Silicon is one of the most abundant elements on Earth, and in its pure form the material has become the foundation of much of modern technology, from solar cells to computer chips. But silicon’s properties as a semiconductor are far from ideal. For one thing, although silicon lets electrons whizz through its structure easily, it is much less accommodating to “holes” — electrons’ positively charged counterparts — and harnessing both is important for some kinds of chips. What’s more, silicon is not very good at conducting heat, which is why…