Lego Batman Strategy Guide 67: The Face-Off, Free Play
There will really be nothing to do here until you get to the bank entrance. To the left of the entrance will be a panel that can be used by Techno Suit Robin to shut off the lasers on the front of the bank. Now you can approach the entrance without getting shot at. You can then go to the rotating door and get the Sixth Canister.
In one corner is the Attracto machine, which you can actually use now. There should be more than 25 green, red, and yellow things to suck up, so go ahead and use it. The sprinklers will start up, and you can bounce on top of the plants that it grows until there is one that acts as a trampoline. Go ahead and go to the right where there is a ledge on the right. Jump up as a high jumper to one level, where there is Hostage 11/25. The Seventh Canister is also here.
There should be enough to fill up your Attracto pack with another 25 items. Go ahead and do that, and you should be able to go back to the Attracto machine area and it will literally plant several blue studs.
Now, go to the area where the toxic waste is. You will notice after you face Two-Face the first time, that there is some stuff you can do. For example, before you cross the three platforms, you should go left. There is an open pipe to the left that has the Eighth Canister inside.
As you cross the three platforms, become a toxic resistant character and just step down into this pit. The Ninth Canister is right there, and is quite easy to miss.
You can fill that after bashing in some stuff, you will find in some holes with some colored circular Lego pieces, and then jump on whatever color light is on the vault door. You need to step on the red first, and allow the vault door to screw open until the light turns green. Do the same for the blue, the green, and the purple spots. The Power Brick is beyond that door.
There is another area on the right. If you use the Mr. Freeze, he can freeze some water that is coming out. This will create and icy ledge, and you should become Poison Ivy. (You should preferably get on solid ground and turn into her, or you could end up falling into toxic waste.) Jump up and get the Tenth Canister.