4 research outputs found
Reliable Manipulation of Gas Bubble Size on Superaerophilic Cones in Aqueous Media
Gas bubbles in aqueous
media are ubiquitous in a broad range of
applications. In most cases, the size of the bubbles must be manipulated
precisely. However, it is very difficult to control the size of gas
bubbles. The size of gas bubbles is affected by many factors both
during and after the generation process. Thus, precise manipulation
of gas bubble size still remains a great challenge. The ratchet and
conical hairs of the Chinese brush enable it to realize a significant
capacity for holding ink and transferring them onto paper continuously
and controllably. Inspired by this, a superhydrophobic/superaerophilic
cone interface is developed to manipulate gas bubble size in aqueous
media. When the resultant force between the Laplace force and the
axial component of the buoyancy force approaches zero, the gas bubble
is held steadily by the superhydrophobic/superaerophilic copper cones
in a unique position (balance position). A new kind of pressure sensor
is also designed based on this principle
Reliable Manipulation of Gas Bubble Size on Superaerophilic Cones in Aqueous Media
Gas bubbles in aqueous
media are ubiquitous in a broad range of
applications. In most cases, the size of the bubbles must be manipulated
precisely. However, it is very difficult to control the size of gas
bubbles. The size of gas bubbles is affected by many factors both
during and after the generation process. Thus, precise manipulation
of gas bubble size still remains a great challenge. The ratchet and
conical hairs of the Chinese brush enable it to realize a significant
capacity for holding ink and transferring them onto paper continuously
and controllably. Inspired by this, a superhydrophobic/superaerophilic
cone interface is developed to manipulate gas bubble size in aqueous
media. When the resultant force between the Laplace force and the
axial component of the buoyancy force approaches zero, the gas bubble
is held steadily by the superhydrophobic/superaerophilic copper cones
in a unique position (balance position). A new kind of pressure sensor
is also designed based on this principle
Reliable Manipulation of Gas Bubble Size on Superaerophilic Cones in Aqueous Media
Gas bubbles in aqueous
media are ubiquitous in a broad range of
applications. In most cases, the size of the bubbles must be manipulated
precisely. However, it is very difficult to control the size of gas
bubbles. The size of gas bubbles is affected by many factors both
during and after the generation process. Thus, precise manipulation
of gas bubble size still remains a great challenge. The ratchet and
conical hairs of the Chinese brush enable it to realize a significant
capacity for holding ink and transferring them onto paper continuously
and controllably. Inspired by this, a superhydrophobic/superaerophilic
cone interface is developed to manipulate gas bubble size in aqueous
media. When the resultant force between the Laplace force and the
axial component of the buoyancy force approaches zero, the gas bubble
is held steadily by the superhydrophobic/superaerophilic copper cones
in a unique position (balance position). A new kind of pressure sensor
is also designed based on this principle
Annealing-Free SnO<sub>2</sub> Layers for Improved Fill Factor of Perovskite Solar Cells
Perovskite
solar cells (PSCs) have developed rapidly with simplified
planar structures, in which the electron transport layer (ETL) is
one of the key components for high efficiency. As one of the most
widely used ETLs for PSCs, a tin dioxide (SnO2) ETL is
usually obtained by thermal annealing at around 150 °C, which
complicates the fabrication process and confines the application of
PSCs onto thermally sensitive flexible substrates. Here, we adopted
an annealing-free process for the first time, the negative pressure
evaporation (NPE) method, to quickly prepare SnO2 ETLs
(NPE-SnO2) within 1 minute at room temperature from widely
used commercial aqueous SnO2 colloid. The NPE process developed
here significantly improves the surface morphology and conductivity
of SnO2 layers compared to the traditional thermally annealed
ones (A-SnO2). Detailed characterizations reveal that increased
oxygen vacancies and reduced hydroxyl defects contribute to higher
conductivity of NPE-SnO2 and less interfacial recombination
of PSCs. Therefore, a PSC with NPE-SnO2 delivers an improved
fill factor (FF) of 82.33% and a higher power conversion efficiency
(PCE) of 23.07%, which is the highest value based on annealing-free
SnO2. To conclude, the NPE process is a universal technique
to obtain high-quality semiconductor films from their wet state within
1 min and opens up the possibility of fabricating functional layers
of PSCs without thermal annealing