Carrier Surface Research Articles

Lateral junctions of transition metal dichalcogenides as ballistic channels for straintronic applications

In the context of advanced nanoelectronics, two-dimensional semiconductors such as transition metal dichalcogenides (TMDs) are gaining considerable interest due to their ultimate thinness, clean surface and high carrier mobility. The engineering prospects offered by those materials are further enlarged by the recent realization of atomically sharp TMD-based lateral junctions, whose electronic properties are governed by strain effects arising from the constituents lattice mismatch. Although most theoretical studies considered only misfit strain, first-principles simulations are employed here to investigate the transport properties under external deformation of a three-terminal device constructed from a MoS2/WSe2/MoS2 junction. Large modulation of the current is reported owing to the change in band offset, illustrating the importance of strain on the p–n junction characteristics. The device operation is demonstrated for both local and global deformations, even for ultra-short channels, suggesting potential applications for ultra-thin body straintronics.

Electrospinning preparation and characterization testing analysis of nanofiber biofilms

In order to obtain a fibrous biofilm carrier material with a good water purification effect, the biofilm carrier of PAN and PAN-PEO (mass ratio 9:1) was prepared by the electrospinning process, and the performance differences between the fabric biofilm carriers of PAN, PAN-PEO (mass ratio 9:1), and blank non-woven fabric, including the structure of biofilm carriers (surface morphology, specific surface area, and porosity), surface wettability (water contact angle and water absorbance) and membrane hanging ratio, were tested through various characterization methods. The experimental results show that the nanofiber membrane of PAN and PAN-PEO (mass ratio 9:1) prepared by the electrospinning process has a diameter of 75–375 nm, a specific surface area of 19.2 m2/g, and a porosity of 80%. The fiber diameter of non-woven fabric is in the micrometer range, with a specific surface area of 0.3659 m2/g and a porosity of 60%. This indicates that the nanofiber biofilm of PAN and PAN-PEO (mass ratio 9:1) prepared by electrospinning belongs to the carrier with a small diameter, high specific surface area, and high porosity, which can provide more attachment sites and pores for micro-organisms and is more conducive to their attachment in wastewater treatment. At the same time, the water contact angles of PAN and PAN-PEO (mass ratio 9:1) are 27.97° and 18°, respectively, and the water absorption of both reached 300%. The water contact angle of non-woven fabric is 93.32°, and the water absorption rate is only 75%. This shows that the nanofiber biofilms of PAN and PAN-PEO (mass ratio 9:1) prepared by electrospinning effectively improve the infiltration of the carrier in sewage. Finally, under the same conditions, bacterial growth and biofilm growth experiments were conducted on the nanofiber biofilm carriers of PAN and PAN-PEO (mass ratio 9:1) and the biofilm carriers of non-woven fabric. It was found that the effectiveness of the PAN and PAN-PEO (mass ratio 9:1) nanofiber biofilm carrier was significantly higher than that of non-woven fabric in treating wastewater. After 3 days of bacterial cultivation, the membrane hanging ratio of the PAN nanofiber biofilm carrier was 90.36%, the membrane hanging ratio of the PAN-PEO (mass ratio 9:1) nanofiber biofilm carrier was 82.04%, and the membrane hanging ratio of the non-woven fabric biofilm carrier was only 27.32%. After 15 days of bacterial cultivation, the membrane hanging ratio of the PAN nanofiber biofilm carrier was 147.52%, the membrane hanging ratio of the PAN-PEO (mass ratio 9:1) nanofiber biofilm carrier was 147.52%, and the membrane hanging ratio of the non-woven fabric biofilm carrier was 110.53%.

Nanoarchitectonics toward Full Coverage of CdZnS Nanospheres by Layered Double Hydroxides for Enhanced Visible-Light-Driven H2 Evolution.

Nanoarchitectonics of semiconductors shed light on efficient photocatalytic hydrogen evolution by precisely controlling the surface microenvironment of cocatalysts. Taking cadmium zinc sulfide (CZS) nanoparticles as a target, the spontaneous modifications are conducted by interactions between surface Cd2+/Zn2+ atoms and thiol groups in thioglycolic acid. The capping ligand impacts the semiconductor surface with a negative electronic environment, contributing to the full coverage of CZS by nickel-cobalt hydroxides (NiCo-LDHs) cocatalysts. The obtained core-shell CZS@NiCo-LDHs, possessing a shell thickness of ≈20nm, exhibits a distinguished topology (SBET=87.65m2g-1), long surface carrier lifetime, and efficient charge-hole separation. Further photocatalytic hydrogen evaluation demonstrates an enhanced H2 evolution rate of 18.75mmolg-1h-1 with an apparent quantum efficiency of 16.3% at 420nm. The recorded catalytic performance of the core-shell sample is 44.6 times higher than that of pure CZS nanospheres under visible light irradiation. Further density functional theory simulations indicate that sulfur atoms play the role of charge acceptor and surface Ni/Co atoms are electron donors, as well as a built-in electric field effect can be established. Altogether, this work takes advantage of strong S affinity from surface metal atoms, revealing the interfacial engineering toward improved visible-light-driven photocatalytic hydrogen evolution (PHE)activity.

Low-temperature methanation of fermentation gas with Ni-based catalysts in a multicomponent system

A large amount of greenhouse gases, such as carbon dioxide and methane, are released during the production process of bioethanol and biogas. Converting CO2 into methane is a promising way of capturing CO2 and generating high-value gas. At present, CO2 methanation technology is still in the early stage. It requires high temperature (300–400 ℃) and pressure (> 1 MPa), leading to high cost and energy consumption. In this study, a new catalyst, Ni–Fe/Al–Ti, was developed. Compared with the activity of the common Ni/Al2O3 catalyst, that of the new catalyst was increased by 1/3, and its activation temperature was reduced by 100℃. The selectivity of methane was increased to 99%. In the experiment using simulated fermentation gas, the catalyst showed good catalytic activity and durability at a low temperature and atmospheric pressure. Based on the characterization of catalysts and the study of reaction mechanisms, this article innovatively proposed a Ni–Fe/Al–Ti quaternary catalytic system. Catalytic process was realized through the synergism of Al–Ti composite support and Ni–Fe promotion. The oxygen vacancies on the surface of the composite carrier and the higher activity metals and alloys promoted by Fe accelerate the capture and reduction of CO2. Compared with the existing catalysts, the new Ni–Fe/Al–Ti catalyst can significantly improve the methanation efficiency and has great practical application potential.

The Green Preparation of Mesoporous WO3/SiO2 and Its Application in Oxidative Desulfurization

Recently, supported WO3-based catalysts have been widely used in oxidative desulfurization (ODS) due to their advantages of easy separation, high activity, and being environment-friendly. In this work, supported mesoporous WO3/SiO2 catalysts have been prepared using an incipient-wetness impregnation method with agricultural waste rice husks as both a silicon source and mesoporous template, and phosphotungstic acid as a tungsten source. The effects of different calcination temperatures and WO3 loadings on the ODS performance of samples are studied, and the appropriate calcination temperature and WO3 loading are 923 K and 15.0 wt.%, respectively. The relevant characterization results show that, compared with pure WO3, the specific surface area and mesopore volume of WO3/SiO2 samples are greatly increased. Due to (a) high WO3 loading, (b) high specific surface area, and (c) nanoscale WO3 grains uniformly dispersed on the surface of the mesoporous SiO2 carrier, active sites of WO3/SiO2 catalysts are greatly increased, and their catalytic activities are improved. After the sixth and eighth runs in the ODS of dibenzothiophene and 4,6-dimethyldibenzothiophene, respectively, the WO3/SiO2 catalyst still maintains high catalytic activity (>99.0%) despite the presence of a partial loss of WO3. In addition, with the aid of the UV-Vis technique, the tungsten-peroxo species, the active intermediates in the ODS reaction catalyzed by the WO3/SiO2 catalyst, are captured. Finally, a possible mechanism for the ODS of bulky organic sulfides using the WO3/SiO2 catalyst is proposed.

Construction of B doped g-C3N4/Ni-MOF-74 porous heterojunction with boosted carrier separation for photocatalytic H2 generation

Novel heterojunction is favored to improve the separation of photogenerated carriers and maintain high redox ability. A porous heterojunction combining porous metal-organic frameworks (MOF), Ni-MOF-74, and porous B-doped g-C3N4 (BCN) was fabricated for solar-light-driven H2 generation. The permeable surface and type-I carrier transfer mode not only created more reactive sites for H2 generation but also facilitated mass transfer at the contact interphase among BCN and Ni-MOF-74 due to a slight difference in their valence bond energy, which enhanced the excellent light trapping ability and expanded spectral absorbance range and thus solving the intrinsic drawback of fast charge recombination of pristine g-C3N4. Besides that, B-doping enhanced redox ability and transport separation, and the BCN/Ni-MOF-74 composite demonstrated dramatically reduced hydrogen production overpotential. The optimal BCN-NM-3 showed outstanding H2 generation up to 2190 μmol g−1h−1, almost 11 times higher than BCN. The current study will benefit the development of new MOF-based photocatalysts and be influential in meeting environmental demands in the future.

Enhancing Surface Modification and Carrier Extraction in Inverted Perovskite Solar Cells via Self-Assembled Monolayers.

Perovskite solar cells (PSCs) have been significantly improved by utilizing an inorganic hole-transporting layer (HTL), such as nickel oxide. Despite the promising properties, there are still limitations due to defects. Recently, research on self-assembled monolayers (SAMs) is being actively conducted, which shows promise in reducing defects and enhancing device performance. In this study, we successfully engineered a p-i-n perovskite solar cell structure utilizing HC-A1 and HC-A4 molecules. These SAM molecules were found to enhance the grain morphology and uniformity of the perovskite film, which are critical factors in determining optical properties and device performance. Notably, HC-A4 demonstrated superior performance due to its distinct hydrophilic properties with a contact angle of 50.3°, attributable to its unique functional groups. Overall, the HC-A4-applied film exhibited efficient carrier extraction properties, attaining a carrier lifetime of 117.33 ns. Furthermore, HC-A4 contributed to superior device performance, achieving the highest device efficiency of 20% and demonstrating outstanding thermal stability over 300 h.

Bio-evaluations of sericin coated hesperidin nanoparticles for gastric ulcer management

Gastric ulcers are worrying, and their worsening conditions may result in bleeding in the internal lining of the stomach. The problem is annoying, and both patients and professionals are still not satisfied with the available treatment options. Hesperidin, a flavonoid molecule with potent anti-inflammatory and antioxidant effects, can work like witchcraft to repair gastric ulcers and preserve the stomach lining. Here, we employed a strategy that involved covering the surface of the nano-lipid carriers (NLCs) with sericin before encasing the hesperidin within (Se-He-NLC). Sericin, a biodegradable polymer increases the muco-adhesion with stomach lining and deployment of hesperidin in controlled manner. Se-He-NLCs were physico-chemically characterized for drug loading, encapsulation, particle size, morphology, drug release, chemical stability, and chemical bonding. The nanocarriers showed first order drug release in a controlled manner. Se-He-NLCs showed better in vitro permeation and ex vivo mucoadhesion, thereby by promoting the in vivo bioavailability. Se-He-NLCs also promoted the reduced glutathione (GSH) and glutathione-S-transferase (GST) levels by 2.24- and 1.61-folds, respectively in the stomach lining, and also the regulation of superoxide dismutase (SOD) and catalase (CAT) activities parallel to the control group. In addition, tissues lipid hydroperoxides (LOOH) and myeloperoxidase (MPO) activity were reduced significantly with Se-He-NLCs administration. Se-He-NLC therapy of stomach ulcers in vivo demonstrated better binding ratio and ulcer healing potential. This approach reveals huge capacity for delivering therapies to treat gastric ulcers based on the clinical significance of sericin coated hesperidin nanocarriers in gastric ulcer treatment.

Experimental investigation of the effect of microwave power on the chemical looping gasification of aquatic plant water hyacinth

In this study, the gaseous products and tar characteristics of chemical looping gasification of aquatic plant water hyacinth were investigated under different microwave powers. It was found that the total gas production, the proportion of (CO and H2), and the cold gas efficiency increased from 0.54 Nm3/kg, 49.73 %, 66.52 % to 0.68 Nm3/kg, 67.76 %, and 78.66 %, respectively, as the microwave power increased from 400 to 1000 W. However, the yield of tar was reduced with the increasing microwave power. With the increase of microwave power, the specific surface area is increased due to the formation of pores on the surface of the oxygen carrier. Besides, the addition of microwave power promotes the release of lattice oxygen, which brings a higher reduction degree of Fe species in the oxygen carrier. Furthermore, the carbon attached to the surface of the oxygen carrier changes from fragmented carbon deposition to layered carbon deposition, which effectively avoids the rapid deactivation of the oxygen carrier. Therefore, the gasification reaction rate can be increased and better gas quality be obtained under higher microwave power conditions for chemical looping gasification of water hyacinth.

Unraveling FeOx Nanoparticles Confined on Fibrous Mesoporous Silica Catalyst Construction and CO Catalytic Oxidation Performance

Catalytic oxidation is used to control carbon monoxide (CO) emissions from industrial exhaust. In this study, a mesoporous silica material, KCC-1, was synthesized and used as a carrier with a high specific surface area to confine active component FeOx nanoparticles (NPs), and the CO catalytic oxidation performance of x%Fe@KCC-1 catalysts (x represents the mass loading of Fe) was studied. The experimental results showed that due to its large specific surface area and abundant mesopores, the FeOx NPs were highly dispersed on the surface of the KCC-1 carrier. The particle size of FeOx was very small, resulting in strong interactions between FeOx NPs and KCC-1, which enhanced the catalytic oxidation reaction on the catalyst. The FeOx loading improved the CO adsorption capability of the catalyst, which facilitated the catalytic oxidation of CO, with the 7%Fe@KCC-1 catalyst achieving 100% CO conversion at 160 °C. The CO catalytic removal mechanism was investigated by a combination of in-situ DRIFTS and DFT calculations. This study advances scientific understanding of the application potential of nano-catalysts in important oxidation reactions and provides valuable insights into the development of efficient CO oxidation catalysts.

Layered double hydroxide@zeolite composite modified sponge: A versatile biocarrier for enhancing nitrogen removal in biofilters

Conventional denitrification filters exhibit limited nitrogen removal efficiency in micropolluted surface waters with high dissolved oxygen levels (6 ∼ 8 mg/L). In this study, an innovative denitrification biofilter with a novel modified sponge biocarrier, composed of a layered double hydroxide@zeolite composite (LZMC) was employed to enhance the removal of nitrogen from surface waters. Based on the response surface methodology, an LZMC with high nitrogen adsorption performance was prepared. The greatest enhancement in the denitrification efficiency in the LZMC reactor was 30.62 % compared with the control reactor, and the total nitrogen removal rate reached 91.39 % under optimal conditions. Improving the carrier surface characteristics effectively boosted biofilm formation , increased biomass accumulation, and the abundance of dominant denitrifying bacteria. Additionally, the LZMC effectively accelerated electron transfer due to its high conductivity, which promoted related gene expression and enzyme activity. In conclusion, this study presents a viable route to facilitate nitrogen removal in micropolluted surface waters.

Hematite (α-Fe2O3) with Oxygen Defects: The Effect of Heating Rate for Photocatalytic Performance.

Hematite (α-Fe2O3) emerges as an enticing material for visible-light-driven photocatalysis owing to its remarkable stability, low toxicity, and abundance. However, its inherent shortcomings, such as a short hole diffusion length and high recombination rate, hinder its practical application. Recently, oxygen vacancies (Vo) within hematite have been demonstrated to modulate its photocatalytic attributes. The effects of Vo can be broadly categorized into two opposing aspects: (1) acting as electron donors, enhancing carrier conductivity, and improving photocatalytic performance and (2) acting as surface carrier traps, accelerating excited carrier recombination, and deteriorating performance. Critically, the generation rate, distribution, role, and behavior of Vo significantly differ for synthesis methods due to differences in formation mechanisms and oxygen diffusion. This complexity hampers simplified discussions of Vo, necessitating careful investigation and nuanced discussion tailored to the specific method and conditions employed. Among various approaches, hydrothermal synthesis offers a simple and cost-effective route. Here, we demonstrate a hydrothermal synthesis method for Vo introduction to hematite using a carbon source, where variations in the heating rate have not been previously explored in terms of their influence on Vo generation. The analyses revealed that the concentration of Vo was maximized at a heating rate of 16 °C/min, indicative of a high density of surface defects. With regard to photocatalytic performance, elevated heating rates (16 °C/min) fostered the formation of Vo primarily on the hematite surface. The photocatalytic activity was 7.1 times greater than that of the sample prepared at a low heating rate (2 °C/min). These findings highlight the crucial role of surface defects, as opposed to bulk defects, in promoting hematite photocatalysis. Furthermore, the facile control over Vo concentration achievable via manipulating the heating rate underscores the promising potential of this approach for optimizing hematite photocatalysts.

A novel p-type CoSe2 co-catalyst cooperated with hematite for boosting photoelectrochemical water splitting

Fe2O3-based photoelectrodes hold promise for photoelectrochemical water splitting due to their cost-effectiveness and stable chemical properties. However, Fe2O3-based photoelectrodes face limitations including low bulk conductivity and severe surface recombination of photo-generated charge carriers, which adversely affect their performance. To address these challenges, a novel p-type CoSe2 surface co-catalyst was developed to establish a Ti-Fe2O3/CoSe2 p-n heterojunction. By incorporating a Ti4+ doping strategy, the resulting Ti-Fe2O3/CoSe2 p-n heterojunction demonstrated a significant increase in photocurrent density, reaching 2.85 mA/cm2 at 1.23 VRHE under 100 mW/cm2 illumination. The corresponding IPCE achieved 60.14 % under 365 nm light irradiation, nearly 5 times higher than that observed on pristine Fe2O3. Besides Ti4+ dopant, the improvement can be attributed to the p-type CoSe2 surface co-catalyst, which created a built-in electric field at the interface between CoSe2 and Ti-Fe2O3, effectively suppressing electron tunneling from the photoelectrode to the electrolyte and reducing surface carrier recombination. This study improves our understanding of the water splitting catalytic reaction on CoSe2-derived heterojunctions and provides insights for the rational design of photoelectrodes used in photoelectrochemical water splitting.

Study on process and mechanism of cordierite recovery by flotation from spent automobile catalysts

Flotation, as one of the most likely methods to improve the recovery efficiency of cordierite from spent automotive catalysts, requires systematic research and optimization. In this study, an efficient flotation process with cordierite recovery of 85.2 % was proposed. The mechanism of flotation was studied by SEM-EDS, XPS, AFM. SEM-EDS confirmed that Si distributed mainly in the cordierite carrier of spent automotive catalysts and Al (not in cordierite structure) distributed mainly in the washcoat. XPS results showed that the adsorption strength of NaOL (sodium oleate) was greater than that of Na2O⋅3SiO2 (sodium silicate) on the surface of washcoat. AFM results showed that the adsorption effect of Na2O⋅3SiO2 was stronger than that of NaOL on the surface of cordierite carrier. In summary, internal reasons to realize cordierite recovery from spent automobile catalysts by flotation were the selective adsorption of NaOL on the surface of washcoat and Na2O⋅3SiO2 on the surface of cordierite.

Investigation of Phosphorus Spin on Dopant on SOI Wafer

Silicon on insulator (SOI) wafer has allowed the integrated circuit (IC) industry to create superior, high-performance solutions. In addition, doping techniques are vital in the silicon sector due to the need to regulate the material electrical properties. The spin on dopant (SOD) approach is an alternative method that involves spinning a solution containing dopant onto SOI wafers. This research aims to determine the impact of thermal diffusion temperature and soaking time on sheet resistance of doped SOI wafer using SOD approach. Additionally, the homogeneity of doping was studied by utilizing mapping techniques. Three inches boron-doped SOI wafers were cut and cleaned according to Radio Corporation of America (RCA) standards. N-type dopants of Filmtronics SOD P509 were deposited on SOI wafer by using a spin coater, for 40 seconds at 4,000 revolutions per minute (rpm). The thermal diffusion temperature and soaking time were set between 700°C to 1000°C for 30 to 120 minutes. After thermal diffusion, hydrofluoric acids (HF) were diluted and used to etch samples. All materials were evaluated using a four-point probe, Hall Effect and Atomic Force Microscope (AFM). The results show that when the thermal diffusion soaking time increases, sheet resistance decreases until activated dopants are saturated. When sheet resistance decreases, dopant concentration rises. Temperature and soaking time increase carrier density and surface roughness, while decreasing Hall mobility. From mapping techniques, it shows low non-uniformity value which less than 10% suggests good thermal diffusion control.

Multi-level optimization of biomass chemical looping gasification process based on composite oxygen carrier

Biomass chemical looping gasification (BCLG) is one of the essential technology to utilize renewable resources, but the current lack of in-depth research on BCLG makes it difficult for practical industrial applications. In this paper, the combination of quantum chemical calculation, ReaxFF molecular dynamic (ReaxFF MD) simulation, and process simulation is used to conduct an in-depth study of BCLG process. Firstly, three composite oxygen carriers (CuFe2O4, CoFe2O4, and Fe3O4) are selected by density functional theory (DFT), which finally indicates that CuFe2O4 is the best composite oxygen carrier for BCLG. Then, the reaction mechanism between syngas and oxygen carrier surface is studied at the microscopic level, which validates the high performance of CuFe2O4. After determining the oxygen carrier, the reaction mechanism of BCLG and the effect of temperature on the product distribution are studied by ReaxFF MD simulation. Finally, the process simulation of BCLG is constructed based on the results discussed above.

Submerged macrophyte promoted nitrogen removal function of biofilms in constructed wetland

Biofilm is one of the important factors affecting nitrogen removal in constructed wetlands (CWs). However, the impact of submerged macrophyte on nitrogen conversion of biofilms on leaf of submerged macrophyte and matrix remains poorly understood. In this study, the CWs with Vallisneria natans and with artificial plant were established to investigate the effects of submerged macrophyte on nitrogen conversion and the composition of nitrogen-converting bacteria in leaf and matrix biofilms under high ammonium nitrogen (NH4+-N) loading. The 16S rRNA sequencing method was employed to explore the changes in bacterial communities in biofilms in CWs. The results showed that average removal rates of total nitrogen and NH4+-N in CW with V. natans reached 71.38% and 82.08%, respectively, representing increases of 24.19% and 28.79% compared with the control with artificial plant. Scanning electron microscope images indicated that high NH4+-N damaged the leaf cells of V. natans, leading to the cellular content release and subsequent increases of aqueous total organic carbon. However, the specific surface area and carrier function of V. natans were unaffected within 25 days. As a natural source of organic matters, submerged macrophyte provided organic matters for bacterial growth in biofilms. Bacterial composition analysis revealed the predominance of phylum Proteobacteria in CW with V. natans. The numbers of nitrifiers and denitrifiers in leaf biofilms reached 1.66 × 105 cells/g and 1.05 × 107 cells/g, as well as 2.79 × 105 cells/g and 7.41 × 107 cells/g in matrix biofilms, respectively. Submerged macrophyte significantly increased the population of nitrogen-converting bacteria and enhanced the expressions of nitrification genes (amoA and hao) and denitrification genes (napA, nirS and nosZ) in both leaf and matrix biofilms. Therefore, our study emphasized the influence of submerged macrophyte on biofilm functions and provided a scientific basis for nitrogen removal of biofilms in CWs.

Vertical plane depth‐resolved surface potential and carrier separation characteristics in flexible CZTSSe solar cells with over 12% efficiency

AbstractCu2ZnSn(S,Se)4 (CZTSSe) solar cells have resource distribution and economic advantages. The main cause of their low efficiency is carrier loss resulting from recombination of photo‐generated electron and hole. To overcome this, it is important to understand their electron‐hole behavior characteristics. To determine the carrier separation characteristics, we measured the surface potential and the local current in terms of the absorber depth. The elemental variation in the intragrains (IGs) and at the grain boundaries (GBs) caused a band edge shift and bandgap (Eg) change. At the absorber surface and subsurface, an upward Ec and Ev band bending structure was observed at the GBs, and the carrier separation was improved. At the absorber center, both upward Ec and Ev and downward Ec‐upward Ev band bending structures were observed at the GBs, and the carrier separation was degraded. To improve the carrier separation and suppress carrier recombination, an upward Ec and Ev band bending structure at the GBs is desirable.

Food enrichment with trace elements by immobilizing them on the surface of a biopolymeric carrier

Food enrichment with trace elements by immobilizing them on the surface of a biopolymeric carrier

Enhancing the efficiency of PVDF-based piezoelectric catalysis through water-induced polarization and a micro-nano-composite strategy.

Polyvinylidene fluoride (PVDF)-based piezoelectric catalysts show promise in mechanical force-driven catalysis due to their good biocompatibility, flexibility, and ease of fabrication. However, the catalytic activity of pristine PVDF is limited due to its low piezoelectric phase content (<20%), poor orientation, and low surface carrier concentration. Here, we introduce an efficient PVDF-based composite nano-catalyst (rGO/PVDF) with high piezoelectric catalytic performance. We achieve this by employing a composite strategy that combines nanoscale water-induced polarization with polar functional group-modified graphene (rGO) serving as a nanoelectrode. The nanoscale water polarization effect, together with the two-dimensional planar structure of PVDF and the modified graphene's polar functional groups, effectively induces orientation in the PVDF piezoelectric phase to increase the functional β phase content. As a result, the β phase content and crystallinity of rGO/PVDF reach 95% and 40%, respectively, which are 600% and 170% higher compared to those of pristine PVDF. This enhancement plays a crucial role in endowing the material with strong force-to-electricity conversion characteristics. Additionally, the surface-modified rGO also boosts PVDF's surface carrier concentration and provides active sites for catalysis on the rGO/PVDF composite. Notably, under optimized conditions, our catalyst achieves a ∼99.1% degradation rate of organic pollutants (10 mg L-1) after 12 minutes of sonication at 240 W and maintains a high efficiency of ∼93.7% even at a 10 times higher pollutant concentration (100 mg L-1). Our piezoelectric catalyst also demonstrates efficient H2O2 production at 95.8 mmol grGO-1 h-1, which is ∼9-fold and ∼134-fold higher than those of untreated PVDF and previously reported PVDF-based piezoelectric catalysts, respectively. This work paves the way for the development of highly efficient PVDF-based piezoelectric catalysts, thereby offering valuable insights for the advancement of mechanically driven catalysis in the environmental, energy, and chemical sectors.