QC fast charging and PD fast charging are two different fast charging protocols. The biggest difference between the two is that they support the maximum charging power.
The range of dynamic current and voltage adjustment and the compatibility of different devices are different.
PD fast charge is better than QC fast charge in these aspects, and the difference may not be obvious for mobile phone batteries.
Because the mobile phone hardware limits the maximum charging power, QC fast charging may be more suitable for mobile phone charging.
Android phone using Qualcomm QC3.0 is basically all applicable. As for the charging speed? Compared with the original charger, like Huawei mobile phones, the original can basically reach 22w. But with a QC3.0 charger, the charging speed is about between 15-20W. The effect is still discounted. Considering the high cost of the original charger, this QC3.0 charger is still the best choice for fast charging of Android phones.
Old version of iPhones including iPhone 7 and the former ones can reach 8 or 9w if using the QC3.0 charger, still faster than the original Apple charger.
New Apple mobile phones above iPhone 8 support fast charging, PD fast charging. But with a condition, you must have an original Apple or Apple authorized USB-C to lightning data cable.
Let's talk about this PD fast charge. PD can be said to be an all-around fast charge. In addition to the fast charging function for Apple mobile phones, it is also compatible with all mainstream fast charging protocols on the market such as QC3.0, Huawei, Samsung. It is output through the USB-C port. The biggest difference between USB-C and the USB-A port used by most chargers is that it supports high current. So basically, as long as the PD is used, most mobile phones charge super fast, and can basically reach the highest current that the mobile phone system can recognize. For example, if you don't have an Apple adapter cable, you can achieve 10W with PD charging.
In the future, PD will be the mainstream of fast charging, and transfer data cables supporting USB-C will gradually become popular.