This work describes the facile synthesis of silver nanoparticle-decorated zinc oxide nanocomposite through a simple glycol reduction method. The silver nanoparticle-decorated zinc oxide nanocomposite-based pencil graphite electrode has been validated as a perceptive electrochemical sensing podium towards nitrite. The morphology of the prepared nanocomposite has been characterized via specific spectroscopic and electrochemical techniques. The sensor exhibits a notable enhancement in the cyclic voltammetric response to nitrite oxidation at an ideal peak potential of 0.76 V in pH 6.0 acetate buffer. Under optimum conditions of nitrite directly expanded with their concentration in the range from 30 to 1400 μM with a detection limit of 14 μM.

Herein, a series of g-C3N4 modified Bi2MoO6 nanocomposites using Bi2MoO6 and melamine as original materials are fabricated via sintering process. For presynthesis of Bi2MoO6 an ultrasonic-assisted hydrothermal technique is researched. The structure and composition of the nanocomposites are characterized by Raman spectroscopy, X-ray diffraction (XRD), and high-resolution field emission scanning electron microscopy (SEM). The improved photoelectrochemical properties are studied by photocurrent density, EIS, and amperometric i-t curve analysis. It is found that the structure of Bi2MoO6 nanoparticles remains intact, with good dispersion status. The as-prepared g-C3N4/Bi2MoO6 nanocomposites (BMC 5-9) are selected and investigated by SEM analysis, which inhibits special morphology consisting of Bi2MoO6 nanoparticles and some g-C3N4 nanosheets. The introduction of small sized g-C3N4 nanosheets in sample BMC 9 is effective to improve the charge separation and transfer efficiency, resulting in enhancing of the photoelectric behavior of Bi2MoO6. The improved photoelectronic behavior of g-C3N4/Bi2MoO6 may be attributed to enhanced charge separation efficiency, photocurrent stability, and fast electron transport pathways for some energy applications.

In recent years, special attention of energy researchers has been paid to application of polymer–carbon dots composite in energy storage systems. In this work, for the first time, we introduced a combination of polyaniline, carbon dots, polypyrrole and graphene as high performance supercapacitor. Synergistic effect of conductive polymers combined with specific properties of graphene and carbon dots improved the electrochemical performance of supercapacitor. Carbon dots was prepared from carrot juice hydrothermally as a biomass carbon source and polyaniline–carbon dots was synthesized via in-situ polymerization. Electrochemical performance of polyaniline with different carbon dots content was investigated and nanocomposite of polyaniline with 10 wt% carbon dots was selected to mix with polypyrrole–graphene to obtain a high potential window supercapacitor. The as-prepared composite was characterized by several spectroscopic and microscopic techniques. The electrochemical properties of this electrode were studied by cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy techniques. A polyaniline–carbon dots (10%)/polypyrrole–graphene has showed the maximum specific capacitance of 396 F g− 1. Value of specific capacity remained at 62% under the current density of 5 A g− 1.

Here, Zn ferrite is synthesized along with reduced graphene oxide (rGO) by a facile one-step hydrothermal method. The difference between the synthesized nanocomposites with those in other reported work is that the reaction conditions in this work are 160 oC for 12 h. The synthesized products are characterized by field-emission scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and attenuated total reflection. Further, the adsorption property of rGO–Zn ferrite (rGZF) nanocomposite is studied after confirming its successful synthesis. The adsorption capacity of rGZFs toward rhodamine B (RB) is ˃ 9.3 mg/g, whereas that of bare ZF nanoparticles is 1.8 mg/g in aqueous media. The efficiencies of rGZF and bare ZF to remove RB are 99 % and 20 %, respectively. Employing rGZF, 60 % of RB is decomposed within 5 min. The kinetic study reveals that the adsorption process of removing RB by bare Zn ferrite follows pseudo-firstorder kinetics. However, after zinc ferrite is incorporated with rGO, the kinetics changes to pseudo-second-order. Furthermore, the Langmuir isotherm is accomplished by the adsorption process employing rGZF, indicating that a monolayer adsorption process occurs. The thermodynamic parameters of the process are also calculated.

나노여과를위한 박막 나노복합체(TFN) 멤브레인 기술의 발전은 천연 자원에서 오염 물질을 제거하는 데 중요하 다. 최근에는 기존의 박막 복합체(TFC) 및 나노복합체 멤브레인에서 불가피한 단점을 극복하기 위해 다양한 금속유기구조체 (MOF) 수정이 테스트되었다. 일반적으로 MIL-101(Cr), UiO-66, ZIF-8 및 HKUST-1 [Cu3(BCT2)]은 용매 투과성 및 용질 제 거 측면에서 막 성능을 현저하게 향상시키는 것으로 입증되었다. 이 리뷰에서는 이러한 MOF가 나노 여과에 미치는 영향에 대 한 최근 연구가 논의될 것이다. 서로 다른 금속유기구조체의 동시 사용 및 고유한 금속유기구조체 레이어링 기술(예: 딥 코팅, 스프레이 사전 배치, Langmuir-Schaefer 필름 등)과 같은 다른 새로운 기능도 멤브레인 성능을 향상시켰다. 이러한 MOF 변 형 TFN 멤브레인은 각각의 TFC 및 TFN 멤브레인에서 분리 성능을 향상시키는 것으로 자주 나타났을 뿐만 아니라 많은 보 고서에서 비용 효율적이고 환경 친화적인 공정에 대한 잠재력을 설명한다.

A facile microwave assisted solvothermal process is designed for fabricating SnS nanoparticles decorated on graphene nanosheet, which used as visible light driven photocatalyst. Some typical characterization techniques such as XRD, FT-IR, SEM with EDX analysis, and TEM and BET analysis are used to analyse the physical characteristics of as-prepared samples. Spherical SnS nanoparticles are uniformly dispersed on the surface of graphene nanosheet due to ammonia, which can prevent the aggregation of graphene oxide. Meanwhile, microwave radiation provides fast energy that promotes the formation of spherical SnS nanoparticles within a short time. The visible light photocatalytic activity of as-prepared SnS-GR nanocomposites is analysed through photodegradation efficiency of methylene blue with high concentration. According to the higher photocatalytic property, the as-prepared SnS-GR nanocomposites can be expected to be an efficient visible light driven photocatalyst. After five cycles for decolorization, the rate decreases from 87 % to 78 % (about 9 %). It is obvious that the photocatalytic activity of SnS-GR nanocomposite has good repeatability.

Synergetic effect of multi-walled carbon nanotubes (MWCNTs)/nanoclays hybrid was investigated on the properties of highimpact polystyrene (HIPS) nanocomposite foams. The glass transition temperature and the cellular structure including the cell size and cell density were studied in details. Adding MWCNT and nanoclay increased the glass transition temperature of HIPS by 8.5 °C and 1.5 °C, respectively. The experimental results indicated that the cell size of HIPS foams was reduced from 84.05 to 60.97 μm and 40.22 μm using MWCNTs and nanoclays, respectively. The synergetic effect of MWCNT/nanoclay was more significant by reducing the cell size to 13.69 μm. The cell density was improved from 5.79 × 104 to 1.77 × 105 cell/ cm3 using MWCNTs and to 9.39 × 106 cell/cm3 using nanoclays. The cell density reached to 2.90 × 107 cell/cm3 using the synergetic effect of MWCNT/nanoclay.

수처리용 멤브레인의 기능 개선은 물과 에너지 자원 부족의 문제를 해결할 대표적인 과제로 떠오르고 있다. 나노 멤브레인을 활용한 정수 과정이 실용 가능할 수준에 도달하려면, 여과막의 표면에 박테리아나 미생물이 축적되는 생물 오손 (biofouling)을 해소하는 전략이 필수적으로 고안되어야 한다. 더 높은 내구성을 가지면서도 기본적인 목적인 여과에 대한 성 능 저하 없이 작동하는 수처리용 멤브레인을 합성하기 위해 현재 수많은 연구가 진행되고 있으며, 이러한 연구들에서 다루어 지는 전략들은 크게 두 가지 종류로 분류될 수 있다. 이 중 일반적으로 제시되는 유형은 멤브레인의 표면에 은 나노 입자를 고정하는 방식이다. 은 나노 입자를 활용하는 방법에도, 은 나노 입자가 오염 방지의 역할을 효과적으로 수행하는 데 필요한 표면과의 유의미한 결합을 실현하기 위해 여러 가지 세부 전략들이 제안되어진다. 은 나노 입자를 사용하는 방식에서 단점이 나 독성 유발 가능성 등의 위험성이 제기되면서, 은 외에도 구리, 그래핀 또는 아연 산화물, 아민 부분과 같은 물질의 입자들 을 적용하여 멤브레인을 알맞게 기능화 하는 유형의 연구들 또한 진행되었다. 위 두 가지 유형의 전략들을 주제로 한 연구들 은 여러 번의 시도와 실험을 거쳐 합성된 멤브레인의 표면에서 박테리아의 박멸이나 그의 번식을 예방하는 등의 몇 가지 주 목할 만한 성과를 낳았으며, 향후 추가적인 연구가 필요한 점들을 제시하였다. 본 리뷰논문은 금속 나노 입자 및 기타 물질들 이 수처리용 멤브레인의 표면과 결합하여 그의 방오화 특성에 기인하는 영향을 조사한 연구들에 대하여 다루고 있다.

The emergence of green methods for the synthesis of graphene-based composites became the gateway for the solution of pollution and economic synthetic methods. Herein, we reported a single step in situ synthesis of reduced graphene oxide sheets decorated with silver nanoparticles (CRG–Ag nanocomposite) using custard apple leaf extract as an effective reducing and stabilizing agent. The ultraviolet–visible, Fourier transform infrared and Raman techniques revealed a primary confirmation about the formation of the said nanocomposite. The X-ray diffraction studies confirmed the face-centred cubic crystal structure of silver nanoparticles (Ag NPs) of 30 nm in size. The high-resolution scanning electron microscope spectra revealed the uniform distribution of Ag NPs on the graphene sheets. This simple, novel and rapid approach enabled a facile production of homogeneously deposited Ag NPs on graphene sheets. Thus synthesized CRG–Ag nanocomposite showed excellent photocatalytic efficiency of 96% in 2 h under sunlight using methylene blue as a model pollutant.

정공 수송 층 (HTL)은 PSC의 효율 및 안정성을 증가시키기 위해 페로브스카이트 태양 전지 (PSC)에서 중요한 역할을 한다. 본 연구에서, 우리는 PSCs에서 HTL 스핀 코팅 및 블레이드 코팅 방법으로 니켈 산화물 구리 산화물 (NiO-CuO) 나노 입자 (NPs) 박막을 준비하였다. 스핀 코팅 및 블레이드 코팅 된 NiO-CuO 필름의 필름 특성은 원자력 현미경 (AFM)을 사용하여 조사하었고, 장치 성능에 대한 효과는 J-V 특성, 양자 효율 및 광 강도의 Voc 의존성을 사용하여 조사하었다. 결과적으로, 스핀 코팅으로 15.28 % 효율, 블레이드 코팅으로 11.18 % 효율을 달성하였다.

A novel approach was presented for deposition of nickel–graphene nanocomposite coating on copper. Unlike conventional methods, graphene and graphene oxide nanosheets were not used. The basis of the method is to synthesize graphene oxide by oxidation of graphite anode during the electrochemical deposition process. The obtained graphene oxide sheets were reduced during the deposition in the cathode and co-formed with the nickel deposition in the coating. The pulsed ultrasonic force was applied during the deposition process. When the ultrasonic force stops, the deposition process begins. Scanning electron microscopy, Raman spectroscopy, atomic force microscopy, X-ray diffraction and X-ray photoelectron spectroscopy confirmed the presence of graphene nanosheets in the coating. The amount of graphene nanosheets increases up to a maximum of 14.8 wt% by increasing the time of applying ultrasonic force to 6 s. In addition, with the presence of graphene in the nickel coating, the wear rate dramatically decreased.