A new method using nanowires can make solar panels much more efficient and much cheaper

A probe radical astatine the Norwegian University of Science and Technology (NTNU) has developed a method for making an ultra-high worldly businesslike star compartment utilizing semiconductor nanowires. If this is placed connected apical of a accepted silicon-based star cell, it could perchance treble the ratio of today's Si star cells astatine debased cost.

"We person a caller method of utilizing gallium arsenide (GaAs) worldly successful a precise effectual mode done nanostructuring, truthful we tin marque solar cells overmuch much businesslike utilizing lone a tiny fraction of the worldly that is usually used," says Anjan Mukherjee, a Ph.D. campaigner astatine the Department of Electronic Systems. Mukherjee is the main developer of the technique.

Gallium arsenide (GaAs) is the champion worldly for making precocious ratio star cells due to the fact that of its bonzer airy absorption and electrical characteristics. It is commonly utilized to marque solar panels chiefly for usage successful space.

However, high-quality GaAs star compartment components are rather costly to make, which has driven a request for techniques that tin chopped the usage of the material.

In caller years, it is realized that a nanowire operation tin perchance heighten star compartment ratio compared to modular planar star cells, adjacent arsenic little worldly is used.

"Our probe radical has recovered a caller mode to marque an ultrahigh power-per-weight ratio star compartment that is much than 10 times much businesslike than immoderate different star cell, by utilizing GaAs successful a nanowire structure," says Helge Weman, a prof astatine the Department of Electronic Systems astatine NTNU.

The group's probe has been published successful ACS Photonics, a diary from the American Chemical Society.

Pioneering method

GaAs star cells are astir often grown connected a heavy and costly GaAs substrate, which leaves small country for reducing costs.

"Our method uses a vertically lasting semiconductor nanowire array operation connected a inexpensive and industry-favorable Si level to turn the nanowires," Weman said.

"The astir cost-effective and businesslike solution is to turn a dual tandem cell, with a GaAs nanowire compartment connected the apical grown connected a bottommost Si cell, which avoids the usage of an costly GaAs substrate. We person worked to minimize the outgo of increasing the apical GaAs nanowire cell, due to the fact that it's the GaAs fabrication outgo that is 1 of the large issues that is presently holding backmost the technology," Weman explains.

"The tiny footprint of the nanowire operation provides an further benefit, due to the fact that it allows for precocious prime successful crystals successful the nanowire and successful the interface with the silicon. This helps amended the star compartment performance," said Bjorn-Ove Fimland, a prof successful the aforesaid department.

The improvement of this exertion tin beryllium straightforward and cost-effective with due investments and industrial-scale R&D projects.

"We turn the nanowires utilizing a method called MBE (molecular beam epitaxy), which is not a instrumentality that tin nutrient materials astatine a precocious volume. However, it's imaginable to nutrient these nanowire-based star cells astatine a ample standard by utilizing an industrial-scale instrumentality specified arsenic MOCVD (metal integrated vapor deposition)," Mukherjee said.

Integrating this merchandise connected apical of a Si compartment tin perchance amended star compartment ratio to arsenic overmuch arsenic 40 % – which would mean a doubling of ratio erstwhile compared to today's commercialized Si star cells.

Suitable for abstraction travel

The researchers accidental their attack could beryllium adapted truthful that the nanowires are grown connected antithetic substrates, which could unfastened the doorway to galore different applications.

"We are exploring increasing this benignant of light-weight nanowire operation connected atomically bladed two-dimensional substrates specified arsenic graphene. This could unfastened up tremendous opportunities to nutrient light-weight and flexible star cells that tin beryllium utilized successful self-powered drones, micro-satellites and different abstraction applications," Mukherjee said.

---

---