One-step ball milling synthesis of VO2 (M) nanoparticles with exemplary thermochromic performance

Abstract

Vanadium dioxide (VO2) has demonstrated highly potential for smart windows because of its thermochromic property. This study represents the development of a facile but efficient method for the synthesis of VO2 (M) nanoparticles by ball milling method under ambient conditions, without release of waste liquid or gases. The key variables related to synthesis, including milling time and molar ratio of raw materials, have been investigated. It was found that the pure-phase VO2 (M) nanoparticles with the sizes of the particles ranged from 20 to 50 nm and relatively good dispersivity could be prepared by optimizing process parameters. For practice use to decrease the phase transition temperature, elemental W doping amount of 2 at.%, V1−xWxO2 (M) nanoparticles were also studied, and their glass coating exhibits high thermochromic performance with luminous transmittance (Tlum) of 44.18%, solar regulation efficiency (∆Tsol) of 9.64%, and the critical phase transition temperature (Tc) of ~ 42 °C. This work demonstrates a green and promising ball milling method to fabricate large scale VO2 (M) and V1−xWxO2 (M) nanoparticles for smart windows.

Vibrational properties of the mechanochemically synthesized Cu2SnS3: Raman study

“…Extended milling leads to a decrease of the grain size and phase transformation of the m-CTS into a t-CTS as well as CuS into Cu 2 S. This phenomenon, phase transitions induced by milling are common, especially for sulphides [56] and for many oxides. [57,58] There are no significant differences between modes intensities measured at point 1 and 2. The most intense modes at both measured points can be assigned to tetragonal CTS phase mode at 335 cm À1 .…”

Thermochromic Vanadium Dioxide Nanostructures for Smart Windows and Radiative Cooling

“…Although VO 2 is IR-transparent in its lowtemperature insulating state and IR-reflective in its hightemperature metallic state, suitable for NIR regulation in thermochromic windows, it exhibits unfavorable regulation of thermal emittance, with high emittance at low temperatures and low emittance at high temperatures. [2,32,42] Therefore, the adaptive and selective regulation of solar and thermal radiation is still challenging to develop ideal smart windows based on VO 2 for building energy saving. [3,18,150] Environmental stability or durability is also an important challenge for the practical VO 2based applications with desirable thermochromic properties.…”

“…[40] High-energy milling of precursor powders leads to preparation of a nanocomposite structure which reacts during milling to form a mixture of discrete nanocrystals within a water-washable salt matrix. [41,42] The process is potential in terms of industrialization since it requires shorter preparation time and less pollution than the hydrothermal synthesis. Wang et al [43] prepared the VO 2 (M) nanoparticles of size ranging from 20 to 50 nm by onestep ball milling with activated carbon as the reductant.…”

“…Such a mechanochemical procedure enables preparing various oxides with lower oxidation number or suboxides [40] . High‐energy milling of precursor powders leads to preparation of a nanocomposite structure which reacts during milling to form a mixture of discrete nanocrystals within a water‐washable salt matrix [41,42] . The process is potential in terms of industrialization since it requires shorter preparation time and less pollution than the hydrothermal synthesis.…”

“…Summary of approaches to fabricate VO 2 (M) films. Reproduced with permission from Ref [42],. Copyright 2021, Springer Nature.…”