Thermochromic Smart Windows Assisted by Photothermal Nanomaterials

Abstract

Thermochromic smart windows are optical devices that can regulate their optical properties actively in response to external temperature changes. Due to their simple structures and as they do not require other additional energy supply devices, they have great potential in building energy-saving. However, conventional thermochromic smart windows generally have problems with high response temperatures and low response rates. Owing to their great effect in photothermal conversion, photothermal materials are often used in smart windows to assist phase transition so that they can quickly achieve the dual regulation of light and heat at room temperature. Based on this, research progress on the phase transition of photothermal material-assisted thermochromic smart windows is summarized. In this paper, the phase transition mechanisms of several thermochromic materials (VO2, liquid crystals, and hydrogels) commonly used in the field of smart windows are introduced. Additionally, the applications of carbon-based nanomaterials, noble metal nanoparticles, and semiconductor (metal oxygen/sulfide) nanomaterials in thermochromic smart windows are summarized. The current challenges and solutions are further indicated and future research directions are also proposed.

Novel sunlight-driven Cu7S4/VO2 composite films for smart windows

“…[14][15][16] For example, vanadium dioxide (VO 2 ), as a high-performing inorganic thermochromic material, can regulate the near-infrared band without affecting the visible light transmittance and has been widely used in smart window devices. [17][18][19][20][21][22][23][24] However, there are still challenges, such as high phase transition temperature and poor optical performance in practical applications. [25][26][27][28] Previously, doping methods using high-valence ions such as W 6+ 29-31 and Mo 6+ 32,33 have been commonly used to reduce the phase transition temperature of VO 2 , but this often brought in defects that weakened its optical performance.…”

Flame-Retardant and Form-Stable Delignified Wood-Based Phase Change Composites with Superior Energy Storage Density and Reversible Thermochromic Properties for Visual Thermoregulation

“…Recently, phosphorus–nitrogen-containing intumescent flame retardants (P/N-FRs) have shown tremendous application prospects in flame retardance of wood owing to being halogen-free, high flame retardancy, low toxicity, and less smoke . P/N-FRs can efficiently limit the intense burning of wood by promoting char formation (condensed phase) and reducing flammable volatile breakdown products (gas phase) when exposed to flame. − Furthermore, a synergistic effect will be generated between phosphorus and nitrogen in P/N-FRs during combustion, which is conducive to superior flame-retardant efficiency. − During energy storage and release, visible temperature change and real-time monitoring of PCMs can bring convenience to people’s life and production. − Therefore, it is advantageous to incorporate a thermochromic material into phase change composites to determine the ambient temperature without a thermometer. To the best of our knowledge, no literature has reported the exploitation of wood-based form-stable composite PCMs simultaneously with high energy storage density, excellent flame retardancy, and real-time and visual reversible thermochromic properties.…”

Machine Learning-Assisted Synthesis of Two-Dimensional Materials

“…MoS 2 is considered to be a typical 2D material, with unique electronic properties and considerable band gap modulation, , which exhibits promising applications in the fields of electronic devices, photodetectors, , and optoelectronic devices. , However, the controlled synthesis of high-quality MoS 2 is a significant challenge at present. In order to demonstrate the feasibility of ML to optimize and accelerate the synthesis of 2D materials, in this paper, XGBoost, Support Vector Machine (SVM), Naïve Bayes (NB), and Multilayer Perceptron (MLP) four algorithms in ML were used to explore the parameters of successful synthesis of MoS 2 by CVD.…”