1
|
Effects of surface microtopography on material removal and ultra-smooth surface creation processes in ultraviolet-induced nanoparticle colloid jet machining. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
2
|
Song X, Wang X, Wang S, Liu S, Ge S. Experimental Study on Ultra-Precision Polishing of Ti-6Al-4V by Ultraviolet-Induced Nanoparticle Colloid Jet Machining. MATERIALS 2021; 14:ma14175014. [PMID: 34501103 PMCID: PMC8434296 DOI: 10.3390/ma14175014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 08/25/2021] [Accepted: 08/31/2021] [Indexed: 11/29/2022]
Abstract
Ti-6Al-4V is widely used in various fields of modern industry, but it is difficult to obtain an ultra-smooth surface of Ti-6Al-4V due to its poor machinability. In this article, ultraviolet-induced (UV-induced) nanoparticle colloid jet machining was utilized to carry out ultra-precision polishing of Ti-6Al-4V to improve the surface quality. The results of infrared differential spectroscopy before and after polishing show that new chemical bonds such as Ti-O-Ti (Al-O-Ti and V-O-Ti) appear on the Ti-6Al-4V workpiece surface, which indicates that the material of Ti-6Al-4V workpiece is removed through the chemical interaction between TiO2 nanoparticles and workpiece surface in the process of UV-induced nanoparticle colloid jet machining. The comparison of metallographic structure of Ti-6Al-4V before and after polishing shows that the chemical activity and material removal rate of the primary α phase in Ti-6Al-4V is higher than that of the remnant β phase in UV-induced nanoparticle colloid jet machining, which lead to the well-distributed nano-scale surface peaks and valleys at regular intervals on the polished Ti-6Al-4V workpiece surface. After polishing, the longitudinal residual stress on the surface of Ti-6Al-4V workpiece decreases from 75 MPa to 67 MPa and the transverse stress decreases from 13 MPa to 3 MPa. The surface roughness of Ti-6Al-4V workpiece is reduced from Sa 76.7 nm to Sa 2.87 nm by UV-induced nanoparticle colloid jet machining.
Collapse
|
3
|
Facile Synthesis of Flower-Like TiO2-Based Composite for Adsorption–Photocatalytic Degradation of High-Chroma Methylene Blue. Catalysts 2021. [DOI: 10.3390/catal11040515] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A flower-like TiO2-based composite (denoted as Zn-Ti-6) was prepared using a flower-like zinc oxide template for adsorption–photocatalytic degradation of high-chroma methylene blue. The reaction took place in an alkaline environment following hydrochloric acid treatment to remove the template and form TiO2-based composite. Sodium hydroxide played both roles of morphology-directing agent and reactive etchant. The possible mechanism for the formation of flower-like Zn-Ti-6 was proposed. The adsorption and photocatalytic degradation behavior of Zn-Ti-6 on methylene blue (MB) removal was also investigated. The results revealed that Zn-Ti-6 showed better adsorption and photocatalytic degradation performance than TiO2 nanoparticles owing to its much larger specific surface area, more abundant hydroxyls, and lower photoluminescence intensity. The adsorption and photocatalytic degradation data of Zn-Ti-6 were well fitted to the pseudo-second-order and pseudo-first-order kinetics models, respectively. The excellent adsorption performance of Zn-Ti-6 is largely beneficial to the subsequent photocatalytic degradation performance for high-chroma wastewater treatment. Overall, this study contributes a facile fabrication strategy for flower-like TiO2-based composite to achieve the adsorption–photocatalytic degradation of high-chroma wastewater.
Collapse
|
4
|
Experimental Investigation on the Effects of Photocatalysis in Ultraviolet-Induced Nanoparticle Colloid Jet Machining. MATERIALS 2021; 14:ma14051070. [PMID: 33669047 PMCID: PMC7956710 DOI: 10.3390/ma14051070] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 02/16/2021] [Accepted: 02/22/2021] [Indexed: 11/17/2022]
Abstract
In this paper, ultraviolet (UV)-induced nanoparticle colloid jet machining is proposed to achieve ultrasmooth surface polishing by using the interaction between nanoparticles and the workpiece surface under the action of the ultraviolet field and the hydrodynamic pressure field. In the process of UV-induced nanoparticle colloid jet machining, the effects of photocatalysis on the interaction between nanoparticles and the workpiece surface need to be further studied in order to better understand the polishing process. This paper presents the interaction between TiO2 nanoparticles and a Si workpiece surface with and without ultraviolet irradiation. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) were applied to investigate the differences in the interaction of TiO2 nanoparticles with Si workpieces. The SEM and XPS results indicate that the photocatalysis of UV light can promote the interaction between TiO2 nanoparticles and a Si surface by creating more interfacial reaction active centers between the TiO2 nanoparticles and the Si workpiece. The FT-IR and XPS spectra show that TiO2 nanoparticles are chemically bonded to the Si workpiece by oxygen-bridging atoms in Ti-O-Si bonds. Due to the effects of photocatalysis, UV-induced nanoparticle colloid jet machining has a higher polishing efficiency than nanoparticle colloid jet machining with the same polishing parameters.
Collapse
|
5
|
Song X, Gao G. Removal Mechanism Investigation of Ultraviolet Induced Nanoparticle Colloid Jet Machining. Molecules 2020; 26:molecules26010068. [PMID: 33375638 PMCID: PMC7794891 DOI: 10.3390/molecules26010068] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 11/16/2022] Open
Abstract
Ultraviolet induced nanoparticle colloid jet machining is a new ultra-precision machining technology utilizing the reaction between nanoparticles and the surface of the workpiece to achieve sub-nanometer ultra-smooth surface manufacturing without damage. First-principles calculations based on the density functional theory (DFT) were carried out to study the atomic material removal mechanism of nanoparticle colloid jet machining and a series of impacting and polishing experiments were conducted to verify the mechanism. New chemical bonds of Ti-O-Si were generated through the chemical adsorption between the surface adsorbed hydroxyl groups of the TiO2 cluster and the Si surface with the adsorption energy of at least -4.360 eV. The two Si-Si back bonds were broken preferentially and the Si atom was removed in the separation process of TiO2 cluster from the Si surface realizing the atomic material removal. A layer of adsorbed TiO2 nanoparticles was detected on the Si surface after 3 min of fixed-point injection of an ultraviolet induced nanoparticle colloid jet. X-ray photoelectron spectroscopy results indicated that Ti-O-Si bonds were formed between TiO2 nanoparticles and Si surface corresponding to the calculation result. An ultra-smooth Si workpiece with a roughness of Rq 0.791 nm was obtained by ultraviolet induced nanoparticle colloid jet machining.
Collapse
Affiliation(s)
- Xiaozong Song
- School of Mechanical and Electronical Engineering, Lanzhou University of Technology, Lanzhou 730050, China
- Correspondence: ; Tel.: +86-0931-2973860
| | - Gui Gao
- State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China;
| |
Collapse
|
6
|
Parrino F, De Pasquale C, Palmisano L. Influence of Surface-Related Phenomena on Mechanism, Selectivity, and Conversion of TiO 2 -Induced Photocatalytic Reactions. CHEMSUSCHEM 2019; 12:589-602. [PMID: 30387918 DOI: 10.1002/cssc.201801898] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2018] [Revised: 09/28/2018] [Indexed: 06/08/2023]
Abstract
Heterogeneous photocatalysis is the result of an inextricable connection of several factors differently contributing to the overall process. Photon absorption is the "sine qua non" condition for the reaction to occur. In fact, photons can be considered as immaterial reactants, and all of the phenomena related to the interaction of light-matter play a prominent role. However, other factors contribute in a concerted way to address the reaction, so that the relative contribution of each of them is often difficult to evaluate. In this framework, the present paper highlights some aspects of the interaction of TiO2 surface-adsorbate species that could be underestimated and their influence on the conversion, selectivity, and mechanisms of photocatalytic reactions. To this aim, some paradigmatic examples on the adsorption of water and organics on TiO2 are reported.
Collapse
Affiliation(s)
- Francesco Parrino
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, viale delle Scienze 8, 90128, Palermo, Italy
- Dipartimento di Energia, Ingegneria dell'informazione e Modelli Matematici (DEIM), Università degli Studi di Palermo, viale delle Scienze Ed. 6, 90128, Palermo, Italy
- Dipartimento di Ingegneria Industriale (DII), Università di Trento, via Sommarive 9, 38123, Trento, Italy
| | - Claudio De Pasquale
- Dipartimento di Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, viale delle Scienze 8, 90128, Palermo, Italy
| | - Leonardo Palmisano
- Dipartimento di Energia, Ingegneria dell'informazione e Modelli Matematici (DEIM), Università degli Studi di Palermo, viale delle Scienze Ed. 6, 90128, Palermo, Italy
| |
Collapse
|
7
|
Marcelino RBP, Amorim CC. Towards visible-light photocatalysis for environmental applications: band-gap engineering versus photons absorption-a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:4155-4170. [PMID: 30238261 DOI: 10.1007/s11356-018-3117-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Accepted: 08/31/2018] [Indexed: 06/08/2023]
Abstract
A range of different studies has been performed in order to design and develop photocatalysts that work efficiently under visible (and near-infrared) irradiation as well as to improve photons absorption with improved reactor design. While there is consensus on the importance of photocatalysis for environmental applications and the necessity to utilized solar irradiation (or visible-light) as driving force for these processes, it is not yet clear how to get there. Discussion on the future steps towards visible-light photocatalysis for environmental application is of great interest to scientific and industrial communities and the present paper reviews and discusses the two main approaches, band-gap engineering for efficient solar-activated catalysts and reactor designs for improved photons absorption. Common misconceptions and drawbacks of each technology are also examined together with insights for future progress.
Collapse
Affiliation(s)
- Rafaela B P Marcelino
- Research Group on Environmental Applications of Advanced Oxidation Processes, Graduate Program in Sanitation, Environment and Water Resources, School of Engineering, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, Brazil
| | - Camila C Amorim
- Research Group on Environmental Applications of Advanced Oxidation Processes, Graduate Program in Sanitation, Environment and Water Resources, School of Engineering, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, 31270-901, Belo Horizonte, Brazil.
| |
Collapse
|
8
|
Parrino F, Loddo V, Augugliaro V, Camera-Roda G, Palmisano G, Palmisano L, Yurdakal S. Heterogeneous photocatalysis: guidelines on experimental setup, catalyst characterization, interpretation, and assessment of reactivity. CATALYSIS REVIEWS-SCIENCE AND ENGINEERING 2018. [DOI: 10.1080/01614940.2018.1546445] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Francesco Parrino
- “Schiavello-Grillone” Photocatalysis Group, Università degli Studi di Palermo, Palermo, Italy
| | - Vittorio Loddo
- “Schiavello-Grillone” Photocatalysis Group, Università degli Studi di Palermo, Palermo, Italy
| | - Vincenzo Augugliaro
- “Schiavello-Grillone” Photocatalysis Group, Università degli Studi di Palermo, Palermo, Italy
| | - Giovanni Camera-Roda
- Dipartimento di Ingegneria Civile, Chimica, Ambientale e dei Materiali, Università di Bologna, Bologna, Italy
| | - Giovanni Palmisano
- Department of Chemical Engineering, Khalifa University of Science and Technology, Masdar City, United Arab Emirates
| | - Leonardo Palmisano
- “Schiavello-Grillone” Photocatalysis Group, Università degli Studi di Palermo, Palermo, Italy
| | - Sedat Yurdakal
- Kimya Bölümü, Fen-Edebiyat Fakültesi, Afyon Kocatepe Üniversitesi, Afyonkarahisar, Turkey
| |
Collapse
|
9
|
Muñoz-Batista MJ, Kubacka A, Fernández-García M. Effective Enhancement of TiO2 Photocatalysis by Synergistic Interaction of Surface Species: From Promoters to Co-catalysts. ACS Catal 2014. [DOI: 10.1021/cs501408u] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
| | - Anna Kubacka
- Instituto de Catálisis y Petroleoquı́mica,
CSIC, Marie Curie 2, 28049 Madrid, Spain
| | | |
Collapse
|