Thin film technology – the application of materials ranging between several micrometers and a fraction of a nanometer in thickness – is increasingly becoming a major focus of scientific and technological approaches to tackling climate change. A number of green thin film technologies are in use today or are being developed, from successful experiments with thin film biofilters to the growing use of thin film battery technology, and now to the mainstream application of thin film photovoltaics.

In recent years, black phosphorus (BP or phosphorene), a novel two-dimensional (2D) semiconducting material, has gained tremendous attention because of its intriguing properties, such as ON/OFF ratio, high carrier mobility, and tunable direct band.