Search

• A three-dimensional photoanode was designed with crystal facets modulation. • Crystal facets modulation favors charge separation and •OH radical desorption. • Fluid dynamics simulation showed the enhanced mass transfer on the mesh substrate. • Efficient elimination of 5-fluorouracil was achieved by photoelectrocatalysis. • A 1200 cm2 photoelectrocatalytic system was tested for the applied feasibility. Fluorinated pharmaceuticals pollution has become an ever-increasing environmental concern due to its negative impacts. Photoelectrocatalytic (PEC) degradation system is a desirable approach to tackle the pollution problems. However, photogenerated charge separation and interfacial mass transfer are the main bottlenecks for improving the PEC degradation performance. Herein, we report a TiO 2 photoanode with tuned (101)/(110) facets in situ grown on a Ti mesh substrate for PEC degradation of fluorinated pharmaceuticals. The exposure of (101) facets facilitates efficient photogenerated charge separation and the desorption of generated •OH radical. Besides, the three-dimensional (3D) architecture of photoanode promotes macroscopic mass transfer. This system performed complete defluorination of 5-fluorouracil and more than 75 % total organic carbon (TOC) removal efficiency. The apparent reaction rate constant of high (101) facet-exposed TiO 2 grown on Ti mesh is up to 6.96 h −1, 6‒fold faster than that of photoanode with low (101) facet-exposed TiO 2 grown on Ti foil. It is demonstrated that a large-sized PEC system of 1200 cm2 can degrade 100 L of synthetic fluorinated pharmaceutical wastewater with more than 80 % elimination efficiency. This work showcases the facet and substrate modulated strategy of fabricating high-performed photoanode for PEC wastewater purification. [Display omitted] [ABSTRACT FROM AUTHOR]

Electrocatalytic CO 2 reduction reaction (CO 2 RR) to produce multi-carbon products (C 2+) is one of the most sustainable manners to achieve net-zero carbon emissions. Among many approaches, enriching grain boundaries (GBs) in copper (Cu) catalysts has been demonstrated to enable enhancement for C 2+ production. However, it still lacks effective strategies to controllably synthesize abundant GBs, rendering efficient C 2+ production a persistent challenge, especially at ampere-level current density. Herein, we propose a novel strategy, which can achieve unconventional grain fragmentation during thermal annealing and thus create controllable GB densities. The catalyst with the utmost GB density exhibits a peak C 2+ faradaic efficiency of ca. 70.0 % in H-type cell and 68.2 % in flow cell; even more impressively, it delivers an ultra-high C 2+ current density of 0.768 A cm−2, outperforming most recently reported results. A combination of in situ spectroscopies and theoretical calculations reveal that the enrichment of GBs yields more active sites for a higher *CO coverage, leading to promotion of the *CO-*CO coupling process and ultimately high C 2+ production performance. [Display omitted] • An unconventional grain fragmentation strategy is proposed to controllably tune the density of Cu GBs. • The optimal catalyst exhibits a C 2+ current density of 0.768 A cm−2, outperforming most reported counterparts. • The high C 2+ production stems from a higher *CO coverage and more facile *CO-*CO coupling over Cu GBs. [ABSTRACT FROM AUTHOR]

Rational design of highly efficient photocatalysts for CO 2 conversion into carbonaceous fuels is of great significance to mitigate the global greenhouse effect and energy shortage problem. Among numerous materials studied for this purpose, the carbon nitride (g-C 3 N 4) has been widely used in photocatalytic CO 2 reduction (PCR) due to its decent optical properties, low cost and environment friendliness. However, its wide use still remains a substantial challenge due to inefficiency of the active site and rapid recombination of photogenerated electrons and holes. Herein, we suggest a Z-scheme system of nitrogen vacancies g-C 3 N 4 /β-Bi 2 O 3 heterojunction photocatalyst based on self-assembly of nitrogen vacancies in g-C 3 N 4 nanosheets and β-Bi 2 O 3 micro-flowers, yielding an enhanced CO evolution rate of 30.56 μmol·g−1·h−1 under the simulated solar light without any cocatalysts and sacrificial agents. Our detailed studies indicate that the promoted PCR performance originates from the stronger adsorption capability of the *COOH intermediates due to the cleavage of the C-C bond in nitrogen vacancies g-C 3 N 4 (N V -C 3 N 4), turning the most endothermic step from the formation of *COOH intermediates to *CO. Moreover, the unique Z-scheme feature can efficiently facilitate the separation of photoelectron-hole pairs and enhance redox capability by optimizing the energy band structure. To sum up, this work provides deep insights and guidelines for rational design of highly efficient Z-scheme heterojunctions catalysts for CO 2 photoreduction to solar fuels. [Display omitted] • Synergistic nitrogen vacancy and Z-scheme heterojunction strategy are introduced in g-C 3 N 4 /β-Bi 2 O 3 photocatalysts. • Newfangled dynamic evolution of nitrogen vacancy boosts the intrinsic activity. • Unique Z-scheme heterojunction greatly promotes the charge separation ability. • In situ DRIFT and DFT simulation uncover the mechanisms of CO 2 photoreduction. [ABSTRACT FROM AUTHOR]

Strain engineering involves intentionally inducing lattice distortion in materials to manipulate their electronic and geometric properties, along with the accompanying bond strength between reactants and catalysts. This approach presents an appealing pathway to optimize catalytic performance. However, it confronts challenges in achieving precise control, scalability and controllable modulation of intermediate species' adsorption and desorption. Herein, we report a dynamic strain engineering method achieved through ultrasonic cavitation-induced high and low-pressure cycles, enabling periodically adjustable adsorption/desorption properties while bypassing complex synthesis procedures. Illustrated using ZnO and CO 2 piezo-reduction reaction as a demonstration, theoretical studies initially predict that adsorption of intermediates *COOH can be regulated within a specific range of strains. Under ultrasonic stimulation, ZnO catalyst with dynamic strain engineering exhibits a CO yield of ∼ 98.8 μmol·g−1·h−1, approximately 16.5 times higher than that achieved under ultraviolet light irradiation without dynamic strain engineering, despite the latter having a considerably stronger input power. Furthermore, we delve into the factors linked to dynamic strain amplitude and frequency. This dynamic strain engineering approach streamlines catalyst preparation and presents innovative possibilities for controlled manipulation of intermediate specie's adsorption/desorption, with potential applications across a wide range of catalytic systems. [Display omitted] • A dynamic strain engineering strategy for periodically tailoring adsorption between catalysts and intermediates is proposed. • This strategy eliminates the bygone need for complex catalyst synthesis and can be universally applied to any catalyst. • The underlying mechanism for the enhanced CO 2 conversion via such strategy is investigated. [ABSTRACT FROM AUTHOR]

The overreliance on non-renewable energy sources like fossil fuels has led to severe energy crises and environmental pollution, hindering sustainable development. Harnessing solar energy for water splitting through semiconductor photocatalysts offers a promising solution. Titanium dioxide (TiO 2), a benchmark photocatalyst, is favored for its cost-effectiveness, non-toxicity, and stability under ultraviolet light. However, its weak light absorption, limited range, and high carrier recombination rates pose challenges. Herein, we designed an Au nanoparticle modified TiO 2 (Au/TiO 2) using a two-step method involving initial stirring adsorption followed by calcination. This composite material exhibits a localized surface plasmon resonance property, demonstrating powerful light absorption capacity in both the visible and near infrared regions. Moreover, following the decoration of Au nanoparticles, in situ XPS reveal Au/TiO 2 exhibits a metal-support interaction, thereby enhancing the separation and migration of photogenerated carriers and decreasing the recombination rate of photogenerated charges. Thus, Au/TiO 2 shows a photocatalytic hydrogen evolution rate of 47.89 mmol g−1 h−1, which is 39.25 times higher than that (1.22 mmol g−1 h−1) of pristine TiO 2 and among the top rankings of TiO 2 -based photocatalysts. This study provides a novel approach to developing a photocatalyst capable of absorbing a broad spectrum of solar energy. [ABSTRACT FROM AUTHOR]

Piezo-electrocatalytic CO 2 reduction reaction (PECRR) technique has been verified as an effective CO 2 -to-fuel conversion strategy by exploiting and utilizing the widely distributed mechanical energy in nature, e.g., blue energy. The facile large-scale preparation of high-performance and low-cost piezo-electrocatalysts is therefore highly desired but challenging. Herein, a method of physical mixing of piezo-electrocatalysts and earth-abundant carbon-based materials is proposed to address the above issue, and we verified this method with typical piezoelectric BaTiO 3 and graphene oxide (GO) as a demonstration. With an optimized GO concentration, the BaTiO 3 shows a CO yield of 134.4 μmol g−1 h−1 which is about 45.3 % higher than that of pristine BaTiO 3. The mechanisms for the enhancement are revealed via boosted piezo-carrier dynamics and charge transfer from BaTiO 3 to GO as well as enhanced intrinsic activity. Furthermore, physical mixing of GO is extended to other piezo-electrocatalysts (MoS 2 , ZnO, ZnS, CdS, Bi 2 WO 6), from which it is found that their performance is improved compared to the counterpart of those without GO. This work suggests that the physical mixing GO is a universal method to improve PECRR performance and may be a decent candidate approach for large-scale preparation of high-performance and low-cost piezo-electrocatalysts in future. [Display omitted] • A facile physical mixing method boosting piezo-electrocatalytic CO 2 conversion performance is reported. • Charge transfer behavior between BaTiO 3 and graphene oxide is evidenced via a piezo-deposition experiment. • The method shows great potential in general large-scale preparation of high-performance and low-cost piezo-electrocatalyst. [ABSTRACT FROM AUTHOR]

In this work, the bi-harvesting of light and vibration energy is realized in hydrothermally-synthesized ZnO nanorods which is designed to achieve photo-/piezo-bi-catalysis for dye decomposition. In the presence of both UV irradiation and vibration, the decomposition ratio of ZnO nanorods for acid orange 7 is ∼80.8% within 100 min, which is higher than the value of ∼56.7% for photo-catalysis or the value of ∼31.8% for piezocatalysis. The enhanced photo-/piezo-bi-catalysis of ZnO nanorods in dye decomposition can be attributed to that the piezoelectric potential which formed in piezocatalysis process can help separate the photogenerated electron-hole pairs, therefore achieving a synergy effect between photocatalysis and piezocatalysis. The excellent photo-/piezo-bi-catalysis of ZnO can potentially find application in enhancing catalytic efficiency of dye decomposition through harvesting the light and vibration energy present in natural environments. Image 1 • Bi-harvesting light/vibration energy using hydrothermally-synthesized ZnO nanorods is realized. • Bi-catalysis for dye decomposition is better than photocatalysis or piezocatalysis alone. • ZnO is potential for dye wastewater remediation through harvesting ambient light/vibration energy. [ABSTRACT FROM AUTHOR]

In this study, strong pyro-driven catalysis for dye wastewater remediation is achieved by using Pb(Zr 0.52 Ti 0.48)O 3 (PZT) polarized ceramic via pyroelectric effect. Through cyclic heating–cooling (301–333 K) of PZT ceramic, decomposition ratio of Rhodamine B dye reached up to ∼98% after 140 cold–hot cycles. Active species hydroxyl radical was detected, providing the evidence for continuous generation of pyroelectrically induced electric charges. After recycling for three times, PZT ceramic shows no decrease in pyro-driven catalysis activity. PZT ceramic has advantages of high efficiency and easy recycling, thus making it potential candidate for dye wastewater remediation by utilizing ambient thermal energy in the future. Image 1 [ABSTRACT FROM AUTHOR]

Abstract In this work, an unambiguous pyroelectrically-induced pyrocatalysis in hydrothermally-synthesized BaTiO 3 (BTO) nanofibers with or without noble metal loading (BTO@Ag and BTO@Pd) is found and its application for the decomposition of Rhodamine B dye under thermal cycling near room-temperature is also developed. The pyrocatalytic decomposition ratios of BTO, BTO@Ag and BTO@Pd are ~ 48%, ~ 92% and ~ 95%, respectively, under 72 cold-hot (30–52 °C) thermal cycles. In the pyrocatalytic process, the detected main active species are holes, hydroxyl radicals and superoxide radicals. The enhanced pyrocatalysis is attributed to noble metals that trap the transferred electrons from the BTO surface, promoting charge separation. No obvious loss of pyrocatalytic activity is observed after 5 cycles, indicating good stability of BTO@Ag and BTO@Pd nanofibers. The enhanced pyrocatalytic performance makes BTO@Ag and BTO@Pd nanofibers potential in purifying dye waste pollution through utilizing cold-hot fluctuation thermal energy. [ABSTRACT FROM AUTHOR]

The development of advanced photocatalysts for CO 2 reduction (CO 2 R) has attracted intensive interest but is severely plagued by the intrinsically narrow photo-responsive range, inefficient carrier separation of the current supports. Herein, the unconventional atomic surface concaves with Bi-O-Br complex vacancies on thin Bi 5 O 7 Br nanotubes were designed and successfully synthesized. This concave-rich structures provide electron localized enrichment regions that could address the above two issues simultaneously. The unique concaves serve as the active sites that enable the exceptional capacity for the capture and activation of CO 2 and the formation of key intermediates. Ultimately, an ultrahigh CO yield rate of 30.96 μmol g−1 h−1 was obtained under ambient conditions without anchoring extra metal active species or any sacrificial agents. Our work not only provides a promising support but also proposes a unique structure to optimize the photocatalytic performance. [Display omitted] • Atomic "-Bi-O-Br-" concave engineering is introduced in Bi 5 O 7 Br photocatalysts. • Charge localization induced by concave greatly enhanced CO 2 capture capacity. • Multifunctional improvement of carrier dynamics and surface reaction is achieved. • In situ DRIFT and DFT simulation uncover the mechanisms of CO 2 photoreduction. [ABSTRACT FROM AUTHOR]

Photocatalytic H 2 generation is an effective approach to convert solar energy into renewable H 2 energy and has drawn great attentions. To improve the catalytic activity, lots of attentions have been paid to developing advanced strategies, of which oxygen vacancy engineering is considered as a promising one. However, oxygen vacancy induced coexistence of defect and strain makes understanding the essential mechanism of enhanced photocatalytic performance elusive and challenging. Here, the classic photocatalyst TiO 2 is selected as a paradigm to reveal the relationship between the accompanied defect and strain in boosting H 2 generation activity. It is found that oxygen vacancy concentration almost shows a volcano-type trend, while strain exhibits a monotonic decrease with increasing the calcination temperature. An optimal photocatalytic H 2 yield of 788 μmol g−1 h−1 is achieved over the TiO 2 with high oxygen vacancy concentration but slight strain. This value is 2.5 times higher than the counterpart with low oxygen vacancy concentration and large strain, indicating that oxygen vacancy induced defect instead of strain plays the dominate role in enhancing photocatalytic H 2 generation, which is further verified by theoretical calculations and experimental carrier dynamics analysis. This work uncovers the relationship between defect and strain in oxygen vacancy-engineered photocatalysts. With the increasing calcination temperature, oxygen vacancy-induced defect and strain, revealing that defect plays a dominate role in the photocatalytic H 2 generation of TiO 2 nanoparticles. [Display omitted] • Oxygen vacancy is introduced in typical TiO 2 photocatalysts. • With the increase of temperature, defect firstly increases and then decreases. • TNP-750 with high V O concentration and slight strain shows the maximum H 2 yield. • DFT verifies that V O concentration plays a dominate role in H 2 generation. [ABSTRACT FROM AUTHOR]

Constructing dual sites is promising to break scaling relations between the adsorption energetics of reaction intermediates and ultimately improves the activity and selectivity due to the synergistic effect. However, it is a grand challenge to precisely form a dual-site configuration with one metal site adjacent to another active site. Loading single atoms onto oxides with pre-introduction of surface oxygen vacancies may be an alternative strategy to overcome such challenge. Motivated by our theoretical calculations that the dual sites formed by single Cu atoms and unsaturated Ti sites on TiO 2 enables a higher activity towards hydrogen evolution from water splitting than corresponding single site, we successfully synthesized a Cu 1 -Ti dual-site catalyst by depositing Cu single atoms on TiO 2 nanoparticles with abundant surface oxygen vacancies. The designed target catalyst significantly outperforms the benchmark Pt nanoparticle decorated TiO 2 with a high and stable activity towards photocatalytic hydrogen production. [Display omitted] • Theoretical calculations revealed that Ovs promote water dissociation and single Cu atoms promote hydrogen evolution. • The designed target catalyst exhibited extraordinarily high activity and excellent stability for photocatalytic H 2 evolution. • The method provide a paradigm that precisely combines single atoms with substrate metal sites to generate active dual sites. [ABSTRACT FROM AUTHOR]

Understanding on the photogenerated charge separation from a microscopic level remains a challenge and is highly desirable as it provides a cornerstone for designing high-performance photocatalysts. Herein, facet engineering is chosen as a tool to reveal the relationship between the charge separation/transfer and crystal structure. A series of BiOBr nanosheets with dominantly exposed facet of (001) or (010) as well as different lateral facet exposure ratios are constructed via adjusting pH value during the hydrothermal process. It is found that exposure of anisotropic crystal facets allows the separative transfer of photogenerated electrons and holes onto the lateral facets and dominantly exposed facets, respectively, which is attributed to the junction formed between distinct facets (i.e., facet junction). In the case of BiOBr-5 with (010)/(102) facet junction, the electron transfer rate (k ET) and efficiency (η ET) are 3.658 × 106s−1 and 54.09%, which are superior than the counterpart of BiOBr-1 with (001)/(110) facet junction. The fast electron transfer rate and high transfer efficiency of BiOBr-5 result in the high CO evolution rate from CO 2 photoreduction under artificial sunlight. Our work may bring some new insights into the mechanism of facet junction and rational design of photocatalysts with high performance for solar energy storage in future. The (010)/(102) facet junction on the BiOBr nanosheet was used for efficient charge separation and transport. its fast electron transfer rate and high transfer efficiency result in the high CO evolution rate from CO 2 photoreduction under artificial sunlight. Our work may bring some new insights into the mechanism understanding of facet junction and rational design of photocatalysts with high performance for solar energy storage in future. [Display omitted] • BiOBr nanosheets with different facet junctions were synthesized for photocatalytic CO 2 reduction. • The (010)/(102) facet junction presents more favorable charge separation and transfer performance than (001)/(110). • Such charge separation in (010) / (102) facet junction facilitates the efficient conversion of CO 2 into CO. [ABSTRACT FROM AUTHOR]

In this work, a novel pyroelectric catalysis technique is developed for decomposition of dye wastewater using the lead-free (K 0.5 Na 0.5)NbO 3 pyroelectric crystal catalyst under the environmental temperature variation. 91.2% of rhodamine B dye can be decomposed after (K 0.5 Na 0.5)NbO 3 pyroelectric catalyst undergoing 100 cold-hot 30–60 °C cycles. The catalytic activity can be obviously influenced by the poling electric field of catalyst materials. With the increase of the poling electric field from 0 to 4.5 kV/mm, the dye decomposition ratio correspondingly increases from 3.3% to 91.2%. The poling treatment is helpful to enhance the polarization of the (K 0.5 Na 0.5)NbO 3 crystal, which can also result in the increase of the pyroelectric coefficient, yielding to the enhancement of pyroelectric catalysis. The scavenger experiments are carried out, in which the main active species in the pyroelectric catalysis are found to be superoxide radicals, hydroxyl radicals and holes. The effects of various factors including dye concentration, catalyst dosage, pH and type of dyes on pyroelectric catalysis performance of (K 0.5 Na 0.5)NbO 3 are also investigated to obtain the optimum condition. The results of three consecutive recycling-utilization tests indicate that (K 0.5 Na 0.5)NbO 3 crystal possesses good chemical stability. With these advantages of high dye decomposition ratio and good recycling utilization, (K 0.5 Na 0.5)NbO 3 crystal is potential in developing the novel pyroelectric catalysis technique for decomposition of dye wastewater through utilizing the thermal energy from the environmental cold-hot temperature variation in future. Image 1 • Temperature variation-induced pyroelectric catalysis is discovered in (K 0.5 Na 0.5)NbO 3 crystal. • The pyroelectric catalysis of (K 0.5 Na 0.5)NbO 3 can be influenced through electric poling. • Electric field poling shows great potential in the preparation of pyroelectric catalysts. • It is desirable to realize dye wastewater purification through ultilizing cold-hot alternation. [ABSTRACT FROM AUTHOR]

In the suspensions with the Ba 0.75 Sr 0.25 TiO 3 (BST) nanoparticles with an average size ~20 nm for triboelectric energy harvesting, dye decompositions were found to occur readily in the course of a normal stirring in dark at room temperature. More importantly, the decomposition efficiency can be greatly improved through some simple modifications in stirring rods and as high as 99.0% Rhodamine B can be decomposed in 3 h under a mild stirring of 300 rpm. Some well-designed experiments have been conducted, which show that the observed dye decompositions are directly related to the friction between BST nanoparticles and stirring rods in magnetic stirring. It is proposed that with the mechanical energy absorbed from friction, the BST nanoparticles have exerted a novel tribocatalytic effect for dye decompositions, which is confirmed by the detection of intermediate products of •OH and •O 2 − in stirring. These results clearly demonstrate that nanostructured oxides have the capability to harvest mechanical energy from ambient environment through friction for dye decomposition, which represents an important application for harvesting mechanical friction energy. Image 1 • Tribocatalytic dye decomposition of Ba 0.75 Sr 0.25 TiO 3 nanoparticles is realized in suspensions under friction. • Dye decomposition efficiency can be greatly improved through some modifications in stirring rods. • The tribocatalysis is originated from the triboelectricity between Ba 0.75 Sr 0.25 TiO 3 nanoparticles and plastic rods. • The novel tribocatalysis is potential in wastewater treatment through harvesting environmental frication energy. [ABSTRACT FROM AUTHOR]

The aim of this paper is to experimentally and analytically evaluate the hysteretic behavior of steel plate deep beams infill steel frame. Three reduced-scale specimens subjected to cyclic loading have been tested and their responses measured and analyzed. The test results showed the good behavior of the steel plate deep beams infill steel frame, mainly improving the strength, stiffness, ductility and energy dissipation capacity of the steel frame. Then parametric studies, using a finite-element analysis program, were carried out to investigate the structural behavior with variations in: forms of stiffeners, height-width ratio α, height-thickness ratio β , and the size of the column and beam. The numerical results indicate that the parameters of full stiffeners, including cruciform and bilateral stiffeners, α = 0.75, β = 150 are reasonable for use in steel plate deep beams infill steel frame. [ABSTRACT FROM AUTHOR]

Background: No meta-analysis has analyzed the effect of physical activity level, period of physical activity intervention, and duration of intervention, on perinatal depression. This study was to evaluate the impact of physical activity intensity, dose, period, and duration on perinatal depression.Methods: The literature was searched via the PubMed, Embase, Cochrane Library, and Web of Science databases. Weighted mean difference (WMD) or the risk ratio (RR) was used as the effect indicator, and the effect size was represented by the 95 % confidence interval (CI). Subgroup analysis based on the perinatal stage, physical activity intensity, physical activity equivalent, and intervention duration was performed.Results: Totally, 35 studies including 5084 women were included. Physical activity could reduce the incidence and severity of depression in perinatal women. Among depressed women with prenatal depression, low-intensity physical activity, with metabolic equivalents (METs)-min/week being <450, was associated with lower levels of depression. In the general population, the risk of postpartum depression was lower in the physical activity group when the duration of intervention was ≥12 weeks, being II, III stage, and ≥450 METs-min/week. Both low and moderate-intensity physical activity were beneficial to an improved depression severity among depressed women with postpartum depression, and moderate exercise intervention could decrease the risk of postpartum depression in general pregnant women.Limitations: Different types of physical activities may affect the effectiveness of interventions.Conclusion: Our study indicated physical activity specifically targeted at pregnant women could reduce depression risk and severity. [ABSTRACT FROM AUTHOR]

• Path dependency of some technologies might have "lock-in" effect of health impacts. • A pollution control technology scheme dominates in the coal-fired power sector. • Alternative control technology schemes with better net present value exist. • Single-technology-domination can pose long-term risks of economic efficiency loss. • Policy transition could improve the economic efficiency of pollution control. The broad spectrum of environmental protection technologies and their health effects have increased concern about path dependency and the "lock-in" effect. This study focuses on China's coal-fired power plants and their air pollution control technologies, due to the challenge of technology deployment in this sector. Our analysis found that there is a dominant technology scheme of air pollution control in the sector. Alternative schemes with better Net Present Value (NPV) exist beyond the dominant scheme, meaning that long-term economic efficiency is lost by implementing the current mainstream scheme. Facing the complexity and uncertainty around air pollution and climate change, this study suggests that single-technology-dominated environmental protection can pose long-term economic efficiency risks. This paper further points out the implications of technology policy improvement: paying attention to the synergy effects of air pollution technologies, the cultivation of technology diversity, the links between pollution control technology and public health objectives, and cost-benefit analysis together with NPV comparison. [ABSTRACT FROM AUTHOR]

In this work, it is found that the hydrothermally-synthesized bismuth oxychloride can behave both the piezocatalysis and photocatalysis for the Rhodamine B dye decomposition. ∼99% decomposition efficiency is achieved after both vibrating and lighting the Rhodamine B dye solution for ∼96 min with the addition of bismuth oxychloride catalyst, while the ∼72% and ∼26% decomposition efficiencies are obtained for only photocatalysis or only piezocatalysis respectively. In bi-catalysis, the mechanical strain produced due to vibration will directly provide an electric field that will increase the separation between the photo-induced electron-hole pairs, yielding to the enhanced decomposition performance of bi-catalysis. There is no significant change in the bi-catalytic performance of bismuth oxychloride nanomaterial observed after being recycled four times. Bismuth oxychloride catalyst is potential for the bi-catalytic decomposition treatment of wastewater through harvesting both the environmental vibration energy and light energy. Image 104650 • The BiOCl nanomaterials were hydrothermally synthesized. • High-efficient synergy of piezocatalysis and photocatalysis was realized. • Bi-catalysis is superior to piezocatalysis or photocatalysis in dye decomposition. • BiOCl is potential in utilizing vibration/light energy to decompose dye solution. [ABSTRACT FROM AUTHOR]

In this work, the hydrothermally-synthesized sodium niobate nanowires were used to decompose Rhodamine B dye solution through the piezo-catalytic effect. With the sodium niobate catalyst, a high piezo-catalytic degradation ratio of ∼80% was achieved under the excitation of vibration for the Rhodamine B dye solution (∼5 mg/l). These active species in the catalytic process, hydroxyl radicals and superoxide radicals with the strong oxidation ability, were also observed, which confirmed the key role of piezoelectric effect for piezo-catalysis. The piezo-catalysis of sodium niobate nanowires provides a high-efficiency and reusable tool in application in depredating the dye wastewater. [ABSTRACT FROM AUTHOR]

Abstract In this work, an obvious enhancement of pyroelectrically-driven catalytic activity is found in BaTiO 3 @ZnO heterostructures synthesized hydrothermally and then calcined. The pure BaTiO 3 is able to decompose up to 45% of the RhB dye in aqueous solution (5 mg/L) under 30–54 °C cold-hot cycle. As the ZnO content coating on the surface of the BaTiO 3 nanofibers is increased from 0 to 5 wt%, the decomposition ratio of the BaTiO 3 @ZnO heterostructures for RhB dye in aqueous solution first increases and then decreases, giving a maximum value of 97% at 2.5 wt%. The kinetic rate constant (K = 0.06384 cycle−1) of the catalytic reaction for BaTiO 3 @2.5%ZnO is 4 times higher than that of pure BaTiO 3. The enhancement of catalytic activity of BaTiO 3 @ZnO may be due to the formation of a semiconductor junction in which the electric field effectively separating the pyro-induced electron-hole pairs and further accelerates carrier migration. The ferroelectric heterostructures of BaTiO 3 @ZnO show pyroelectrically-driven-catalysis and may hold potential for use in decomposing dye wastewater through harvesting cold-hot alternation thermal-energy. [ABSTRACT FROM AUTHOR]