Page 12 - PERIODIC 2017
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              refused to gain any financial reward from his burner and  qweqwertyuiop[asdfghjkl;zxcvbnm,.QWERTYUI
                                                                – few cared then about the environment but they did care
              there was even a Bunsen battery that belched out NO . The   about finding alternatives for oil.  Stan cleverly combined this
                                                        X
              Bunsen philosophy still pervaded most of the department.   with his earlier work and in summer 1976 announced a room
              Whenever Peter was asked about his interests he would   temperature, rechargeable lithium titanium disulfide battery.
              always reply, “Oh, they’re as pure as the driven snow.’’   This battery had a respectable 2 volts plus and with lithium
                                                                being light, small and electropositive had a good energy and
              I was very briefly under the wing of Rod Hurditch who,
              on paper, was doing a Post Doc with JS. I was told that if Rod   current density. Room temperature allowed a liquid, non-
              had been active at the weekend, you could come in on a   aqueous electrolyte to be used;   discharge and recharge
              Monday morning and not recognise the place. These were   involved a fast, non-disruptive intercalation/de-intercalation
              pioneering days in the lab both for solid state chemistry and   of the cathode (0 ≤ x ≤1):
              powder diffraction. JS had brought in Brian Fender with his   discharge   g   xLi+TiS    =   Li TiS     charge
                                                                                             2 f
                                                                                          x
                                                                                   2

              stable of St Catz thoroughbreds, most notably Allan Jacobson
              and Bruce Tofield. Years later, I overheard Prof Malcolm   Despite it providing the foundation for later developments,
              Green correctly inform a visitor that, “This department has   the battery would be abandoned before the end of the
              filled the world with solid state chemists.”         decade. Later, when Allan Jacobson, now at Exxon, visited
                                                                the lab, he said to me, “You won’t do it with lithium.” On
              Our main competitor in the bronze field was Hagenmuller’s   recycling, dendrites grew on the lithium anode and internally
              Bordeaux group who were exhaustively exploring high   short-circuited the cell.
              temperature syntheses in sealed gold tubes. Peter Larkham
              was dispatched there for training.  Apparently, tea came
              round on spotless trolleys; using a glove box while stood on a  Fugue
              pile of Dexion wasn’t a common sight either.
                                                                So this was the situation when John Goodenough arrived
              A hidden facet of solid state chemistry was gradually being   in September 1976. The first thing he ever said to me was
              exposed – new, often metastable, solids could be made at   that he was ‘riding loose’, a phrase I’ve never heard here
              low temperature by kinetic control, partial ionic mobility   before or since. I was also exposed to the Goodenough
              permitting. That significant electron and proton mobility in   laugh, the decibels of which were out of all proportion to
              H WO , coupled to its colour changes, found application in   the quality of joke that induced it. With no qualifications
               X   3
              electrochromic display devices we noted only in passing;   in chemistry, perhaps an unusual choice for Professor, but
              possibly, the MnO  ‘depolariser’ in the Leclanché cell might   his recent work at MIT designing new solid electrolytes
                            2
                                   +
              be  H MnO  . While the Na  ions in cubic Na WO   were   was sure to get funding. When Peter learnt of John’s grant
                  X    2                        X   3
              imprisoned in their perovskite cells, an oddball electrical   success, he quipped, “I’ll give you four years before you’re
              insulator called sodium beta-alumina was found in 1967  to   rumbled.” The ‘JBG group’ occupied a room adjoining the
              have a Na  ion mobility similar to that of a liquid, the first of   Abbots Kitchen which John called ‘the rats nest’ and avoided
                     +
              the ‘superionic conductors’. This found use as the electrolyte   at all costs. Instead, ‘strategy sessions’ took place at his
              in the rechargeable sodium sulfur battery operating around   blackboard where you took great care not to tread chalk into
              350C and also hampered by aggressive electrodes and slow   the Professorial carpet. During one of these, I queried what
              secondary phase formation:                        would happen if you took a known lithiated oxide, LiMO ,
                                                                                                            n
                                                                and then tried to extract lithium electrochemically. How
              2Na + xS   =   Na S
                            2 x                                 many lithium props could you remove before the oxide roof
              Stan wanted to make Na  ionic                     caved in? This was an inversion of the Whittingham theme –
                                 +
              conductivity measurements                         a new metastable phase would
              on beta-alumina and, with                         now be produced in the charge
              his Oxford training, tried                        rather than the discharge cycle.
              Na WO  electrodes choosing
                X
                    3
              the structure opposite with                       Bill England, a former Part II of
              larger channels. He found the                     Allan’s, was investigating low
              electrodes reversible to Na .                     temperature ion-exchange, a
                                   +
              Despite the tiny current, it                      footprint of potential fast-ion
              was another indication that bronzes might play a role in the   conductors. Surprisingly, even
              battery scene.                                    spinel phases exchanged and
                                                                later they’d be used as cathode
              Stan moved to the mighty Exxon Corporation in New Jersey   materials. Crucially, so did
              where researchers were working on the superconducting   LiCrO , an ordered rock salt
                                                                     2
              properties of lithiated layered transition metal sulfides   structure whose layers emerge -
              synthesised at room temperature using nBuLi.  We’re now   when you looked down the body
              in the energy crisis of the early 70s with rocketing oil prices   diagonal of the cube.




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              Periodic       The Magazine of the Department of Chemistry
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