Materials and Interfaces

Size-Controlled Synthesis of Rhodium Nanocatalysts and Applications in Low-Temperature Hydroformylation

2025-01-23T17:27:20+08:00

Article

Size-Controlled Synthesis of Rhodium Nanocatalysts and Applications in Low-Temperature Hydroformylation

Andrew Lamkins ^1,2, Charles J. Ward ^1,2, Jeffrey T. Miller ³, Ziad Alsudairy ⁴, Xinle Li ⁴, Joseph Thuma ^1,2, Ruoyu Cui ^1,2, Xun Wu ^1,2, Levi M. Stanley ¹ and Wenyu Huang ^1,2,*

¹ Department of Chemistry, Iowa State University, Ames, IA 50010, USA

² Ames Laboratory, U.S. Department of Energy, Ames, IA 50010, USA

³ Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN 47907, USA

⁴ Department of Chemistry, Clark Atlanta University, Atlanta, GA 30314, USA

* Correspondence: whuang@iastate.edu

Received: 3 December 2024; Revised: 30 December 2024; Accepted: 3 January 2025; Published: 10 January 2025

Abstract: Controlling the size and distribution of metal nanoparticles is one of the simplest methods of tuning the catalytic properties of a material. For a nanocrystal particle, the ratio of edge-to-terrace sites can be critical in determining its catalytic activity and selectivity to desired products. To study these effects, we have developed a simple impregnation method of controlling the dispersion of rhodium atoms at the same metal loading in the range of nanoparticles less than 10 nm. Rh precursor salts are loaded onto inert SBA-15, and increasing the ratio of chloride to acetylacetonate salts improves the dispersion of rhodium atoms to form small Rh nanoparticles. Extensive characterization of the size-controlled catalysts, including XAS and in-situ CO-DRIFTS studies, has been performed to characterize the structure of Rh nanoparticles. Applying these catalysts to the hydroformylation of styrene, we observed that turnover frequency increases with decreasing particle size from 6.4 to 1.6 nm. When applied to hydroformylation reactions, we achieved a high branched product selectivity and successfully demonstrated a route to synthesizing the pain relief drug ibuprofen. This simple method can also synthesize Pt and Pd nanoparticles between 2–10 nm.

Constructing Co Cluster Sites for Selective CO₂ Hydrogenation via Phase Segregation from Co-Doped TiO₂ Nanocrystals

2025-01-23T17:27:17+08:00

Article

Constructing Co Cluster Sites for Selective CO₂ Hydrogenation via Phase Segregation from Co-Doped TiO₂ Nanocrystals

Xiangru Wei ¹, Yizhen Chen ¹, Yulu Zhang ¹, Liyue Zhang ¹, Lu Ma ², Matthew M. Yung ³ and Sen Zhang ^1,*

¹ Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA

² National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, NY 11973, USA

³ Bioenergy Science and Technology Directorate, National Renewable Energy Laboratory, Denver West Parkway,
Golden, CO 80401, USA

* Correspondence: sz3t@virginia.edu

Received: 7 November 2024; Revised: 2 January 2025; Accepted: 3 January 2025; Published: 23 January 2025

Abstract: This article presents a Co phase segregation strategy for creating stable Co cluster catalytic sites on TiO₂, enabling selective CO₂ hydrogenation to CO. Through oxidative calcination, pre-synthesized Co-doped brookite TiO₂ nanorods transform into a mixed TiO₂ phase, leading to the phase segregation of Co species. The resulting Co clusters, stabilized by strong Co-TiO₂ interactions during reductive CO₂ hydrogenation, effectively suppress the formation of larger nanoparticles. The undercoordinated sites of these clusters promote a high CO production rate with near-unit selectivity, contrasting with Co nanoparticles, which favor CH₄ formation under identical conditions. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) analysis indicates that the weakened CO adsorption on Co clusters is key to their enhanced CO selectivity, highlighting this method as a promising approach for efficient CO₂ utilization.

Intrinsically Multi-Color Device Based on Dynamic Cooperation of Molecular Switches and Metal Ions

2025-02-19T15:17:52+08:00

Article

Intrinsically Multi-Color Device Based on Dynamic Cooperation of Molecular Switches and Metal Ions

Min Li, Shuo Wang*, Ruipeng Shen, Yigui Xie, Yu-Mo Zhang and Sean Xiao-An Zhang*

State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun 130012, China.

* Correspondence: wangshuo@jlu.edu.cn (S.W.); seanzhang@jlu.edu.cn (S.X.-A.Z.)

Received: 6 January 2025; Revised: 5 February 2025; Accepted: 11 February 2025; Published: 19 February 2025

Abstract: Multi-color electrochromic material is a long-expected and extremely challenging material, which is important for electrochromic technology to be applied in adaptive camouflage, augmented reality, transparent display, etc. Here, an intrinsically multi-color indirect-electrochromic material based on supramolecular interactions of unusual multi-state molecular switch and metal ion was developed, combining the advantage of multi-state of molecular switch and chemical stability of metal ion. Related prototype device, with transparent intrinsic colorless, magenta, cyan and various mixed colors, have been explored and demonstrated. The mechanism was based on the dynamic coordination of multiple metal ions and single-molecular-dual-switches within fragile supramolecular clusters. Wherein, the color and lightness could be controlled simply by the bias applied, with abilities such as transmittance change (41%), coloring time (7.8 s), coloration efficiency (>100 cm²/C), and reversibility (>600 test cycles, no abnormal changes). The prototype device was fabricated to show the potential to be used in low energy consumption display.

High-Yield, Environmentally-Friendly, and Sustainable Synthesis of Silver Nanowires Using Tannic Acid and Their Application in Conductive Ink Preparation: Economic Analysis and Rheological Investigation

2025-02-20T15:30:16+08:00

Article

High-Yield, Environmentally-Friendly, and Sustainable Synthesis of Silver Nanowires Using Tannic Acid and Their Application in Conductive Ink Preparation: Economic Analysis and Rheological Investigation

Sina Kaabipour ¹, Finley Neal ², and Shohreh Hemmati ^2,*

¹ School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078, USA

² School of Mathematics and Natural Sciences, The University of Southern Mississippi, Hattiesburg, MS 39406, USA

* Correspondence: shohreh.hemmati@usm.edu

Received: 25 November 2024; Revised: 15 January 2025; Accepted: 11 February 2025; Published: 20 February 2025

Abstract: Silver nanowires (AgNWs) have garnered significant attention during the past decade thanks to their applications in conductive inks used for electronic applications. The polyol process, widely used for AgNW synthesis, is known for its effectiveness in producing high aspect ratio and high yield nanowires. However, this process suffers from drawbacks such as high energy consumption and use of unsustainable reagents derived from nonrenewable resources, which makes its large-scale utilization and economic feasibility challenging. In contrast, green synthesis methods offer potential solutions by employing environmentally friendly and cost-effective approaches. In this study, we offer a high-yield (90%) approach for the inexpensive, environmentally friendly, and sustainable synthesis of AgNWs, and show that the production cost per gram of AgNWs can be reduced by 31.72% compared to the polyol process. In addition, we investigate the rheological behavior of the synthesized AgNW-based conductive ink under screen printing and direct writing conditions using flow sweep, peak hold, and frequency sweep tests. The rheological behavior of the AgNWbased conductive ink provides valuable information regarding its use for various printing applications. The conductive ink demonstrated a shear-thinning thixotropic behavior for all silver nanostructure contents (2, 5, 10, and 20 wt.%), and all temperatures (25, 30, and 40 °C). It was observed that direct writing is better suited for printing inks with low colloidal content due to its lower shear rate, whereas screen printing is more effective for high-content, high-viscosity inks because it utilizes higher shear rates. The proposed cheaper and more sustainable method can serve as a promising alternative for industrial conductive ink manufacturing for printed electronic appliances such as printed circuit boards (PCBs) and flexible transparent conductive films (TCFs).

Efficient Synthesis of Liquid Photonic Crystal by Electrically-Driven Colloid Concentration

2025-02-28T17:28:01+08:00

Article

Efficient Synthesis of Liquid Photonic Crystal by Electrically-Driven Colloid Concentration

Xiaodong Lu ^1,†, Huimin Zhu ^1,†, Sheng Chen ¹, Ximeng Lv ¹, and Jianping Ge ^1,2,*

¹State Key Laboratory of Petroleum Molecular & Process Engineering, Shanghai Key Laboratory of Green Chemistry and Chemical Processes, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China

²Institute of Eco-Chongming, Shanghai 202162, China

* Correspondence: jpge@chem.ecnu.edu.cn

† These authors contributed equally to this work.

Received: 9 January 2025; Revised: 19 February 2025; Accepted: 21 February 2025; Published: 28 February 2025

Abstract: Liquid photonic crystal (LPC) is a promising new material in the field of sensing, display, printing, and coating due to its unique fluidity, metastability, and reversibility in colloidal assembly. However, it is a big challenge to prepare LPC materials in an efficient, controllable, and eco-friendly way. In this work, an electrically-driven colloid concentration process was developed for the efficient synthesis of LPC. The key for the synthesis was that the electrophoretic process produced a locally concentrated but “agglomeration-free” colloidal solution, which spontaneously turned to LPC after being kept standing for a few minutes. The synthesis possessed good universality and reproducibility for LPCs composed of different particles and solvents. Its efficiency could be improved by tuning the particles’ surface charge, the dielectric constant and viscosity of the solvent, as well as the external field conditions. More importantly, it could be developed into a large-scale and green process without chemical wastes compared to the previous synthetic methods.

Noble-Metal Nanocrystals: From Synthesis to Biomedical Applications

2025-02-28T17:37:08+08:00

Perspective

Noble-Metal Nanocrystals: From Synthesis to Biomedical Applications

Yidan Chen ¹, Emily Yan ², and Younan Xia ^2,*

¹School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA

²Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30332, USA

* Correspondence: younan.xia@bme.gatech.edu

Received: 24 February 2025; Accepted: 26 February 2025; Published: 28 February 2025

Abstract: Noble metals hold promises for a variety of biomedical applications due to their unique physical and biochemical properties. To unlock this potential, a significant amount of research has been dedicated to the controlled synthesis of noble-metal nanocrystals over the past two decades, with a particular emphasis on the production of Au and Ag nanocrystals with diverse and well-controlled shapes. The successful synthesis of noble-metal nanocrystals with tunable sizes, shapes, and morphologies allows researchers to explore their use in a range of biomedical applications, including contrast enhancement for an array of bioimaging modalities, facilitating stimuli-responsive drug delivery, and functioning as antimicrobial or anticancer agents.

Quantification of Nanomaterial Surfaces

2025-03-10T10:04:16+08:00

Review

Quantification of Nanomaterial Surfaces

Harshit Kumar and Mingdi Yan *

Department of Chemistry, University of Massachusetts Lowell, 1 University Avenue, Lowell, MA 01854, USA

* Correspondence: Mingdi_Yan@uml.edu

Received: 24 February 2025; Revised: 3 March 2025; Accepted: 5 March 2025; Published: 10 March 2025

Abstract: Quantification of nanomaterial surfaces is critical in the design of nanomaterials with predictable and tailored functions. Nanomaterials exhibit unique surface properties, such as high surface-to-volume ratios and tunable chemistry, which govern their stability, reactivity, and functions in a wide range of applications including catalysis, drug delivery, bioimaging, and environmental remediation. However, quantitative analysis of the nanomaterial surface is challenging due to the inherent heterogeneity, which affects the surface structure, ligand density and presentation. This mini review discusses several important aspects of surface quantification, including ligand structure, ligand density, functional groups, and surface reactions. Traditional analytical methods, such as nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and UV-vis spectroscopy, as well as emerging techniques that offer higher spatial resolution and sensitivity are discussed, and examples are given.

Chameleon-Inspired Color-Changeable Colloidal Photonic Crystal Films Sensitive to Human Body Temperature

2025-03-24T17:36:14+08:00

Article

Chameleon-Inspired Color-Changeable Colloidal Photonic Crystal Films Sensitive to Human Body Temperature

Toshimitsu Kanai *, Mari Sato, and Yuna Hirano

Graduate School of Engineering Science, Yokohama National University, 79-5 Tokiwadai, Hodogaya-ku, Yokohama 240-8501, Japan

* Correspondence: tkanai@ynu.ac.jp

Received: 6 February 2025; Revised: 21 March 2025; Accepted: 24 March 2025; Published: 24 March 2025

Abstract: Artificial chameleon skins have been developed using advanced materials, such as photonic crystals, for camouflage and thermoregulation. However, to respond to subtle changes in human body temperature, the thermosensitivity, quality, and color response of these biomimetic films need to be improved. We report the development of chameleon-inspired color-changeable films with enhanced sensitivity to changes in the human body temperature. Non-close-packed colloidal photonic crystals were immobilized in a thermosensitive poly(N-isopropylacrylamide) (PNIPAM) hydrogel film and simultaneously attached to a flexible polyethylene terephthalate (PET) sheet by photopolymerization. The attachment to the PET sheet ensured high thermosensitivity and film quality besides ease of use. The film displayed full color spectrum from red to violet within a small range (~3 °C) of human body temperature without any change in the film area and film distortion. The temperature range of the full color spectrum was easily tuned by adding a poor solvent, ethylene glycol, to PNIPAM. The film attached to a human arm exhibited color changes from red to yellow, light green, and blue in response to changes in the body temperature without external heat. This study could contribute to the basic research and practical applications of artificial chameleon skins.

Magnetically-Driven Reconfigurable Cilium Array with Tunable Wettability for Dynamic Display and Controllable Microreaction

2025-03-28T16:27:09+08:00

Article

Magnetically-Driven Reconfigurable Cilium Array with Tunable Wettability for Dynamic Display and Controllable Microreaction

Zijing Quan ¹, Yuhan Zhang ^1,*, You Pan ¹, Zhongyi Yang ¹, You Chen ¹, Fawei Rui ¹, Letian Li ¹, Bo Li ^1,²^,*, Shichao Niu ^1,2,3,*, Zhiwu Han ^1,2,3, and Luquan Ren ^1,2,3

¹Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University, Changchun 130022, China

²National Key Laboratory of Automotive Chassis Integration and Bionics, Jilin University, Changchun 130022, China

³Institute of Structured and Architected Materials, Liaoning Academy of Materials, Shenyang 110167, China

* Correspondence: yhzhang9922@mails.jlu.edu.cn (Y.Z.); boli@jlu.edu.cn (B.L.); niushichao@jlu.edu.cn (S.N.)

Received: 3 March 2025; Revised: 17 March 2025; Accepted: 25 March 2025; Published: 28 March 2025

Abstract: Efficient droplet transport plays an important role in many fields such as liquid collection, microfluidic management, and reaction control. However, it remains a key challenge to achieve fast and precise droplet motion control along a predetermined path. Herein, a magnetically driven cilium array (MDCA) was developed by a simple one-step spraying method. The MDCA exhibits both upright and prostrated states under a programmable magnetic field, achieving in-situ pinning and driving of the droplets, respectively. In particular, the MDCA modified by the silicone oil can not only be used for precise droplet manipulation on the spatio-temporal scale (S-shaped trajectory transport, selective control of target droplets, and velocity control) but also provides a self-enclosed space for droplet fusion for chemical microreactions, allowing fine-tuning of reaction parameters and isolation from external contamination. Based on the theoretical analysis of droplet transport, MDCA can be applied to the development of dynamic digital displays and chemical microreactors and provides inspiration for the development of environmental monitoring, drug delivery, and energy purification.

Polymer-Patched Plasmonic Nanoparticles

2025-03-29T08:00:09+08:00

Review

Polymer-Patched Plasmonic Nanoparticles

Chansong Kim ¹, Xiaoying Lin ¹, Jiyeon Kim ¹, Yangming Wang ¹, and Qian Chen ^1,2,3,4,*

¹Department of Materials Science and Engineering, the Grainger College of Engineering, University of Illinois,
Urbana, IL 61801, USA

²Materials Research Laboratory, University of Illinois, Urbana, IL 61801, USA

³Department of Chemistry, University of Illinois, Urbana, IL 61801, USA

⁴Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, IL 61801, USA

* Correspondence: qchen20@illinois.edu

Received: 3 March 2025; Revised: 22 March 2025; Accepted: 25 March 2025; Published: 29 March 2025

Abstract: In this work, we discuss advancements at the intersection of surface patchiness design and plasmonic nanoparticles. Surface patchiness design, inspired by nature’s strategy to encode complex functions by spatially distributed surface patterns, has become increasingly popular in nanoparticle research. The surface patterns lead to their nonuniformity in chemical and physical properties, enabling not only their application as functional hybrid nanomaterials but as building blocks for self-assembly through directional interactions for applications in catalysis, biomedicine, sensing, robotics, and metamaterials. When surface patchiness design is implemented on plasmonic nanoparticles, interesting coupling of plasmonic resonance emerges from self-assembly structures not easily available from non-patchy nanoparticles. This direction is rapidly evolving and we review efforts in the synthesis, self-assembly, and applications of plasmonic patchy nanoparticles. We conclude with outlook discussions of the future opportunities of this field.

Materials and Interfaces

Size-Controlled Synthesis of Rhodium Nanocatalysts and Applications in Low-Temperature Hydroformylation

Size-Controlled Synthesis of Rhodium Nanocatalysts and Applications in Low-Temperature Hydroformylation

Constructing Co Cluster Sites for Selective CO2 Hydrogenation via Phase Segregation from Co-Doped TiO2 Nanocrystals

Constructing Co Cluster Sites for Selective CO2 Hydrogenation via Phase Segregation from Co-Doped TiO2 Nanocrystals

Intrinsically Multi-Color Device Based on Dynamic Cooperation of Molecular Switches and Metal Ions

Intrinsically Multi-Color Device Based on Dynamic Cooperation of Molecular Switches and Metal Ions

High-Yield, Environmentally-Friendly, and Sustainable Synthesis of Silver Nanowires Using Tannic Acid and Their Application in Conductive Ink Preparation: Economic Analysis and Rheological Investigation

High-Yield, Environmentally-Friendly, and Sustainable Synthesis of Silver Nanowires Using Tannic Acid and Their Application in Conductive Ink Preparation: Economic Analysis and Rheological Investigation

Efficient Synthesis of Liquid Photonic Crystal by Electrically-Driven Colloid Concentration

Efficient Synthesis of Liquid Photonic Crystal by Electrically-Driven Colloid Concentration

Noble-Metal Nanocrystals: From Synthesis to Biomedical Applications

Noble-Metal Nanocrystals: From Synthesis to Biomedical Applications

Quantification of Nanomaterial Surfaces

Quantification of Nanomaterial Surfaces

Chameleon-Inspired Color-Changeable Colloidal Photonic Crystal Films Sensitive to Human Body Temperature

Chameleon-Inspired Color-Changeable Colloidal Photonic Crystal Films Sensitive to Human Body Temperature

Magnetically-Driven Reconfigurable Cilium Array with Tunable Wettability for Dynamic Display and Controllable Microreaction

Magnetically-Driven Reconfigurable Cilium Array with Tunable Wettability for Dynamic Display and Controllable Microreaction

Polymer-Patched Plasmonic Nanoparticles

Polymer-Patched Plasmonic Nanoparticles

Constructing Co Cluster Sites for Selective CO₂ Hydrogenation via Phase Segregation from Co-Doped TiO₂ Nanocrystals

Constructing Co Cluster Sites for Selective CO₂ Hydrogenation via Phase Segregation from Co-Doped TiO₂ Nanocrystals