Recent Progress in Biochar-Based Photocatalysts for Wastewater Treatment: Synthesis, Mechanisms, and Applications

Biochar (BC) is a carbon-rich material produced from pyrolysis of biomass. In addition to its low toxicity, environmental compatibility, and low cost, BC has the desired advantages of well-developed mesoporous structure and abundant surface functional groups. In recent years, BC-based photocatalysts (BCPs) have played a significant role in many environmental fields. In this paper, we highlight the current progress and several exciting results of BCPs by focusing on their synthesis, characterization, mechanisms, and applications in wastewater treatment. Details on various preparation methods include sol–gel, hydrothermal/solvothermal, ultrasound, calcination, and in situ methods are summarized and discussed. The underlying mechanisms and the applications of BCPs for different semiconductors are reviewed. Furthermore, some future trends and potentials are outlined.

Download Full-text

A simple approach to prepare fluorescent molecularly imprinted nanoparticles

RSC Advances ◽

10.1039/d0ra10618f ◽

2021 ◽

Vol 11 (13) ◽

pp. 7732-7737

Author(s):

Fenying Wang ◽

Dan Wang ◽

Tingting Wang ◽

Yu Jin ◽

Baoping Ling ◽

...

Keyword(s):

High Performance ◽

Low Cost ◽

Sol Gel ◽

Silica Sol ◽

Simple Approach ◽

Imprinted Polymer ◽

Molecularly Imprinted ◽

Low Toxicity ◽

Good Biocompatibility ◽

Molecularly Imprinted Nanoparticles

Fluorescent molecularly imprinted polymer (FMIP) gains great attention in many fields due to their low cost, good biocompatibility and low toxicity. Here, a high-performance FMIP was prepared based on the autocatalytic silica sol–gel reaction.

Download Full-text

The preparation of Li7La3Zn2O12(LLZO) battery ceramic and its conductivity

Journal of Physics Conference Series ◽

10.1088/1742-6596/2079/1/012017 ◽

2021 ◽

Vol 2079 (1) ◽

pp. 012017

Author(s):

Xiaoli Zhang ◽

Xiaoyi Zhang ◽

Yu Yang ◽

Jiawei Duan ◽

Liwei Mi

Keyword(s):

Solid Electrolytes ◽

Low Cost ◽

Sol Gel ◽

Complex Method ◽

Preparation Methods ◽

Liquid Sintering ◽

Field Assisted Sintering ◽

Sintering Method ◽

Fast Synthesis ◽

Combustion Technique

Abstract For Li7La3Zr2O12 (LLZO) solid electrolytes, higher density usually means higher ionic conductivity. Researchers tried many preparation methods to get high density samples and at same times to realize industrial production, low cost, scalable and fast synthesis techniques. In this paper, the mainstream preparation methods of LLZO was given, as polymerized complex method, sol-gel method, field assisted sintering, combustion technique, auto-consolidation method, water-based solvent method. Among these methods, the last four methods can always increase the density to more than 93%. Especially the field assisted sintering method can make the relative density to be high as 99.8%. And all of these methods can make the ion conductivity to be higher than 1.4 × 10-4 S cm-1. Also, most of these methods introduced the Al element into LLZO to realize the liquid sintering.

Download Full-text

Isotherm Studies of Malachite Green Removal by Yarn Processing Sludge-Based Activated Carbon

Chemistry-Didactics-Ecology-Metrology ◽

10.2478/cdem-2019-0011 ◽

2019 ◽

Vol 24 (1-2) ◽

pp. 127-134

Author(s):

Shu Hui Tang ◽

Muhammad Abbas Ahmad Zaini

Keyword(s):

Wastewater Treatment ◽

Activated Carbon ◽

Low Cost ◽

Industrial Applications ◽

Koh Activation ◽

Treatment Technique ◽

Dye Wastewater ◽

High Carbon Content ◽

Preparation Methods ◽

Operation Cost

Abstract Adsorption is an effective wastewater treatment technique which has been widely used in various industrial applications. However, the high operation cost involving commercial activated carbon in industrial processes is the main drawback. Sewage sludge is an auspicious precursor of activated carbon owing to its high carbon content, rich functional groups, low cost, high availability and abundance. This research was aimed to establish the feasibility of converting yarn processing sludge into activated carbon by KI + KOH activation and char at 700 °C for 1 h. The effect of preparation strategies on the properties of sludge-based adsorbents (SBA) was reviewed. The applications of SBAs in the removal of dyes and model pollutants were discussed. The results from this study proved that the preparation of yarn processing sludge-based activated carbon via KI + KOH activation is feasible and effective in the adsorption of dye. This paper provides further insight on the preparation methods of sludge-based adsorbents and dye wastewater treatment using these adsorbents.

Download Full-text

ZnO Nanostructures and Electrospun ZnO–Polymeric Hybrid Nanomaterials in Biomedical, Health, and Sustainability Applications

Nanomaterials ◽

10.3390/nano9101449 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1449 ◽

Cited By ~ 7

Author(s):

Eloisa Ferrone ◽

Rodolfo Araneo ◽

Andrea Notargiacomo ◽

Marialilia Pea ◽

Antonio Rinaldi

Keyword(s):

Biomedical Applications ◽

Low Cost ◽

Antibacterial Properties ◽

Specific Cell ◽

Zno Nanostructures ◽

Bibliographic Data ◽

Recent Developments ◽

Fresh Perspective ◽

Low Toxicity ◽

Underlying Mechanisms

ZnO-based nanomaterials are a subject of increasing interest within current research, because of their multifunctional properties, such as piezoelectricity, semi-conductivity, ultraviolet absorption, optical transparency, and photoluminescence, as well as their low toxicity, biodegradability, low cost, and versatility in achieving diverse shapes. Among the numerous fields of application, the use of nanostructured ZnO is increasingly widespread also in the biomedical and healthcare sectors, thanks to its antiseptic and antibacterial properties, role as a promoter in tissue regeneration, selectivity for specific cell lines, and drug delivery function, as well as its electrochemical and optical properties, which make it a good candidate for biomedical applications. Because of its growing use, understanding the toxicity of ZnO nanomaterials and their interaction with biological systems is crucial for manufacturing relevant engineering materials. In the last few years, ZnO nanostructures were also used to functionalize polymer matrices to produce hybrid composite materials with new properties. Among the numerous manufacturing methods, electrospinning is becoming a mainstream technique for the production of scaffolds and mats made of polymeric and metal-oxide nanofibers. In this review, we focus on toxicological aspects and recent developments in the use of ZnO-based nanomaterials for biomedical, healthcare, and sustainability applications, either alone or loaded inside polymeric matrices to make electrospun composite nanomaterials. Bibliographic data were compared and analyzed with the aim of giving homogeneity to the results and highlighting reference trends useful for obtaining a fresh perspective about the toxicity of ZnO nanostructures and their underlying mechanisms for the materials and engineering community.

Download Full-text

Comparision of the Preparation Methods of Mesoporous Phosphate Compounds Belonging to NZP Family

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.631-632.116 ◽

2013 ◽

Vol 631-632 ◽

pp. 116-120

Author(s):

Peng Zheng ◽

Lin Hua Zhu ◽

Tian Si ◽

Yan Lin Sun

Keyword(s):

Pore Diameter ◽

Sol Gel ◽

Mesoporous Structure ◽

Powder Materials ◽

X Ray Diffraction ◽

Average Pore ◽

Preparation Methods ◽

X Ray ◽

Low Thermal Expansion ◽

Adsorption Desorption

Using polyethylene oxide (PEO) as template, the new types of mesoporous phosphate compound which belongs to NaZr2(PO4)3(NZP) family were synthesized by copreciptate, sol-gel and mechanochemical activation(MA) route respectively. The physical phase and pore structure of the synthesized powder materials were characterized by X-ray diffraction (XRD) and N2 adsorption–desorption. The results showed that the crystalline NZP family compound with mesoporous structure is formed by sol-gel route followed with calcination as well as MA method followed with hydrothermal treatment when the mole ratio of PEO to Zr is 1:10, and the specific surface area, average pore diameter and pore volume of the synthesized powder is 20-50m2/g, 3-6.nm and 0.05-0.12cm3/g respectively. The above research results indicate that it is promising to expand the application field of the powder of NZP family from low thermal expansion ceramics to catalytic materials.

Download Full-text

Nano Phytomedicine Based Delivery System for CNS Disease

Current Drug Metabolism ◽

10.2174/1389200221666200523161003 ◽

2020 ◽

Vol 21 (9) ◽

pp. 661-673 ◽

Cited By ~ 1

Author(s):

Mohammed Asadullah Jahangir ◽

Chettupalli Anand ◽

Abdul Muheem ◽

Sadaf Jamal Gilani ◽

Mohamad Taleuzzaman ◽

...

Keyword(s):

Herbal Medicine ◽

Low Cost ◽

Herbal Medicines ◽

Herbal Drugs ◽

Widespread Acceptance ◽

The Central Nervous System ◽

Low Toxicity ◽

Ancient Times ◽

Plant Sources ◽

Herbal Formulations

Herbal medicines are being used since ancient times and are an important part of the alternative and traditional medicinal system. In recent decades, scientists are embracing herbal medicines based on the fact that a number of drugs that are currently in use are derived directly or indirectly from plant sources. Moreover, herbal drugs have lesser side effects, albeit are potentially strong therapeutic agents. The herbal medicine market is estimated to be around US $62 billion globally. Herbal medicine has gained widespread acceptance due to its low toxicity, low cost, ease of accessibility and efficacy in treating difficult diseases. Safety and efficacy are another important factors in the commercialization process of herbal medicines. Nanotechnology has been shown to be potentially effective in improving the bioactivity and bioavailability of herbal medicines. Development of nano-phytomedicines (or by reducing the size of phytomedicine), attaching polymers with phytomedicines and modifying the surface properties of herbal drugs, have increased the solubility, permeability and eventually the bioavailability of herbal formulations. Novel formulations such as niosomes, liposomes, nanospheres, phytosomes etc., can be exploited in this area. This article reviews herbal medicines, which have prominent activity in the Central Nervous System (CNS) disorders and reported nano-phytomedicines based delivery systems.

Download Full-text

Synthesis and characterization of Mg–Zn ferrite based flexible microwave composites and its application as SNG metamaterial

Scientific Reports ◽

10.1038/s41598-021-87100-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Md Atiqur Rahman ◽

Mohammad Tariqul Islam ◽

Mandeep Singh Jit Singh ◽

Md Samsuzzaman ◽

Muhammad E. H. Chowdhury

Keyword(s):

Low Cost ◽

Sol Gel ◽

Microwave Frequency ◽

Dielectric Substrate ◽

Dielectric Constants ◽

Potential Candidate ◽

Flexible Composites ◽

Average Grain Size ◽

Zn Ferrite ◽

High Flexibility

AbstractIn this article, we propose SNG (single negative) metamaterial fabricated on Mg–Zn ferrite-based flexible microwave composites. Firstly, the flexible composites are synthesized by the sol-gel method having four different molecular compositions of MgxZn(1−x)Fe2O4, which are denoted as Mg20, Mg40, Mg60, and Mg80. The structural, morphological, and microwave properties of the synthesized flexible composites are analyzed using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and conventional dielectric assessment kit (DAK) to justify their possible application as dielectric substrate at microwave frequency regime. Thus the average grain size is found from 20 to 24 nm, and the dielectric constants are 6.01, 5.10, 4.19, and 3.28, as well as loss tangents, are 0.002, 0.004, 0.006, and 0.008 for the prepared Mg–Zn ferrites, i.e., Mg20, Mg40, Mg60, and Mg80 respectively. Besides, the prepared low-cost Mg–Zn ferrite composites exhibit high flexibility and lightweight, which makes them a potential candidate as a metamaterial substrate. Furthermore, a single negative (SNG) metamaterial unit cell is fabricated on the prepared, flexible microwave composites, and their essential electromagnetic behaviors are observed. Very good effective medium ratios (EMR) vales are obtained from 14.65 to 18.47, which ensure the compactness of the fabricated prototypes with a physical dimension of 8 × 6.5 mm2. Also, the proposed materials have shown better performances comparing with conventional FR4 and RO4533 materials, and they have covered S-, C-, X-, Ku-, and K-band of microwave frequency region. Thus, the prepared, flexible SNG metamaterials on MgxZn(1−x)Fe2O4 composites are suitable for microwave and flexible technologies.

Download Full-text

The Role of Biochar in Regulating the Carbon, Phosphorus, and Nitrogen Cycles Exemplified by Soil Systems

Sustainability ◽

10.3390/su13105612 ◽

2021 ◽

Vol 13 (10) ◽

pp. 5612

Author(s):

Shu-Yuan Pan ◽

Cheng-Di Dong ◽

Jenn-Feng Su ◽

Po-Yen Wang ◽

Chiu-Wen Chen ◽

...

Keyword(s):

Environmental Sustainability ◽

Soil Amendment ◽

Environmental Control ◽

Current Knowledge ◽

Soil Environment ◽

Nitrogen And Phosphorus ◽

Soil Systems ◽

P Mineralization ◽

Rich Material ◽

Pyrolysis Of Biomass

Biochar is a carbon-rich material prepared from the pyrolysis of biomass under various conditions. Recently, biochar drew great attention due to its promising potential in climate change mitigation, soil amendment, and environmental control. Obviously, biochar can be a beneficial soil amendment in several ways including preventing nutrients loss due to leaching, increasing N and P mineralization, and enabling the microbial mediation of N2O and CO2 emissions. However, there are also conflicting reports on biochar effects, such as water logging and weathering induced change of surface properties that ultimately affects microbial growth and soil fertility. Despite the voluminous reports on soil and biochar properties, few studies have systematically addressed the effects of biochar on the sequestration of carbon, nitrogen, and phosphorus in soils. Information on microbially-mediated transformation of carbon (C), nitrogen (N), and phosphorus (P) species in the soil environment remains relatively uncertain. A systematic documentation of how biochar influences the fate and transport of carbon, phosphorus, and nitrogen in soil is crucial to promoting biochar applications toward environmental sustainability. This report first provides an overview on the adsorption of carbon, phosphorus, and nitrogen species on biochar, particularly in soil systems. Then, the biochar-mediated transformation of organic species, and the transport of carbon, nitrogen, and phosphorus in soil systems are discussed. This review also reports on the weathering process of biochar and implications in the soil environment. Lastly, the current knowledge gaps and priority research directions for the biochar-amended systems in the future are assessed. This review focuses on literatures published in the past decade (2009–2021) on the adsorption, degradation, transport, weathering, and transformation of C, N, and P species in soil systems with respect to biochar applications.

Download Full-text

Performance Improvement of ZnSnO Thin-Film Transistors with Low-Temperature Self-Combustion Reaction

Electronics ◽

10.3390/electronics10091099 ◽

2021 ◽

Vol 10 (9) ◽

pp. 1099

Author(s):

Ye-Ji Han ◽

Se Hyeong Lee ◽

So-Young Bak ◽

Tae-Hee Han ◽

Sangwoo Kim ◽

...

Keyword(s):

Thin Film ◽

Photoelectron Spectroscopy ◽

Large Scale ◽

Low Cost ◽

Thermal Analyses ◽

Thin Film Transistor ◽

Sol Gel ◽

Annealing Temperatures ◽

Zinc Tin Oxide ◽

Thermal Limitation

Conventional sol-gel solutions have received significant attention in thin-film transistor (TFT) manufacturing because of their advantages such as simple processing, large-scale applicability, and low cost. However, conventional sol-gel processed zinc tin oxide (ZTO) TFTs have a thermal limitation in that they require high annealing temperatures of more than 500 °C, which are incompatible with most flexible plastic substrates. In this study, to overcome the thermal limitation of conventional sol-gel processed ZTO TFTs, we demonstrated a ZTO TFT that was fabricated at low annealing temperatures of 350 °C using self-combustion. The optimized device exhibited satisfactory performance, with μsat of 4.72 cm2/V∙s, Vth of −1.28 V, SS of 0.86 V/decade, and ION/OFF of 1.70 × 106 at a low annealing temperature of 350 °C for one hour. To compare a conventional sol-gel processed ZTO TFT with the optimized device, thermogravimetric and differential thermal analyses (TG-DTA) and X-ray photoelectron spectroscopy (XPS) were implemented.

Download Full-text