Most of the tutorials for Photon and NFC I found uses SPI and RC522 Modules. Since I am a big fan of the grove system, I tried to connect the Grove NFC with my photon to read out the UID of a NFC card.
You need to change the Grove NFC module a little bit so that it works with I2C because the default mode of the module is UART.
Some features will not work with I2C because of limitations of Wire framework https://community.particle.io/t/photon-i2c-nfc-ndef/14109. You will need UART or SPI for those features (e.g: emulation tag)
A great discussion thread about PN522 NFC Lib can be found here: https://community.particle.io/t/pn532-nfc-library-ported/2675/117