Slow Charge Transfer Research Articles

In-situ growth of FeCo layered double hydroxide nanorods on MXene for high-performance supercapacitor electrodes

In the pursuit of clean energy solutions, supercapacitors have gained attention due to their exceptional energy storage capabilities. Layered double hydroxide (LDH), a notable material in this field, faces some challenges such as slow charge transfer speed and volumetric expansion. To tackle these issues, a novel FeCo-LDH/MXene composite was synthesized through in-situ hydrothermal growth of FeCo layered double hydroxide (FeCo-LDH) nanorods on MXene using ionic self-assembly, forming a three-dimensional (3D) composite with enhanced rate capability and cycling stability due to the synergetic coupling of MXene and LDH. The FeCo-LDH/MXene electrode significantly improves surface capacitance control performance and exhibits exceptional electrochemical performance, achieving a specific capacitance of 2058.2 F g−1 at 1 A g−1 and maintaining 1732.7 F g−1 at 10 A g−1, with 82.4 % capacity retention. Furthermore, the assembled supercapacitor delivers an energy density of 48.8 Wh kg−1 at 750 W kg−1 and 25.7 Wh kg−1 at 15000 W kg−1, demonstrating excellent rate performance, as well as 80.3 % capacitance after 5000 cycles at 2 A g−1, highlighting its durability. This advancement not only overcomes the specific capacitance challenge of MXene electrodes but also enhances the conductivity and cyclic stability of LDH, making FeCo-LDH/MXene a promising candidate for future high-performance energy storage applications.

Enhanced X-ray shielding efficiency and visible light degradation performance of a multilayer composite protective material

To mitigate the adverse effects of high-energy radiation, such as X-rays, on patients during medical procedures, a multifunctional composite nanofibrous membrane has been engineered to shield against low-energy X-rays. This study involves integrating processed oil-tea camellia shells (OCS) powder into molten polylactic acid (PLA) for modification. Concurrently, metallic Bi is introduced to enhance Bi2WO6, which is subsequently combined with modified PLA and electrospun into nanofibrous membranes for photocatalytic antimicrobial and organic pollutant degradation. Additionally, sodium hyaluronate (NaHA) and a silver nanoparticle solution are electrospun with PLA to form a skin-friendly protective layer. Following this, a chitosan (CS) solution containing WO3 and B4C is used as a coating on the multilayered membranes. The membranes are then freeze-dried to create sandwich-structured multilayer composite protective material. This method addresses challenges associated with polylactic acid (PLA) in electrospinning and alleviates limitations such as low light absorption and slow charge transfer in Bi2WO6. Compared to similar materials, this composite material is lightweight, flexible for cutting, and exhibits strong X-ray shielding capabilities. The composite nanofibrous membrane demonstrates a shielding efficiency of 97.75 ± 2.05 % at low X-ray energy (46 kVp). Moreover, under visible light, the membrane generates reactive oxygen species, resulting in the efficient removal of 98.03 % of methylene blue (MB), 96.35 % of rhodamine B (Rh.B), and 91.51 % of methyl orange (MO) within 180 minutes. Furthermore, it displays bactericidal activity against E. coli and S. aureus under both dark and light conditions. In natural settings, the composite membrane undergoes gradual degradation in soil, completely decomposing within 28 days due to the influence of rainfall and microorganisms. Consequently, this composite membrane holds significant promise for specialized medical protective applications.

Nickel-doped and surface fluorinated tungsten trioxide photoanode with enhanced photoelectrochemical water oxidation

To improve the slow charge transfer and high electron-hole recombination rate of tungsten trioxide (WO3), a nickel-doped and surface fluorinated WO3 photoanode is proposed. Compared with the unmodified and one-step modified WO3 photoanodes, the co-modified F/Ni-WO3 with two steps exhibits superior photoelectrochemical (PEC) performance with a significantly high photocurrent density of 1.03 mA/cm2 compared to 0.51 mA/cm2 of bare WO3 at 1.23 V vs. RHE. Ni doping can accelerate the kinetics of water oxidation and extend the light absorption range of the WO3 photoanode, while surface fluorination can enhance the surface electronegativity and hydrophilicity of the WO3 photoanode. The synergistic influence of the Ni doping and surface fluorination results in a lower carrier transport impedance, higher charge separation efficiency and larger electrochemically active surface of the WO3 photoanode which eventually contribute to the enhanced PEC performance for water oxidation.

In Situ Construction of Bimetallic Selenides Heterogeneous Interface on Oxidation-Stable Ti3C2Tx MXene Toward Lithium Storage with Ultrafast Charge Transfer Kinetics.

Ti3C2Tx (MXene) is widely acknowledged as an excellent substrate for constructing heterogeneous structures with transition metal chalcogenides (TMCs) for boosting the electrochemical performance of lithium-ion storage. However, conventional synthesis strategies inevitably lead to poor electrochemical charge transfer due to Ti3C2Tx-derived TiO2 at the heterogeneous interface between Ti3C2Tx and TMCs. Here, an innovative in situ selenization strategy is proposed to replace the originally generated TiO2 on Ti3C2Tx with metallic TiSe2 interphase, clearing the bottleneck of slow charge transfer barrier caused by MXene oxidation. The construction of bimetallic selenide formed by CoSe2 and TiSe2 generates intrinsic electric fields to guide the fast ion diffusion kinetics in a heterogeneous interface. Additionally, the CoSe2/TiSe2/Ti3C2Tx heterogeneous structure with enhanced structural stability and improved rate performance is confirmed by both experiments and theoretical calculations. The engineered heterogeneous structure exhibits an ultra-high pseudocapacitance contribution (73.1% at 0.1mVs-1), rendering it well-suited to offset the kinetics differences between double-layer materials. The assembled lithium-ion capacitor based on CoSe2/TiSe2/Ti3C2Tx possesses a high energy density and an ultralong life span (89.5% after 10000 times at 2Ag-1). This devised strategy provides a feasible solution for utilizing the performance advantages of MXene substrates in lithium storage with ultrafast charge transfer kinetics.

Physical reservoir computing with visible-light signals using dye-sensitized solar cells

Physical reservoir computing (PRC) with visible-light signals was demonstrated using dye-sensitized solar cells. The short-term memory required for PRC was confirmed using light pulse inputs. Waveform learning was demonstrated for nonlinear autoregressive moving-average time series level 2 (NARMA2) signals with normalized mean square error of 0.027. The relatively slow (milliseconds to seconds) and complex charge transfer dynamics in the TiO2 porous layer with redox reactions in the solution phase provided the characteristics required for PRC.

Optimizing sodium storage mechanisms and electrochemical performance of high Nitrogen-Doped hard carbon anode materials Derived from waste plastics for Sodium-Ion batteries

The development of high-performance hard-carbon (HC) anode materials for sodium-ion batteries was constrained by slow charge-transfer kinetics and sodium-storage mechanisms. In this paper, high nitrogen-doped (12.24 %) HC with an efficient interworking structure was synthesized in situ using waste plastics as precursors by utilizing the strong 2-D self-template effect of guanine. Elucidating the mechanism of sodium storage in heteroatom-doped carbon with coexisting heterocyclic and graphitic nitrogen, which synergistically enhances electrochemical activity, utilizing a range of in-situ and ex-situ characterization methods. Based on density functional theory (DFT), it has been discovered that the doping of pyrrole nitrogen (N5) and pyridinium nitrogen (N6) can effectively expand the interlayer spacing during the Na+ sodiated/de-sodiated process, thereby enhancing electrochemical activity. The optimized HC has increased the Na+ diffusion coefficient by 1.5 orders of magnitude (10-8.2 cm2 s−1 vs 10-9.76 cm2 s−1) and exhibits high reversible capacity (452 mAh/g@20 mA g−1), high rate performance (388mAh/g@500 mA g−1), superior cycling stability (87.6 % @500 mA g−1 after 2,000 cycles). The full cell exhibits good cyclic stability (91.87 %@100 mA g−1 after 2,00 cycles), while the designed pouch cell also demonstrates favorable cycle life (90.78 %@200 mA g−1 after 100 cycles).

(Invited) Role of the Energy Offset in the Charge Separation at the Donor: Acceptor Interface

The trade-off between the short-circuit current density and open-circuit voltage has been one of the largest bottlenecks for further improving the device performance of organic solar cells (OSCs). Therefore, understanding the limit to which the energy offset can be reduced and the physics underlying the trade-off relationship is crucial. This study provides a threshold energy that can ensure high charge photogeneration efficiencies for Y-series nonfullerene acceptor-based OSCs and discusses the role of the energy offset in charge separation. In this study, we used transient absorption spectroscopy to track the time evolution of electroabsorption caused by electron-hole pairs generated at donor:acceptor interfaces. We found that an insufficient energy offset led to not only slow charge transfer at the donor:acceptor interfaces, but also inefficient long-range spatial dissociation of the charge transfer states. Our findings highlight the importance of overcoming the trade-off between fill factor and open-circuit voltage for further improving the power conversion efficiency.

Nanoparticulated Vanadium Oxide on BiVO4 for Boosting Photoelectrochemical Glycerol Oxidation

Hydrogen (H2) has been spotlighted as ideal energy carrier due to its relatively higher energy density compared to fossil fuel and no carbon emissions during the energy generation. However, most of current produced H2 comes from as byproducts in fossil fuel reforming processes. To reduce dependence on fossil fuel in the H2 production process, photoelectrochemical (PEC) water splitting is considered as promising strategy for producing H2 using sustainable resources. Nevertheless, the insufficient efficiency in PEC water oxidation oxygen evolution reaction (OER) has limited overall PEC water splitting system efficiency due to its relatively high oxidation potential and sluggish catalytic kinetics. Furthermore, the low value of generated oxygen has been pointed out as obstacle from an economic perspective. To overcome these challenges, glycerol, byproduct of biodiesel, has been attracted numerous attentions as PEC oxidation resource since it has three hydroxyl groups and relatively lower oxidation potential than OER. Furthermore, glycerol oxygenated value-added products like dihydroxyacetone (DHA) can improve economics of PEC hydrogen production system. Upon these strengths, PEC glycerol oxidation reaction (GOR) provides improved strategy that generates value-added products in anodic part and green energy source (H2) in cathodic part simultaneously, which can replace PEC water splitting. Bismuth vanadate (BiVO4) is one of the most promising transition metal oxide based catalyst for PEC GOR due to its relatively narrow bandgap, high theoretical photocurrent density and deep positive valence band maximum (VBM) position. Additionally, although the surface kinetics of BiVO4 for OER has been sluggish, it potentially would be advantage for GOR with high production rate. However, the relatively instability of BiVO4 in acidic electrolyte during operation and lower selectivity of oxygenated products has hindered their practical application in PEC GOR. To solve these problems, introduction of nanoparticles as cocatalysts has been much studied for ameliorating surface kinetics and passivation the surface of photoanode. However, the interface between nanoparticles and photoanode with poor chemical interaction can induce the higher interfacial resistance and slow charge transfer efficiency rather. In this study, we present in-situ vanadium oxide (VOx) nanoparticle decoration on the surface of BiVO4 (VOx/BiVO4) via selective etching process using alkaline treatment for enhancing PEC GOR and we report the world best photocurrent density based on BiVO4 photoanode for GOR with high selective DHA production. VOx nanoparticles with an average size of 5 nm by selective etching process using alkaline treatment is decorated on the surface of BiVO4. The VOx promotes the surface reaction kinetics via modulating the fermi level and enhanced photovoltage of BiVO4 and improves long-term stability for GOR by compensation of V5+ and Bi3+, which combines both efficiency and stability. Furthermore, the surface decorated photoanode presents a 6.82 mA/cm2 (1.34-fold improvement) photocurrent density at 1.23 V versus the reversible hydrogen electrode (RHE) under 1 sun illumination, which has been attributed enhanced catalytic kinetics with upshifted fermi level and photovoltage of BiVO4. Moreover, the long-term stability of VOx/BiVO4 has been exhibited over 10 hours and the high selectivity for DHA is achieved. This study presents insight into the role vanadium of selective etched VOx on the surface of BiVO4 with low valence state than that of BiVO4 and improving the potential of BiVO4 based catalyst as GOR photoanode for high selective value-added DHA production using solar energy.

Interplanar spacing and nanosheet thickness regulation of carbon nitride and its “cold” catalytic hydrogen production performance under 10 W LED irradiation

Investigation of hydrogen production catalysis under low-temperature and low-power light irradiation, such as LEDs, is important for energy conservation in cold natural conditions. Interlayer charge transfer in g-C3N4 nanosheets is influenced by the crystal face spacing and nanosheet thickness, due to rapid photogenerated carrier recombination and slow charge transfer, thus enhancing hydrogen production capabilities. Few studies have controlled both crystal face spacing and nanosheet thickness simultaneously. In this research, copper-phosphorus co-doped g-C3N4 was synthesized through one-step thermal polymerization, achieving both control over nanosheet thickness and crystal surface spacing. The hydrogen production rate of 0.5 %Cu/1 %P doped g-C3N4 was increased by 5.25 times and reached 958.98 μmol/g/h under 10 °C and 10 W LED illumination. Copper and phosphorus doping that reduced (002) surface spacing of g-C3N4, resulting in thinner nanosheets. This structural modification facilitated interlayer charge transfer and suppressed photogenerated carrier recombination. This research provides a novel insight and strategy for designing hydrogen production photocatalyst at low temperatures and with low energy consumption.

Enhancing photoelectrochemical properties of α-Fe2O3 using Zr-doped HfO2 ferroelectric nanoparticles

Hematite (α-Fe2O3) as a semiconductor photoanode for photoelectrochemical (PEC) water splitting is a promising candidate material. However, its PEC performance is limited by the slow charge transfer kinetics at the α-Fe2O3/electrolyte interface. Ferroelectric materials can be used as a tool for carrier separation in photoelectrochemical water splitting due to their spontaneous polarization electric field characteristics. Here, we deposited Hf0.5Zr0.5O2 (HZO) ferroelectric nanoparticles on the surface of α-Fe2O3 and use the spontaneous polarization field of ferroelectric HZO to promote the separation of photogenerated carriers, promote the charge transfer from α-Fe2O3 to the electrolyte, and enhance the PEC of hematite. After depositing the HZO nanoparticles, the photogenerated holes are efficiently extracted from α-Fe2O3 and then directed into the electrolyte to participate in water oxidation reaction at α-Fe2O3/HZO interfaces, which enhanced the charge separation efficiency by 58 % compared to that of pure α-Fe2O3. Consequently, the α-Fe2O3/HZO photoanode exhibits a 65 % boost in photocurrent density, reaching up to 0.28 mA cm−2 at 1.23 V versus the reversible hydrogen electrode (VRHE) compared to that of pure α-Fe2O3. This study introduces a method to engineer the photoanode/ferroelectric interface, enhancing carrier separation and thereby optimizing PEC water splitting performance.

Enhancing Electrochemical Signal for Efficient Chiral Recognition by Encapsulating C60 Fullerene into Chiral Lanthanum-Based MOFs.

Chiral metal-organic frameworks (MOFs) have attracted much attention due to their highly tunable regular microporous structures. However, chiral electrochemical recognition based on chiral MOFs is often limited by poor charge separation and slow charge transfer kinetics. In this case, C60 can be encapsulated into the cavity of [La(BTB)]n by virtue of host-guest interactions through π-π stacking to synthesize the chiral composite C60@[La(BTB)]n and amplify electrochemically controlled enantioselective interactions with the target enantiomers. A large electrostatic potential difference is generated in chiral C60@[La(BTB)]n due to the host-guest interaction and the inhomogeneity of the charge distribution, leading to the generation of a strong built-in electric field and thus an overall enhancement of the conductivity of the chiral material. Their enantioselective detection of tryptophan enantiomers was demonstrated by electrochemical measurement. The results showed that chiral MOF materials can be used for enantiomeric recognition. It is worth noting that this new material derived from the concept of host-guest interaction to enhance charge separation opens up unprecedented possibilities for future enantioselective recognition and separation.

Bimodal Oxidation Electrochemiluminescence Mechanism of Coreactant-Embedded Covalent Organic Frameworks via Postsynthetic Modification.

Electrochemiluminescence (ECL) efficiency is determined by charge transfer between coreactants and emitters in coreactant systems, which are usually limited by their slow intermolecular charge transfer. In this study, a covalent organic framework (COF) with aldehyde residue was synthesized, and then coreactants were covalently integrated into the skeleton through the postsynthetic modification strategy, resulting in a crystalline coreactant-embedded COF nanoemitter (C-COF). Compared to the pristine COF with an equivalent external coreactant, C-COF exhibited an extraordinary 1008-fold enhancement of ECL intensity due to the rapid intrareticular charge transfer. Significantly, with the pH increase, C-COF shows protonation-induced ECL enhancement for the first ECL peaked at +1.1 V and an opposite trend for the second ECL at +1.4 V, which were attributed to the antedating oxidation of coreactant in framework and COF self-oxidation, respectively. The resulting bimodal oxidation ECL mechanism was rationalized by spectral characterization and density functional theory calculations. The postsynthetic coreactant-embedded nanoemitters present innovative and universal avenues for advancing ECL systems.

Bimodal Oxidation Electrochemiluminescence Mechanism of Coreactant‐Embedded Covalent Organic Frameworks via Postsynthetic Modification

AbstractElectrochemiluminescence (ECL) efficiency is determined by charge transfer between coreactants and emitters in coreactant systems, which are usually limited by their slow intermolecular charge transfer. In this study, a covalent organic framework (COF) with aldehyde residue was synthesized, and then coreactants were covalently integrated into the skeleton through the postsynthetic modification strategy, resulting in a crystalline coreactant‐embedded COF nanoemitter (C–COF). Compared to the pristine COF with an equivalent external coreactant, C–COF exhibited an extraordinary 1008‐fold enhancement of ECL intensity due to the rapid intrareticular charge transfer. Significantly, with the pH increase, C–COF shows protonation‐induced ECL enhancement for the first ECL peaked at +1.1 V and an opposite trend for the second ECL at +1.4 V, which were attributed to the antedating oxidation of coreactant in framework and COF self‐oxidation, respectively. The resulting bimodal oxidation ECL mechanism was rationalized by spectral characterization and density functional theory calculations. The postsynthetic coreactant‐embedded nanoemitters present innovative and universal avenues for advancing ECL systems.

Bifunctional NiCo-LDH cocatalyst with hole extraction and high catalytic activity for boosting photoelectrochemical water oxidation of Nd doped BiVO4 photoanode

The slow charge transfer kinetics and water oxidation dynamics hinder the efficient photoelectrochemical (PEC) water splitting of BiVO4. Here, Nd:BiVO4@NiCo-LDH photoanode was successfully prepared by introducing rare earth element Nd with a special 4 f energy level as a dopant and loading a bifunctional NiCo-LDH cocatalyst. The Nd:BiVO4@NiCo-LDH photoanode exhibits good PEC performance. The photocurrent density was 4.1 mA cm−2 at 1.23 V vs. reversible hydrogen electrode (RHE), which is about 5.1 times more than that of the unmodified BiVO4 electrode, and the onset potential was negatively shifted by 399 mV. Various physical characterizations and photoelectrochemical tests indicate that the Nd:BiVO4@NiCo-LDH photoanode has higher charge transfer rate and lower charge recombination rate than that of BiVO4. The NiCo-LDH catalyst serves as a bimetallic oxygen evolution reaction (OER) cocatalyst, where Co cation has hole extraction ability to reduce carrier recombination, and Ni addition increases the active site. The synergistic effect of the two significantly boosts the PEC water oxidation activity of the photoanode. This work has broad prospects for the construction of high-performance water oxidation systems in various photoanodes.

Hard carbon with embedded graphitic nanofibers for fast-charge sodium-ion batteries

The development of fast-charging sodium-ion batteries need the anode to have a high rate capacity with a long and reversible charging plateau at low voltage (<0.1 V). Hard carbons are extensively investigated as the anodes for sodium-ion batteries, but slow charge-transfer kinetics and low reversible capacity at low potential region are still major obstacles for their practical applications. Herein, we develop a facile strategy via in-situ carbonization of the cross-linking network of bacterial cellulose and resin to synthesize hard carbons with intrinsically embedded graphitic nanofibers. The nanostructured hard carbons anodes have a reversible capacity of 345 mAh g−1 and an ultra-large low-voltage plateau capacity of 165.5 mAh g−1 (72.7% of the reversible capacity) at 2 A g−1. Kinetics and mechanism studies reveal that the embedded graphitic nanofibers greatly boost the charge transfer and ionic diffusion, i.e. the Na+ diffusion coefficient at the plateau region can be readily improved from ≈10−10.2 to ≈10−9.0 cm2 s−1. Evidence from in/ex-situ transmission electron microscopy (TEM) demonstrates that the graphic nanofibers, with an expanded interlayer spacing, provide sufficient diffusion channels for Na+ ions’ migration and storage. Full-cell sodium-ion batteries using the nanostructured hard carbon as anodes achieve superior fast-charge capability, showing great potential applications of the nanostructured hard carbon in the low-cost and environmentally friendly energy storage devices.

Influence of O–O formation pathways and charge transfer mediator on lipid bilayer membrane-like photoanodes for water oxidation

Inspired by the function of crucial components in photosystem II (PSII), electrochemical and dye-sensitized photoelectrochemical (DSPEC) water oxidation devices were constructed by the self-assembly of well-designed amphipathic Ru(bda)-based catalysts (bda = 2,2ʹ-bipyrdine-6,6ʹ-dicarbonoxyl acid) and aliphatic chain decorated electrode surfaces, forming lipid bilayer membrane (LBM)-like structures. The Ru(bda) catalysts on electrode-supported LBM films demonstrated remarkable water oxidation performance with different O–O formation mechanisms. However, compared to the slow charge transfer process, the O–O formation pathways did not determine the PEC water oxidation efficiency of the dye-sensitized photoanodes, and the different reaction rates for similar catalysts with different catalytic paths did not determine the PEC performance of the DSPECs. Instead, charge transfer plays a decisive role in the PEC water oxidation rate. When an indolo[3,2-b] carbazole derivative was introduced between the Ru(bda) catalysts and aliphatic chain-modified photosensitizer in LBM films, serving as a charge transfer mediator for the tyrosine-histidine pair in PSII, the PEC water oxidation performance of the corresponding photoanodes was dramatically enhanced.

Enhanced levofloxacin degradation through efficient activation of peroxymonosulfate using N-doped bulged multilayer Graphene: Harnessing interface structure to regulate carrier concentration and transport speed

Nitrogen (N)-doped carbon materials are regarded as potential catalysts for advanced oxidation procedures due to their efficiency and environmentally friendly nature. Nevertheless, the low carrier concentration, slow charge transfer, and limited mass transfer efficiency hinder satisfactory catalytic performance. Herein, we present the novel use of graphite nanosheets as precursors to synthesize nanoporous N-doped mesoporous expanded and bulged multilayer graphene (EG@N-x) with varying proportions for peroxydisulfate (PMS) activation. The EG@N-2.5 catalyst demonstrates a degradation rate of 0.140 min−1, and over 90 % of LEVO (24 mg/L) was decomposed in 10 min. Additionally, the EG@N-2.5/PMS system possessed a broad pH range of efficiency (1.0–7.0), exceptional anti-interference performance against anions and humic acid (HA), and marvelous reusability, which can be attributed to the superior PMS activation performance of EG@N-x by lowering the EHOMO − ELUMO (EPD = 0.014433) gap, and reducing the adsorption binding energy (Eads = -2.33 eV), enhancing the amount of charge transfer (Q = 0.6190 e) in the EG@N-x/PMS system. The removal of LEVO is primarily attributed to the mechanism of singlet oxygen (1O2) mechanism and the metastable reactive complexes in electron transfer. Decarboxylation, defluorination, and depiperazinylation are three dominant reaction pathways. Moreover, the EG@N-x/PMS system demonstrates adequate mineralization of LEVO under various organic and environmental conditions, reducing effluent biotoxicity.

Wind-Wave Synergistic Triboelectric Nanogenerator: Performance Evaluation Test and Potential Applications in Offshore Areas.

Triboelectric nanogenerators (TENGs) can effectively collect low-frequency, disordered mechanical energy and are therefore widely studied in the field of ocean energy collection. Most of the rotary TENGs studied so far tend to have insufficient rotation, resulting in slow charge transfer rates in low-frequency ocean environments. For this reason, in this paper, we propose a wind-wave synergistic triboelectric nanogenerator (WWS-TENG). It is different from the traditional rotary TENGs based on free-standing mode in that its power generation unit has two types of rotors, and the two rotors rotate in opposite directions under the action of wind energy and wave energy, respectively. This type of exercise can more effectively collect energy. The WWS-TENG has demonstrated excellent performance in sea wind and wave energy harvesting. In the simulated ocean environment, the peak power can reach 13.5 mW under simulated wind-wave superposition excitation; the output of the WWS-TENG increased by 49% compared to single-wave power generation. The WWS-TENG proposal provides a novel means of developing marine renewable energy, and it also demonstrates broad application potential in the field of the self-powered marine Internet of Things (IoT).

Interconversion of sp-hybridized chemical bonds induces piezoelectric enhanced photocatalysis

The synergism of piezoelectric catalysis and plasmonic photocatalysis is an effective approach for enhancing the catalytic performance. Nevertheless, challenges remain in addressing the slow interfacial charge transfer rate and the high recombination of energetic hot electrons. In this study, we constructed a heterostructure comprising barium titanate/graphdiyne/gold nanofibers (BTO/GDY/Au NFs). The incorporation of a graphdiyne (GDY) layer serves as an electron sponge, significantly boosting the piezo-photocatalytic activity, with a degradation rate constant 3.3-fold higher than that of BTO/Au. Theoretical calculations indicated that BTO could undergo elastic deformation under ultrasound irradiation, resulting in the stretching and compression of GDY within a lattice constant range of 7.1–10.4 Å. This deformation induced the reversible conversion of sp-hybridized CC to CC, releasing electrons that could recombine with hot holes generated by the Au nanoparticles (Au NPs). Consequently, more hot electrons were able to participate in the catalytic reaction process. Furthermore, BTO/GDY/Au NFs demonstrated excellent catalytic performance in the rapid degradation of organic dyes and antibiotics in wastewater, while also inhibiting bacterial propagation. The above-mentioned results validated the feasibility of this heterostructure for practical applications. Overall, this study presents a novel piezo-photocatalysts, where the interconversion of sp-hybridized chemical bonds in GDY can serve as electron donor, thus significantly enhancing piezo-photocatalysis.

Accelerating Charge Kinetics in Photocatalytic CO2 Reduction by Modulating the Cobalt Coordination in Heterostructures of Cadmium Sulfide/Metal-Organic Layer.

Artificial photocatalytic CO2 reduction (CO2R) holds great promise to directly store solar energy into chemical bonds. The slow charge and mass transfer kinetics at the triphasic solid-liquid-gas interface calls for the rational design of heterogeneous photocatalysts concertedly boosting interfacial charge transfer, local CO2 concentration, and exposure of active sites. To meet these requirements, in this study heterostructures of CdS/MOL (MOL = metal-organic layer) furnishing different redox Co sites are fabricated for CO2R photocatalysts. It is found that the coordination environment of Co is key to photocatalytic activity. The best catalyst ensemble comprising ligand-chelated Co2+ with the bipyridine electron mediator demonstrates a high CO yield rate of 1523µmol h-1 gcat -1, selectivity of 95.8% and TON of 1462.4, which are ranked among the best seen in literature. Comprehensive photochemical and electroanalytical characterizations attribute the high CO2R performance to the improved photocarrier separation and charge kinetics originated from the proper energy band alignment and coordination chemistry. This work highlights the construction of 2D heterostructures and modulation of transition metal coordination to expedite the charge kinetics in photocatalytic CO2 reduction.