You mean like welding the panels together using glass? Since you'd need to heat the panels up to accept the glass 'welding rod', I don't know if you could do it without causing a lot of heat generated ripples/distortion near the seams...or break the glass altogether
This is not a task that can be accomplished without proper equipment, even then, it is a rather difficult process. A professional glass worker would probably go about it another way all together. In short, you fuse glass, not weld it. I could go further but I doubt you all would find it interesting or the least bit relevant.
If it is the silicone that you don't want and you are planning to make a small tank, you might want to try an adhesive called UV glue. It is an adhesive that sets up under UV light, pretty cool stuff! the finished result looks really nice, alot like those Azoo Palm aquariums. The issues with this adhesive is that your glass needs to be cut perfect as this glue does not fill gaps.I also do not know how strong thhe bond is in regards to making a large tank with a lot of water pressure. I have made small tanks with this stuff ( approx. 7 gal)