Chemically bonded amorphous red phosphorous with disordered carbon nanosheet as high voltage cathode for rechargeable aluminium ion battery

Development of high specific capacity cathode operating at higher voltage can lead to the development of rechargeable aluminium ion battery as a promising energy storage device for large scale application. Herein we have designed a cathode structure with red phosphorous nanoparticles embedded in disordered carbon nanosheets (Red P@DCNS) from a cost-effective resource by a simple and scalable technique. The combined interaction of red phosphorous and DCNS with aluminium ions enables to achieve a specific capacity of 350 mAh g⁻¹ at 30 mA g⁻¹ with a high operating voltage of 1.95 V. Moreover, the smaller size and strong chemical bonding of red phosphorous to DCNS facilitates for the stable capacity over 500 cycles with a coulombic efficiency of nearly 100%. Interestingly, it is inferred from the post-analysis study that trivalent aluminium ions react reversibly with red phosphorous and oxygen present in DCNS to form aluminium phosphate which is responsible for high specific capacity. Red P@DCNS possess both high discharge voltage of 1.95 V and higher specific capacity surpassing the aluminium ion batteries previously reported. These findings are of great significant and provide a new concept of designing a high voltage cathode and can lead to further advancement towards the development of rechargeable aluminium ion battery.