Scientists have found a way to push perovskite solar cells to an energy efficiency of 25% – which could eventually lead to a replacement of silicon solar cells
The landmark IPCC Report linked “human influence” to increases in every single measurement of climate change, from a change in rainfall patterns to the carbon absorption of forests, to the melting of glaciers.
However, the authors say that decisive action, especially in limiting carbon emissions – central to many of the crises – can change the destructive outcome for Earth.
Part of that fight against carbon emissions lies in replacing global fossil fuels, with something clean and functional.
Solar energy is a good alternative for fossil fuels, but it needs to be cheaper
Solar energy is a common option in warmer climates, but is notoriously expensive. Individuals have to decide if they want their residential home to run on solar power, then figure out if the costs will pay off.
While some countries in the Global North offer subsidies for implementation of solar cells, there is an issue at the basic level – the silicon used to make solar panels is quite expensive. On top of that, it can only be manufactured in stiff sheets, meaning that only a certain kind of building can attempt solar energy.
Co-lead author Professor Nicholas Long, from the Department of Chemistry at Imperial, said: “Silicon cells are efficient but expensive, and we urgently need new solar energy devices to accelerate the transition to renewable energy.”
An unexpected collaboration leads to improved perovskite solar cells
Now, scientists at Imperial College London offer another route – what if there was a functional alternative material for solar cells?
Traditionally, perovskite solar cells are cheaper than silicon. They can actually be printed from inks, which also gives them the edge when it comes to weight and flexibility. Unfortunately, they can’t stand a normal environment. A little bit of excessive weather can disable perovskite solar cells, which leave them functionally redundant.
Professor Long further said: “Stable and efficient perovskite cells could ultimately allow solar energy to be used in more applications – from powering the developing world to charging a new generation of wearable devices.”
Solving the perovskite solar cell problem with a new material, ferrocenes
Working around the inevitability of fragility, a team from City University of Hong Kong used Imperial College London-made ferrocenes into perovskite solar cells. The findings, published in the journal Science, show that ferrocene-infused perovskite solar cells could become a viable alternative for silicon.
Ferrocenes are compounds with iron at their centre, surrounded by sandwiching rings of carbon. One property their structure gives them is excellent electron richness, which in this case allows electrons to move more easily from the perovskite layer to subsequent layers, improving the efficiency of converting solar energy to electricity.
Lead researcher Dr Zonglong Zhu from City University of Hong Kong, said: “We are the first team to successfully boost the inverted perovskite solar cell to a record-high efficiency of 25% and pass the stability test set by the International Electrotechnical Commission.”
The collaborative team hope to bring this product to the market, after further testing to make the improved perovskite solar cells as energy efficient as possible.