팔라듐 나노 입자의 Sonochemical 환원
Palladium (Pd) is well known for its catalytic properties and is also widely used in materials research, electronics manufacturing, medicine, hydrogen purification, and various chemical applications. Using a sonochemical route, the size and morphology of palladium particles can be controlled by adjusting the PVP/Pd ratio. This enables the ultrasonic synthesis of either very fine, monodisperse nanoparticles or larger palladium aggregates, allowing particle dimensions to be tailored for optimal catalytic performance.
팔라듐 나노 입자의 초음파 생산
Ultrasonic palladium nanoparticle reduction offers a fast, reagent-efficient route to Pd(0) nanoparticles by using acoustic cavitation to generate localized high-energy conditions and reducing radicals in solution, enabling palladium ions to be reduced without conventional high-temperature processing.
A key advantage is process control: sonication time and stabilizer concentration, such as the PVP/Pd ratio, can influence whether the product forms as well-dispersed, rounded nanoparticles around 5 nm or as larger aggregates around 20 nm, which is industrially relevant because palladium performance in catalysis depends strongly on particle size, morphology, dispersion, and surface area. Since palladium nanoparticles are widely valuable as heterogeneous catalysts, electrocatalysts, and functional materials, ultrasonic reduction is attractive for producing finely dispersed Pd catalysts under comparatively mild liquid-phase conditions, with potential benefits for chemical synthesis, environmental catalysis, fuel-cell technologies, and other processes where high catalytic activity and efficient noble-metal utilization are economically important.
Industrial nanoparticle processing 초음파 처리기 UIP2000hdT로
Sample Preparation Procedure
샘플은 다음과 같이 준비되었습니다.
샘플의 경우 30mL의 EG와 5·10의 혼합물-6mol of PVP were preprared by magnetic stirring for 15 min. For the different samples, different amount of Pd(NO₃)₂ solution, 1.5mL and 2mL, were added. The sample mixtures were prepared with the ratio of 2·10-3mol Pd(NO₃)₂ in sample (a) and 2.66·10-3mol Pd(NO₃)₂ in sample (b). Both mixtures were sonicated in a 20mL vial using a probe-type ultrasonicator. Samples were taken after sonication times of 30, 60, 90, 120, 150, and 180 min.
실험 결과를 분석한 결과 다음과 같은 결과가 나타납니다.
- 1. Pd (II)를 Pd (0)로 초음파 화학적으로 환원시키는 것은 초음파 처리 시간에 따라 다릅니다.
- 2. 높은 PVP/Pd(II) 몰비는 둥근 모양과 약 5nm의 평균 직경을 갖는 단분산 팔라듐 입자의 형성으로 이어집니다.
- 3. 그러나 낮은 PVP/Pd(II) 몰비는 20nm를 중심으로 큰 크기 분포를 가진 응집체 팔라듐 나노입자를 얻는 것을 포함합니다.
팔라듐(II) 이온을 환원시키는 초음파 화학 경로 PD(II) 팔라듐 원자에 pd(0) 다음과 같이 가정할 수 있습니다.
- (1) Water pyrolysis: H₂O → •OH+•H
- (2) Radical formation: RH (Reducing agent) + •OH(•H) → •R + H₂O(H₂)
- (3) 이온 환원 : Pd (II) + 환원 라디칼 (•H, •R) → Pd (0) + R • CHO + H +
- (4) 입자 형성 : NPd(0) → Pdn
결과: PVP/Pd(II) 비율에 따라 분산 또는 집계된 PdN 를 얻었다.
Sonochemical reduction of Palladium: sample a (left) contains a high amount of PVP, sample b (right) a low amount of PVP. Sonication time with UP100H: 180 min. Sample a shows mono dispersed Pd nano particles, sample b aggregated Pd nano particles.
Images and study: ©Nemamcha and Rehspringer, 2008
분석 및 결과
UV 가시 흡수 분석은 팔라듐 (II) 이온에서 팔라듐 (0) 원자로의 초음파 화학적 환원과 초음파장에서의 머무름 시간 사이의 관계를 확인합니다. 팔라듐 (II) 이온이 팔라듐 (0) 원자로 환원되는 과정이 진행되며 초음파 처리 시간이 증가함에 따라 완전히 달성 될 수 있습니다. 투과 전자 현미경(TEM)의 현미경 사진은 다음을 보여줍니다.
- When a high amount of PVP is added, the sonochemical reduction of palladium ions leads to the formation of monodispersed palladium particles with spherical shape and a mean diameter of approx. 5nm.
- The use of a small quantity of PVP involves the obtaining of aggregates palladium nanoparticles. The dynamic light scattering (DLS) measurements reveal that the palladium nanoparticles aggregates have a large size distribution centered at 20nm.
The lab sonicator UP100H has been used for the preparation of palladium nano-particles.
팔라듐 (Pd) 나노 입자는 초음파 처리로 제조 할 수 있습니다
설계, 제조 및 컨설팅 – 독일에서 만든 품질
Hielscher 초음파는 최고의 품질과 디자인 표준으로 잘 알려져 있습니다. 견고 함과 쉬운 작동으로 초음파를 산업 시설에 원활하게 통합 할 수 있습니다. 거친 조건과 까다로운 환경은 Hielscher 초음파기로 쉽게 처리 할 수 있습니다.
Hielscher 초음파는 ISO 인증 회사이며 최첨단 기술과 사용자 친화성을 갖춘 고성능 초음파에 특히 중점을 둡니다. 물론, Hielscher 초음파는 CE를 준수하며 UL, CSA 및 RoHs의 요구 사항을 충족합니다.
문헌/참고문헌
- Nemamcha, A.; Rehspringer, J. L. (2008): Morphology of dispersed and aggregated PVV-Pd nanoparticles prepared by ultrasonic irradiation of Pd(NO₃)₂ solution in ethylene glycol. Rev. Adv. Mater. Sci. 18;2008. 685-688.
- Prekob, Á., Muránszky, G., Kocserha, I. et al. (2020): Sonochemical Deposition of Palladium Nanoparticles Onto the Surface of N-Doped Carbon Nanotubes: A Simplified One-Step Catalyst Production Method. Catalysis Letters 150, 2020. 505–513.
- Haitao Zheng, Mphoma S. Matseke, Tshimangadzo S. Munonde (2019): The unique Pd@Pt/C core-shell nanoparticles as methanol-tolerant catalysts using sonochemical synthesis. Ultrasonics Sonochemistry, Volume 57, 2019. 166-171.
알아 둘 만한 가치가 있는 사실
What is Palladium?
Palladium is a rare, silvery-white precious metal with the chemical symbol Pd and atomic number 46. It belongs to the platinum-group metals and is valued because it is chemically stable, conducts electricity, absorbs hydrogen, and acts as an excellent catalyst. Finely divided palladium is especially effective for hydrogenation and dehydrogenation reactions, and heated palladium can allow hydrogen to diffuse through it, which makes it useful for hydrogen separation and purification.
What are Palladium Nanoparticles Used for?
Palladium nanoparticles are used mainly as high-surface-area catalysts. Because nanoparticles expose far more active surface area than bulk palladium, they can improve catalyst efficiency and reduce the amount of expensive noble metal required. Typical applications include chemical synthesis, hydrogenation reactions, carbon–carbon coupling reactions, electrocatalysis, fuel-cell research, hydrogen sensing and storage, environmental catalysis, and some biomedical research areas such as antimicrobial, photothermal, and anticancer systems. Palladium catalytic behavior depends strongly on particle size, morphology, and dispersion.
Palladium nanoparticles are also used to dope other particles in order to achieve catalytic functionalities. Read more about the ultrasonic pathway to synthesize Pd/N-BCNT as Fischer-Tropsch catalyst!
Is Palladium Toxic?
Elemental metallic palladium is generally considered to have low toxicity and no known biological role, but palladium compounds, salts, dusts, and nanoscale forms should be handled carefully. Occupational or laboratory exposure can cause irritation or sensitization depending on the compound and route of exposure, and palladium chloride solutions, for example, may irritate mucous membranes. For industrial handling, the practical answer is: bulk metallic palladium is relatively low-risk, but palladium powders, soluble palladium salts, and palladium nanoparticles should be treated as potentially hazardous materials, with dust control, ventilation, gloves, eye protection, and proper waste handling.