Titanium Dioxide Nanomaterials: Synthesis, Properties, Modifications, and Applications

Dye-sensitized solar cells (DSCs) offer the possibilities to design solar cells with a large flexibility in shape, color, and transparency. DSC research groups have been established around the worl ...

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Dye-Sensitized Solar Cells

The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102

Chemistry and properties of nanocrystals of different shapes.

Recent developments have greatly improved the sensitivity of optical sensors based on metal nanoparticle arrays and single nanoparticles. We introduce the localized surface plasmon resonance (LSPR) sensor and describe how its exquisite sensitivity to size, shape and environment can be harnessed to detect molecular binding events and changes in molecular conformation. We then describe recent progress in three areas representing the most significant challenges: pushing sensitivity towards the single-molecule detection limit, combining LSPR with complementary molecular identification techniques such as surface-enhanced Raman spectroscopy, and practical development of sensors and instrumentation for routine use and high-throughput detection. This review highlights several exceptionally promising research directions and discusses how diverse applications of plasmonic nanoparticles can be integrated in the near future.

Biosensing with plasmonic nanosensors

2.3. Evaluation of Photocatalytic Water Splitting 6507 2.3.1. Photocatalytic Activity 6507 2.3.2. Photocatalytic Stability 6507 3. UV-Active Photocatalysts for Water Splitting 6507 3.1. d0 Metal Oxide Photocatalyts 6507 3.1.1. Ti-, Zr-Based Oxides 6507 3.1.2. Nb-, Ta-Based Oxides 6514 3.1.3. W-, Mo-Based Oxides 6517 3.1.4. Other d0 Metal Oxides 6518 3.2. d10 Metal Oxide Photocatalyts 6518 3.3. f0 Metal Oxide Photocatalysts 6518 3.4. Nonoxide Photocatalysts 6518 4. Approaches to Modifying the Electronic Band Structure for Visible-Light Harvesting 6519

Semiconductor-based Photocatalytic Hydrogen Generation

Herein, unique bimetallic phosphide of NiCoP with nanosheet structure coated on carbon cloth ([email protected]) was synthesized. Three-dimensional cobalt-based ZIF-67 (Co-ZIF-67) with dodecahedron morphology was first grown on carbon cloth, and then the NiCoP nanosheets were formed through a synthesis procedure involving Ni2+-induced template scarification of the Co-ZIF-67 and the phosphorization calcination. Impressively, the resulting [email protected] electrode shows a remarkable specific capacity of 1149.2 C g−1 (6.09 C cm−2) at 1 A g−1 and superior cycle performance (the capacity retains 99.7 % after cycled for 10,000 cycles at 6 A g−1), owing to the optimized ZIF-67-template modification, unique morphology, good electronic conductivity, superiority of the bimetallic phosphides, and the battery type feature. Further, a solid-state asymmetric supercapacitor (ASC) was fabricated by using the obtained [email protected] as the cathode and using active carbon (AC) as the anode. The assembled ASC device delivers a high specific energy of 78.5 Wh kg−1 at the specific power of 799.5 W kg−1, and remains 90.3 % capacity retention over 10,000 cycles at 8 A g−1, demonstrating its high potential for applications in the field of high-capacity supercapacitors. These results illustrate the promise of [email protected] as a promising cathode material in supercapacitor. 

ZIF-67 derived NiCoP nanosheets on carbon cloth as a flexible cathode for high-performance solid-state asymmetric supercapacitors

ABSTRACT Polycarbonate is a commonly used plastic, particularly for making glasses lenses. Polycarbonate is prone to fogging, making hydrophilic modification desirable. In this work, polycarbonate is treated with p-phenylenediamine (PPD) to improve its hydrophilicity. The influence of treating conditions, such as solvent, PPD concentration, heating temperature, and heating time, are studied to reveal their impacts on the water contact angle of polycarbonate. For example, the water contact angle of polycarbonate is reduced to 33° from 83° after treated in water with 0.1 wt% PPD at 80°C for 120 minutes. The improvement of the hydrophilicity of polycarbonate by PPD is explained based on the introduction of polar groups by PPD or poly-PPD (p-PPD), in terms of polyurethane, benzyl hydroxyl, or amine centers, which can interact with water to have a better affinity to spread water on the surface due to the like-like principle. The possible mechanisms are supported with infrared spectroscopy measurements. GRAPHICAL ABSTRACT

Hydrophilic modification of polycarbonate using p-phenylenediamine

Nanomaterials for Renewable Energy Production and Storage

Understanding the decay of correlations in time for (1+1)-dimensional polymer models in the KPZ universality class has been a challenging topic. Following numerical studies by physicists, concrete conjectures were formulated by Ferrari and Spohn (Ferrari-Spohn '16) in the context of planar exponential last passage percolation. These have mostly been resolved by various authors. In the context of positive temperature lattice models, however, these questions have remained open. We consider the time correlation problem for the exactly solvable inverse-gamma polymer in $\mathbb{Z}^2$. We establish, up to constant factors, upper and lower bounds on the correlation between free energy functions for two polymers rooted at the origin (droplet initial condition) when the endpoints are either close together or far apart. We find the same exponents as predicted in (Ferrari-Spohn '16). Our arguments rely on the understanding of stationary polymers, coupling, and random walk comparison. We use recently established moderate deviation estimates for the free energy. In particular, we do not require asymptotic analysis of complicated exact formulae.

Xiaobo Chen

Papers

ZIF-67 derived NiCoP nanosheets on carbon cloth as a flexible cathode for high-performance solid-state asymmetric supercapacitors

Hydrophilic modification of polycarbonate using p-phenylenediamine

Nanomaterials for Renewable Energy Production and Storage

Temporal correlation in the inverse-gamma polymer

Temperature characteristics analysis of a Tm3+-doped heterogeneous helical cladding fiber amplifier