Due to its polar nature, these reagennts were soluble enough in THF to facilitate charge Therefore for injecting holes and thereby oxidising, Cu 3-x P nanocrystals were treated with ceric ammonium nitrate (CAN). As a result of the redox reaction, the Ce 4+ ions in CAN will be reduced to Ce 3+ . This resulted in blueshift and subsequent increase in the extinction. Similarly, to provide a reducing environment, lithium triethylborohydride (LTBH) was added to a fresh solution of Cu 3-x P. A redshift was observed following its addition. These were in agreement with the spectroelectrochemical studies and the treatment with LiPF 6 .