dimer, trimer, and tetramer) with 7,7,8,8-tetracyanoquinodimethane (TCNQ) as an electron acceptor in solution. Quantitative two-electron transfer could be conducted for the trimer and tetramer, and the rate for the tetramer is faster than that for the trimer. However, the maximum efficiency of the two-electron transfer in the dimer is relatively low (∼47%). The calculation result of the free energy change (Δ

An efficient SF material (ΦT = 164%) based on an anthracene dimer with high triplet energy (1.51 eV) and good stability simultaneously was achieved for the first time.

An outstanding oxygen reduction reaction (ORR) electrocatalyst is firstly developed deriving from sustainable rice husk (RH) biomass. Benefiting from self-doped Si in RH, the higher proportion of pyridine N, graphite N and expecially Fe-Nx as well as thiophene S contents were produced in Si-Fe/S/N-RH3 in comparison with those of Si-free Fe/S/N-RH3. Consequently, the half-wave potential of 0.89 V and the onset potential of 0.96 V are achieved for Si-Fe/S/N-RH3, outperforming the benchmark electrocatalyst Pt/C and other Fe-based electrocatalysts reported in alkaline media. Furthermore, it is found that the exisentence of self-doped Si can improve the graphitization degree of the catalyst, leading to the long-term stability (larger than 85% retention after 40000 s) and prominent methanol tolerance for Si-Fe/S/N-RH3. In addition, Si-Fe/S/N-RH3 shows a power density of 86.2 mW cm−2 and excellent durability in Zn-air battery. The work highlights the potential to develop sustainable and cost-effective ORR electrocatalysts from waste biomass as the substitute for precious metal catalysts.

Diketofurofuran derivatives show comparable singlet fission relevant excited state energies with diketopyrrolopyrrole analogues and tetracene.

Accelerated hole extraction efficiency through effective BSBF–NH2 molecule surface passivation.

Fast symmetry breaking charge separation (SB-CS) rate and slow CS recombination rate were achieved simultaneously via tuning the molecular geometry.

An efficient SF material with broadband light harvesting ability was prepared by means of ultrafast intramolecular Förster resonance energy transfer.

Ni/NiS-Modified twin Zn0.5Cd0.5S efficiently catalyzes CAL to HCOL products with >99% yield within 80 min under visible-light irradiation.

Reducing the loading of Pt precious metal is the promising pathway to positively promote the large-scale application for fuel cells and water electrolysis. In this work, a composite bifunctional electrocatalyst (named Pt@Fe

The hydrogen evolution reaction (HER) via water electrolysis has gained immense research attention. Seawater electrolysis provides great opportunities for sustainable energy production, but is extremely challenging. Transition metal phosphides are promising candidate electrocatalysts. Herein, we prepared a novel Fe–Co2P bundle of nanorods (BNRs) for catalyzing the HER in seawater electrolysis and over the entire pH range. Cobalt phosphides with different crystal phases and morphologies were obtained by varying the Fe doping amount. The Co:Fe molar ratio of 1:0.5 was found to be optimum. The Fe doping improved the HER performance of Co2P over the entire pH range by providing favorable electronic properties and morphology, lattice distortion, and special coordination environment. The Fe-Co2P BNRs showed higher catalytic activity than 20% Pt/C in seawater at high potentials. The density functional theory calculations revealed that the Fe doping reduced the hydrogen binding strength of Co2P to efficiently accelerate the HER kinetics and produce a favorable charge density. This study provides valuable insights into the design and development of high-efficiency HER catalysts for large-scale seawater electrolysis.

A robust 2,2'-bipyridine (bpy)-derived biological hydrogen-bonded framework (HOF-25) has been realized depending on guanine-quadruplex with the assistance of π-π interaction, which reacts with Re(CO)5 Cl to give a post-functionalized HOF-25-Re. X-ray absorption fine structure spectroscopic study on HOF-25-Re confirms the covalent attachment of Re(bpy)(CO)3 Cl segments to this HOF. Robust and recycled HOF-25-Re bearing photocatalytic Re(bpy)(CO)3 Cl centers displays good heterogeneous catalytic activity towards carbon dioxide photoreduction in the presence of [Ru(bpy)3 ]Cl2 and triisopropanolamine in CH3 CN under visible-light irradiation, with both high CO production rate of 1448 μmol g-1 h-1 and high selectivity of 93 %. Under the same conditions, the experimental turnover number of HOF-25-Re (50) is about 8 times as that of the homogeneous control Re(bpy)(CO)3 Cl. The sustainably regenerated HOF-25-Re via crystallization and post-modification processes shows recovered photocatalytic performance.

The energy level mismatching between SnO

Iron porphyrin microporous polymers with hierarchical porous structures and highly uniformly dispersed iron atoms anchored by nitrogen-containing ligands have great potential for the design and preparation of efficient non-noble metal oxygen reduction reaction (ORR) catalysts. Herein, a “micropores & active species protection” strategy is reported to construct a non-noble metal ORR catalyst by introducing polythiophene (PTh) into the porous structure of a tetraphenyl iron porphyrin microporous polymer (FeTPP-MP), followed by carbonization at 900 °C to obtain the Fe/S/N-composited porous carbon catalyst (FeTPP-MP@PTh-900) for the ORR. A comprehensive analysis of the structure and morphology of the resultant FeTPP-MP@PTh-900 reveals that the introduction of PTh not only increases the stability of the porous structure, but also prevents the agglomeration of iron active species during pyrolysis. Meanwhile, PTh as a S source ensures the doping of heteroatom S active sites into the resulting carbon matrix that optimizes the surface electron dispersion of N–S-doped FeTPP-MP@PTh-900 and decreases the work-function of the catalyst. As a result, FeTPP-MP@PTh-900 comprises abundant Fe2O3/Fe3C active species well-dispersed on the N–S-doped carbon matrix, displaying a more positive half-wave potential of 0.89 V than Pt/C (0.84 V) in alkaline electrolyte, and a small Tafel slope of 61 mV dec−1. It also shows outstanding ORR activity and durability in an acidic medium. Finally, FeTPP-MP@PTh-900 can be used as an air cathode for zinc–air batteries, which showed outstanding durability and a superior peak power density of 106 mW cm−2. The present work offers new prospects for the design of efficient, NPM-based materials for zinc–air batteries.

Effective and selective removal of radioactive metal ions from aqueous solutions is of great importance due to their harmful effects on humans and other living species. However, it is a big challenge for researchers to develop effective adsorbents with high selectivity and a wide pH application range even if some progress has been achieved. Herein, we report an anionic potassium organic framework (UPC-K1) with protonated dimethylamine (Me2NH2+) residing inside the rhomboid channels. The unique 3D firm structure of UPC-K1 is constructed by the cross-linking of the 2D arrangement using weak K-O bonds (2.9270 Å) and strong hydrogen bonds (1.6498 Å), which endows it with excellent chemical stability in organic solvents, boiling water, and aqueous solution in the pH range 3-10. Based on the cation exchange, depending on pore size selectivity, UPC-K1 shows excellent adsorption performance towards UO22+ in aqueous solutions at 298 K with the following characteristics: (1) effective removal in the pH range 3-10; (2) high selectivity over other metal cations; (3) a high adsorption capacity of 551.4 mg g-1; (4) a rapid adsorption equilibrium within 3 hours under stirring; and (5) effective adsorption at low concentrations, with a residual concentration of 0.69 ppm even at an initial concentration of 10.3 ppm after stirring for 24 hours. These results indicate the great potential of UPC-K1 in the treatment of uranium-containing nuclear wastewater.

Cathodic photoelectrochemical (PEC) biosensors are one of ideal systems for sensing applications owing to their advantages in the low-cost, simplicity of the detection and miniaturization of the sensors with high sensitivity and specificity. Herein, a high-performance PEC sensor based on a 2D porphyrin–phthalocyanine conjugated microporous polymer (PorPc-CMP) is reported for the specific detection of H2O2 and glucose in the wide linear ranges of 0.05–100 and 0.05–5000 μM with an ultra-low limit of detection (LOD) of 13 and 27 nM, respectively. All of them achieved the best levels, when compared to H2O2 and glucose tetrapyrrole-based photoelectrochemical sensors reported so far. After a comparative analysis on the morphology, optical–electrical properties and partial charge density plots by DFT calculations for the PorPc-CMP and its analogues (PorPor-CMP and PcPc-CMP), it is revealed that the high PEC-sensing performance of PorPc-CMP is largely related to the synergistic effect of unique multi-channel D–A structure and elaborate hollow tube-like morphology, which leads to the effective charge separation, enhanced charge transportability and high utilization of light irradiation. Furthermore, good accuracy of the PorPc-CMP PEC sensor was demonstrated in real sample analysis of H2O2 disinfectant and human serum samples.

Facilitating charge separation as well as surface redox reactions is considered to be an efficient way to improve semiconductor-based photocatalytic hydrogen generation. In this study, we developed a highly active and reliable photocatalyst, ReS2/T-ZCS, by anchoring nanoflower-like ReS2 particles on the surface of host chalcogenide nanotwins (Zn0.5Cd0.5S). By virtue of the in-built driving force from the homojunction with a type-II staggered band alignment in twin crystal Zn0.5Cd0.5S (T-ZCS) and heterojunctions between T-ZCS and ReS2 on the surface of the photocatalyst, a substantially improved charge separation and transfer property were achieved. Hence, the twin crystal Zn0.5Cd0.5S decorated nanoflower-like ReS2 exhibits a significantly improved photocatalytic H2 evolution rate of 112.10 mmol g−1 h−1 and the corresponding apparent quantum efficiency reaches 32.65% at 420 nm, which is 31 times larger than that of pure phase Zn0.5Cd0.5S. Our work not only couples the merits of homojunctions and heterojunctions to promote solar energy conversion, but also expands applications of the transition metal dichalcogenide (TMD) family in electrocatalysis, photothermal-catalysis and energy storage.

High-quality and uniform perovskite films are the first step toward high-performance perovskite solar cells (PSCs). Adding additives to regulating the film formation process is proved to be an effi...

Activatable triplet photosensitization refers to a photosentization process which can be turned on/off easily by external stimulus. Activatable triplet photosensitizations are normally achieved by interfering with the singlet excited state before the intersystem cross process (ISC), i.e., the formation process of triplet states of sensitizer. To achieve novel activatable triplet photosensitization, a disulfide-bridged porphyrin zinc(II) dyad (ZnPor-S-S-ZnPor) is prepared. Although fast ISC can be conducted in this dyad, an extremely low efficiency is obtained when employing this dyad as a triplet donor in triplet-triplet annihilation upconversion (TTA-UC) for sensitizing perylene. This is because of the presence of electron transfer from the triplet state of the porphyrin zinc(II) unit to the disulfide bond, which quickly quenches the triplet state of the porphyrin zinc(II) unit. This electron transfer process can be stopped by the cleavage of the disulfide bond in the presence of thiol, and TTA-UC efficiency can be enhanced significantly. Our result demonstrates for the first time that the disulfide bond can act as not only an easy cleavage linker but also a triplet electron acceptor. Furthermore, quenching the triplet states of sensitizer by triplet electron transfer provides an alternative protocol for designing activatable triplet sensitizers except controlling the singlet excited state before the ISC process.

In this paper, we report a novel self-supported PANI@MnO2 coaxial nanowire network sponge as a binder free electrode for supercapacitors. The as-prepared material has long MnO2 nanowire core, uniform PANI shell, intertwined nanowire networks and sponge-like structure. Its unique structure promotes the conductivity, electrochemical performance and stability of the material. The specific capacitance of this PANI@MnO2 coaxial nanowire network sponge electrode was as high as 344 F·g−1 and maintained about 98.6% of its initial value. Moreover, a high energy density of 86 Wh·kg−1 at a power density of 400 W·kg−1 was obtained tested by a symmetric capacitor. This remarkable electrochemical performance indicated its superior application potential in supercapacitors.

Facile preparation of cost-effective and durable porous carbon-supported non-precious-metal/nitrogen electrocatalysts for oxygen reduction reaction (ORR) is extremely important for promoting the commercialized applications of such catalysts. In this work, the FeCl3-containing porphyrinato iron-based covalent porous polymer (FeCl3·FePor-CPP) was fabricated in-situ onto porous corncob biomass supports via a simple one-pot method. Subsequent thermal-reduction pyrolysis at 700 °C–900 °C with CO2 gas as an activating agent resulted in Fe2O3-decorated and N-doped graphitic carbon composite Fe2O3@NCb NC = N-doped graphene analog; bio-C = the corncob-derived hierarchically porous graphitic biomass carbon framework). The derived α-Fe2O3 and γ-Fe2O3 nanocrystals (5–10 nm particle diameter) were all immobilized on the N-doped bio-C micro/nanofibers. Notably, the Fe2O3@NC&bio-C obtained at the pyrolysis temperature of 800 °C (Fe2O3@NC&bio-C-800), exhibited unusual ORR catalytic efficiency via a 4-electron pathway with the onset and half-wave potentials of 0.96 V and 0.85 V vs. RHE, respectively. In addition, Fe2O3@NC&bio-C-800 also exhibited a high and stable limiting current density of -6.0 mA cm−2, remarkably stability (larger than 91% retention after 10000s), and good methanol tolerance. The present work represents one of the best results for iron-based biomass material ORR catalysts reported to date. The high ORR activity is attributed to the uniformly distributed α-Fe2O3 and γ-Fe2O3 nanoparticles on the N-enriched carbon matrix with a large specific surface area of 772.6 m2 g−1. This facilitates favor faster electron movement and better adsorption of oxygen molecules on the surface of the catalyst. Nevertheless, comparative studies on the structure and ORR catalytic activity of Fe2O3@NC&bio-C-800 with Fe2O3@bio-C-800 and NC&bio-C-800 clearly highlight the synergistic effect of the coexisting Fe2O3 nanocrystals, NC, and bio-C on the ORR performance.

Although light-responsive nanozyme have been widely used in colorimetric sensing, some limitations such as poor catalytic activity, low detection efficiency, and unclear structure-activity relationships remain unresolved. Herein, we prepared an excellent light-responsive peroxidase (POD) mimic, perylenediimide (PDI-OH) modified SiO