Quantum Dot Wars Continue in Europe

The ÖKO Institut of Germany – a research organisation that focuses on sustainability – has said that there are currently ‘no alternatives’ on the market that match the performance of quantum dots containing the (potentially harmful) material, cadmium selenide.

The Institut supports the exemption of cadmium QDs from Europe’s RoHS regulation (a vote was taken on the possibility of an extension in May last year, and rejected by 618 votes to 33), and recommends that it be extended. A report on the subject can be found at

QD Vision, a manufacturer of cadmium QDs, claims that the use of these components would, in fact, lower the amount of free cadmium in the environment. This is due to the higher energy efficiency of QD displays; fossil fuel-powered electrical production plants are a significant contributor to cadmium pollution.

Nanoco, which produces cadmium-free QDs, has responded to the report, calling it ‘inconclusive’. The firm highlights several issues with the document – and points out that the Institut earlier supported an end to the exemption allowing cadmium to be used in LED lighting.

The Institut’s report ‘acknowledges the presence of cadmium-free alternatives as present in the marketplace and that the performance standards of both technologies are similar under different test conditions,’ writes Nanoco. The results are not definitive. For example, it offers no indication of what level of (alleged) colour gamut improvement or energy savings should be regarded as sufficient to warrant an RoHS exemption.

Other concerns are related to the findings on toxicity, energy savings and colour performance.

Nanoco argues that the Institut ‘fails to evaluate clear scientific data’ on the relative toxicity of cadmium/cadmium-free QDs, as well as contradicting the earlier LED lighting recommendation mentioned above.

In terms of power consumption, the report states that the claimed advantages for cadmium QDs depend on the display product in which they are being used. It also, says Nanoco, ignores the data showing that commercial TVs with cadmium-free QDs (i.e., Samsung’s) have lower energy consumption than those using cadmium components.

On colour, the report accepts the claims of higher colour gamut performance for cadmium QDs – but also states that ‘the consultants understand the results to be inconclusive.’ It also does not deal with the DCI-P3 gamut, which is referenced in the new UltraHD Premium specification.

Michael Edelman, CEO of Nanoco, finished the firm’s response. He said, “It is surprising that three years ago the Öko Institute recommended the extension of cadmium for displays based on the lack of suitable alternatives not being available until 2019. They were on shelves by March 2015. Despite saying energy efficiency was not a deciding criteria in their 2014 report, they now seem to have decided suddenly that it is the critical factor on advocating the new extension.”

Analyst Comment

We had the chance to talk to Edelman about this dispute. He is clearly very frustrated that, although exemptions to the ROHS regulations are generally only given where there is no way to avoid the material or where the balance of overall good is in favour of an exemption (for example, that was the reason for the exemption given for mercury in LCD backlights. CCFLs that used mercury were much more efficient, so less power was used, so less mercury was released from power stations.) From Edelman’s point of view, his company has spent around $50 million to $60 million to develop QDs that don’t have cadmium, to meet the ROHS regulations, but there is an exemption to allow those that have got cadmium are allowed to produce products.

The institute rejected that argument last time, and Edelman said that it is unclear why it accepted it this time. I have (rapidly) been through the report and I have some sympathy with the Nanoco argument. Although there is a lot of discussion about the better efficiency of cadmium QDs, the example of the Samsung SUHD set shows that there are other factors that are important in power consumption of TVs and if care is taken in overall system design, good power efficiency can be achieved. This is shown in the report as the Samsung set is the only one that reaches A+ level.

The consultants also seem to have taken into account arguments about colour performance. However, the report shows little (or no) understanding of the importance of the different colour gamuts in the market. For example, in several places there is an argument about better colour being useful for medical diagnostics, but there is no reference to the fact that there are no equivalents of Dicom for colour displays, and it’s not impossible (although unlikely) that medical standards being developed end up having quite a limited gamut. We shall see. In my attendance at Medical technology events, I have yet to hear a market actor say that they are seeing demand for wider gamuts.

Of course, the recommendation is only that and the decision will be taken by the Commission and the Parliament. It would be hard, and surprising, for the Commission to not adopt the recommendation and bring a proposal to the Parliament. Once there, political considerations will, no doubt be dominant. I found it hard work to wade through the details of the document – I can’t imagine many MEPs taking the time. So, I suspect, the final decision might depend on the political climate between the Commission and the Parliament. I’m not close enough to that (thank goodness) to second guess it.

While we were on the phone, we talked to Edelman briefly about developments. As we have previously reported, Nanoco has changed its deal with Dow (which was exclusive) and is now developing its capacity to make the basic QDs itself, while Dow continues as a licensee. This will allow Nanoco to boost production and you can expect more announcements about partners, including film makers.

As far as we can tell, without an exemption, companies that are currently shipping products with cadmium-based QDs in Europe are in breach of the ROHS regulations, although there is little being done to enforce that, as far as we can see. No doubt, given the unpopularity of the EU institutions at the moment, the Commission is taking a ‘pragmatic’ line – not the first time we have seen apparent non-enforcement of regulations.